A\x20go.mod\x0afile,\x20together\x20with\x20information\x20about\x20the\x20module's\x0adependencies.\x20The\x20go.mod\x20file.\x20The\x20go\x20command\x20is\x20invoked.
Each\x20"golang.org/x/net"\x20contains\x20a\x20package\x20in\x20the\x20directory\x20"html".\x20That\x0apackage's\x20path\x20is\x20"golang.org/x/net/html".
A\x20module\x20directive\x20in\x20the\x20module's\x0ago.mod\x20file.\x20A\x20module's\x20path\x20is\x20the\x20prefix\x20for\x20package\x0apaths\x20within\x20the\x20module.
A\x20module\x20path\x20should\x20describe\x20both\x20what\x20the\x20module\x20does\x20and\x20where\x20to\x20find\x20it.\x0aTypically,\x20a\x20module\x20path\x20consists\x20of\x20a\x20repository\x20root\x20path,\x20a\x20directory\x20within\x0athe\x20repository\x20(usually\x20empty),\x20and\x20a\x20major\x20version\x20suffix\x20(only\x20for\x20major\x0aversion\x202\x20or\x20higher).
\x0agolang.org/x/net\x20is\x20the\x20repository\x20root\x20path\x20for\x20the\x20module\x20of\x20the\x20same\x0aname.\x20See\x20go\x20command\x20locates\x20a\x20repository\x20using\x20HTTP\x20requests\x20derived\x0afrom\x20a\x20module\x20path.golang.org/x/tools/gopls\x20is\x20in\x20the\x20gopls\x20subdirectory\x20of\x20the\x20repository\x0awith\x20root\x20path\x20golang.org/x/tools,\x20so\x20it\x20has\x20the\x20module\x20subdirectory\x0agopls.\x20See\x20/v2.\x20This\x20may\x20or\x20may\x20not\x20be\x20part\x20of\x20the\x20subdirectory\x20name.\x20For\x20example,\x20the\x0amodule\x20with\x20path\x20golang.org/x/repo/sub/v2\x20could\x20be\x20in\x20the\x20/sub\x20or\x0a/sub/v2\x20subdirectory\x20of\x20the\x20repository\x20golang.org/x/repo.If\x20a\x20module\x20might\x20be\x20depended\x20on\x20by\x20other\x20modules,\x20these\x20rules\x20must\x20be\x20followed\x0aso\x20that\x20the\x20go\x20command\x20can\x20find\x20and\x20download\x20the\x20module.\x20There\x20are\x20also\x0aseveral\x20
A\x20v,\x20followed\x20by\x20a\x20semantic\x20version.\x20See\x20
To\x20summarize,\x20a\x20semantic\x20version\x20consists\x20of\x20three\x20non-negative\x20integers\x20(the\x0amajor,\x20minor,\x20and\x20patch\x20versions,\x20from\x20left\x20to\x20right)\x20separated\x20by\x20dots.\x20The\x0apatch\x20version\x20may\x20be\x20followed\x20by\x20an\x20optional\x20pre-release\x20string\x20starting\x20with\x20a\x0ahyphen.\x20The\x20pre-release\x20string\x20or\x20patch\x20version\x20may\x20be\x20followed\x20by\x20a\x20build\x0ametadata\x20string\x20starting\x20with\x20a\x20plus.\x20For\x20example,\x20v0.0.0,\x20v1.12.134,\x0av8.0.5-pre,\x20and\x20v2.0.9+meta\x20are\x20valid\x20versions.
Each\x20part\x20of\x20a\x20version\x20indicates\x20whether\x20the\x20version\x20is\x20stable\x20and\x20whether\x20it\x20is\x0acompatible\x20with\x20previous\x20versions.
\x0av1.2.3-pre\x20comes\x20before\x0av1.2.3.go.mod\x20files.\x20The\x0asuffix\x20+incompatible\x20denotes\x20a\x20version\x20released\x20before\x20migrating\x20to\x20modules\x0aversion\x20major\x20version\x202\x20or\x20later\x20(see\x20A\x20version\x20is\x20considered\x20unstable\x20if\x20its\x20major\x20version\x20is\x200\x20or\x20it\x20has\x20a\x0apre-release\x20suffix.\x20Unstable\x20versions\x20are\x20not\x20subject\x20to\x20compatibility\x0arequirements.\x20For\x20example,\x20v0.2.0\x20may\x20not\x20be\x20compatible\x20with\x20v0.1.0,\x20and\x0av1.5.0-beta\x20may\x20not\x20be\x20compatible\x20with\x20v1.5.0.
Go\x20may\x20access\x20modules\x20in\x20version\x20control\x20systems\x20using\x20tags,\x20branches,\x20or\x0arevisions\x20that\x20don't\x20follow\x20these\x20conventions.\x20However,\x20within\x20the\x20main\x20module,\x0athe\x20go\x20command\x20will\x20automatically\x20convert\x20revision\x20names\x20that\x20don't\x20follow\x0athis\x20standard\x20into\x20canonical\x20versions.\x20The\x20go\x20command\x20will\x20also\x20remove\x20build\x0ametadata\x20suffixes\x20(except\x20for\x20+incompatible)\x20as\x20part\x20of\x20this\x20process.\x20This\x20may\x0aresult\x20in\x20a\x20go\x20get\x20-d\x20golang.org/x/net@daa7c041\x20will\x20convert\x20the\x20commit\x20hash\x20daa7c041\x20into\x20the\x0apseudo-version\x20v0.0.0-20191109021931-daa7c04131f5.\x20Canonical\x20versions\x20are\x0arequired\x20outside\x20the\x20main\x20module,\x20and\x20the\x20go\x20command\x20will\x20report\x20an\x20error\x20if\x20a\x0anon-canonical\x20version\x20like\x20master\x20appears\x20in\x20a\x20go.mod\x20file.
A\x20pseudo-version\x20is\x20a\x20specially\x20formatted\x0av0.0.0-20191109021931-daa7c04131f5\x20is\x20a\x20pseudo-version.
Pseudo-versions\x20may\x20refer\x20to\x20revisions\x20for\x20which\x20no\x20
Each\x20pseudo-version\x20has\x20three\x20parts:
\x0avX.0.0\x20or\x20vX.Y.Z-0),\x20which\x20is\x20either\x20derived\x20from\x20a\x0asemantic\x20version\x20tag\x20that\x20precedes\x20the\x20revision\x20or\x20vX.0.0\x20if\x20there\x20is\x20no\x0asuch\x20tag.yymmddhhmmss),\x20which\x20is\x20the\x20UTC\x20time\x20the\x20revision\x20was\x20created.\x0aIn\x20Git,\x20this\x20is\x20the\x20commit\x20time,\x20not\x20the\x20author\x20time.abcdefabcdef),\x20which\x20is\x20a\x2012-character\x20prefix\x20of\x20the\x0acommit\x20hash,\x20or\x20in\x20Subversion,\x20a\x20zero-padded\x20revision\x20number.Each\x20pseudo-version\x20may\x20be\x20in\x20one\x20of\x20three\x20forms,\x20depending\x20on\x20the\x20base\x20version.\x0aThese\x20forms\x20ensure\x20that\x20a\x20pseudo-version\x20compares\x20higher\x20than\x20its\x20base\x20version,\x0abut\x20lower\x20than\x20the\x20next\x20tagged\x20version.
\x0avX.0.0-yyyymmddhhmmss-abcdefabcdef\x20is\x20used\x20when\x20there\x20is\x20no\x20known\x20base\x0aversion.\x20As\x20with\x20all\x20versions,\x20the\x20major\x20version\x20X\x20must\x20match\x20the\x20module's\x0avX.Y.Z-pre.0.yyyymmddhhmmss-abcdefabcdef\x20is\x20used\x20when\x20the\x20base\x20version\x20is\x0aa\x20pre-release\x20version\x20like\x20vX.Y.Z-pre.vX.Y.(Z+1)-0.yyyymmddhhmmss-abcdefabcdef\x20is\x20used\x20when\x20the\x20base\x20version\x20is\x0aa\x20release\x20version\x20like\x20vX.Y.Z.\x20For\x20example,\x20if\x20the\x20base\x20version\x20is\x0av1.2.3,\x20a\x20pseudo-version\x20might\x20be\x20v1.2.4-0.20191109021931-daa7c04131f5.More\x20than\x20one\x20pseudo-version\x20may\x20refer\x20to\x20the\x20same\x20commit\x20by\x20using\x20different\x0abase\x20versions.\x20This\x20happens\x20naturally\x20when\x20a\x20lower\x20version\x20is\x20tagged\x20after\x20a\x0apseudo-version\x20is\x20written.
\x0aThese\x20forms\x20give\x20pseudo-versions\x20two\x20useful\x20properties:
\x0aThe\x20go\x20command\x20performs\x20several\x20checks\x20to\x20ensure\x20that\x20module\x20authors\x20have\x0acontrol\x20over\x20how\x20pseudo-versions\x20are\x20compared\x20with\x20other\x20versions\x20and\x20that\x0apseudo-versions\x20refer\x20to\x20revisions\x20that\x20are\x20actually\x20part\x20of\x20a\x20module's\x0acommit\x20history.
v1.999.999-99999999999999-daa7c04131f5.Pseudo-versions\x20never\x20need\x20to\x20be\x20typed\x20by\x20hand.\x20Many\x20commands\x20accept\x0aa\x20commit\x20hash\x20or\x20a\x20branch\x20name\x20and\x20will\x20translate\x20it\x20into\x20a\x20pseudo-version\x0a(or\x20tagged\x20version\x20if\x20available)\x20automatically.\x20For\x20example:
\x0ago\x20get\x20-d\x20example.com/mod@master\x0ago\x20list\x20-m\x20-json\x20example.com/mod@abcd1234\x0aStarting\x20with\x20major\x20version\x202,\x20module\x20paths\x20must\x20have\x20a\x20/v2\x20that\x20matches\x20the\x20major\x0aversion.\x20For\x20example,\x20if\x20a\x20module\x20has\x20the\x20path\x20example.com/mod\x20at\x20v1.0.0,\x20it\x0amust\x20have\x20the\x20path\x20example.com/mod/v2\x20at\x20version\x20v2.0.0.
Major\x20version\x20suffixes\x20implement\x20the\x20
\x0a\x0aIf\x20an\x20old\x20package\x20and\x20a\x20new\x20package\x20have\x20the\x20same\x20import\x20path,\x0athe\x20new\x20package\x20must\x20be\x20backwards\x20compatible\x20with\x20the\x20old\x20package.
\x0a
By\x20definition,\x20packages\x20in\x20a\x20new\x20major\x20version\x20of\x20a\x20module\x20are\x20not\x20backwards\x0acompatible\x20with\x20the\x20corresponding\x20packages\x20in\x20the\x20previous\x20major\x20version.\x0aConsequently,\x20starting\x20with\x20v2,\x20packages\x20need\x20new\x20import\x20paths.\x20This\x20is\x0aaccomplished\x20by\x20adding\x20a\x20major\x20version\x20suffix\x20to\x20the\x20module\x20path.\x20Since\x20the\x0amodule\x20path\x20is\x20a\x20prefix\x20of\x20the\x20import\x20path\x20for\x20each\x20package\x20within\x20the\x20module,\x0aadding\x20the\x20major\x20version\x20suffix\x20to\x20the\x20module\x20path\x20provides\x20a\x20distinct\x20import\x0apath\x20for\x20each\x20incompatible\x20version.
Major\x20version\x20suffixes\x20are\x20not\x20allowed\x20at\x20major\x20versions\x20v0\x20or\x20v1.\x20There\x20is\x0ano\x20need\x20to\x20change\x20the\x20module\x20path\x20between\x20v0\x20and\x20v1\x20because\x20v0\x20versions\x0aare\x20unstable\x20and\x20have\x20no\x20compatibility\x20guarantee.\x20Additionally,\x20for\x20most\x0amodules,\x20v1\x20is\x20backwards\x20compatible\x20with\x20the\x20last\x20v0\x20version;\x20a\x20v1\x20version\x0aacts\x20as\x20a\x20commitment\x20to\x20compatibility,\x20rather\x20than\x20an\x20indication\x20of\x0aincompatible\x20changes\x20compared\x20with\x20v0.
As\x20a\x20special\x20case,\x20modules\x20paths\x20starting\x20with\x20gopkg.in/\x20must\x20always\x20have\x20a\x0amajor\x20version\x20suffix,\x20even\x20at\x20v0\x20and\x20v1.\x20The\x20suffix\x20must\x20start\x20with\x20a\x20dot\x0arather\x20than\x20a\x20slash\x20(for\x20example,\x20gopkg.in/yaml.v2).
Major\x20version\x20suffixes\x20let\x20multiple\x20major\x20versions\x20of\x20a\x20module\x20coexist\x20in\x20the\x0asame\x20build.\x20This\x20may\x20be\x20necessary\x20due\x20to\x20a\x20
Many\x20Go\x20projects\x20released\x20versions\x20at\x20v2\x20or\x20higher\x20without\x20using\x20a\x20major\x0aversion\x20suffix\x20before\x20migrating\x20to\x20modules\x20(perhaps\x20before\x20modules\x20were\x20even\x0aintroduced).\x20These\x20versions\x20are\x20annotated\x20with\x20a\x20+incompatible\x20build\x20tag\x20(for\x0aexample,\x20v2.0.0+incompatible).\x20See\x20
When\x20the\x20go\x20command\x20loads\x20a\x20package\x20using\x20a\x20
The\x20go\x20command\x20starts\x20by\x20searching\x20the\x20example.com/a/b\x20is\x20imported,\x20and\x20the\x20module\x20example.com/a\x20is\x20in\x20the\x0abuild\x20list,\x20the\x20go\x20command\x20will\x20check\x20whether\x20example.com/a\x20contains\x20the\x0apackage,\x20in\x20the\x20directory\x20b.\x20At\x20least\x20one\x20file\x20with\x20the\x20.go\x20extension\x20must\x0abe\x20present\x20in\x20a\x20directory\x20for\x20it\x20to\x20be\x20considered\x20a\x20package.\x20go\x20command\x20will\x20attempt\x20to\x0afind\x20a\x20new\x20module\x20(unless\x20the\x20flags\x20-mod=readonly\x20or\x20-mod=vendor\x20are\x20used,\x0ain\x20which\x20case,\x20an\x20error\x20is\x20reported).
When\x20the\x20go\x20command\x20looks\x20up\x20a\x20new\x20module\x20for\x20a\x20package\x20path,\x20it\x20checks\x20the\x0aGOPROXY\x20environment\x20variable,\x20which\x20is\x20a\x20comma-separated\x20list\x20of\x20proxy\x20URLs\x20or\x0athe\x20keywords\x20direct\x20or\x20off.\x20A\x20proxy\x20URL\x20indicates\x20the\x20go\x20command\x20should\x0acontact\x20a\x20GOPROXY\x0aprotocol.\x20direct\x20indicates\x20that\x20the\x20go\x20command\x20should\x0aoff\x20indicates\x20that\x20no\x0acommunication\x20should\x20be\x20attempted.\x20The\x20GOPRIVATE\x20and\x20GONOPROXY\x20
For\x20each\x20entry\x20in\x20the\x20GOPROXY\x20list,\x20the\x20go\x20command\x20requests\x20the\x20latest\x0aversion\x20of\x20each\x20module\x20path\x20that\x20might\x20provide\x20the\x20package\x20(that\x20is,\x20each\x20prefix\x0aof\x20the\x20package\x20path).\x20For\x20each\x20successfully\x20requested\x20module\x20path,\x20the\x20go\x0acommand\x20will\x20download\x20the\x20module\x20at\x20the\x20latest\x20version\x20and\x20check\x20whether\x20the\x0amodule\x20contains\x20the\x20requested\x20package.\x20If\x20one\x20or\x20more\x20modules\x20contain\x20the\x0arequested\x20package,\x20the\x20module\x20with\x20the\x20longest\x20path\x20is\x20used.\x20If\x20one\x20or\x20more\x0amodules\x20are\x20found\x20but\x20none\x20contain\x20the\x20requested\x20package,\x20an\x20error\x20is\x0areported.\x20If\x20no\x20modules\x20are\x20found,\x20the\x20go\x20command\x20tries\x20the\x20next\x20entry\x20in\x20the\x0aGOPROXY\x20list.\x20If\x20no\x20entries\x20are\x20left,\x20an\x20error\x20is\x20reported.
For\x20example,\x20suppose\x20the\x20go\x20command\x20is\x20looking\x20for\x20a\x20module\x20that\x20provides\x20the\x0apackage\x20golang.org/x/net/html,\x20and\x20GOPROXY\x20is\x20set\x20to\x0ahttps://corp.example.com,https://proxy.golang.org.\x20The\x20go\x20command\x20may\x20make\x0athe\x20following\x20requests:
https://corp.example.com/\x20(in\x20parallel):\x0agolang.org/x/net/htmlgolang.org/x/netgolang.org/xgolang.orghttps://proxy.golang.org/,\x20if\x20all\x20requests\x20to\x20https://corp.example.com/\x0ahave\x20failed\x20with\x20404\x20or\x20410:\x0agolang.org/x/net/htmlgolang.org/x/netgolang.org/xgolang.orgAfter\x20a\x20suitable\x20module\x20has\x20been\x20found,\x20the\x20go\x20command\x20will\x20add\x20a\x20new\x0ago.mod\x20file.\x20This\x20ensures\x20that\x20when\x20the\x20same\x20package\x20is\x20loaded\x0ain\x20the\x20future,\x20the\x20same\x20module\x20will\x20be\x20used\x20at\x20the\x20same\x20version.\x20If\x20the\x20resolved\x0apackage\x20is\x20not\x20imported\x20by\x20a\x20package\x20in\x20the\x20main\x20module,\x20the\x20new\x20requirement\x0awill\x20have\x20an\x20//\x20indirect\x20comment.
go.mod\x20filesA\x20module\x20is\x20defined\x20by\x20a\x20UTF-8\x20encoded\x20text\x20file\x20named\x20go.mod\x20in\x20its\x20root\x0adirectory.\x20The\x20go.mod\x20file\x20is\x20line-oriented.\x20Each\x20line\x20holds\x20a\x20single\x0adirective,\x20made\x20up\x20of\x20a\x20keyword\x20followed\x20by\x20arguments.\x20For\x20example:
module\x20example.com/my/thing\x0a\x0ago\x201.12\x0a\x0arequire\x20example.com/other/thing\x20v1.0.2\x0arequire\x20example.com/new/thing/v2\x20v2.3.4\x0aexclude\x20example.com/old/thing\x20v1.2.3\x0areplace\x20example.com/bad/thing\x20v1.4.5\x20=>\x20example.com/good/thing\x20v1.4.5\x0aThe\x20leading\x20keyword\x20can\x20be\x20factored\x20out\x20of\x20adjacent\x20lines\x20to\x20create\x20a\x20block,\x0alike\x20in\x20Go\x20imports.
\x0arequire\x20(\x0a\x20\x20\x20\x20example.com/new/thing/v2\x20v2.3.4\x0a\x20\x20\x20\x20example.com/old/thing\x20v1.2.3\x0a)\x0aThe\x20go.mod\x20file\x20is\x20designed\x20to\x20be\x20human\x20readable\x20and\x20machine\x20writable.\x20The\x0ago\x20command\x20provides\x20several\x20subcommands\x20that\x20change\x20go.mod\x20files.\x20For\x0aexample,\x20go\x20get\x20can\x20upgrade\x20or\x20downgrade\x20specific\x20dependencies.\x0aCommands\x20that\x20load\x20the\x20module\x20graph\x20will\x20go.mod\x20when\x20needed.\x20go\x20mod\x20edit\x20can\x20perform\x20low-level\x20edits.\x0aThe\x0agolang.org/x/mod/modfile\x0apackage\x20can\x20be\x20used\x20by\x20Go\x20programs\x20to\x20make\x20the\x20same\x20changes\x20programmatically.
When\x20a\x20go.mod\x20file\x20is\x20parsed,\x20its\x20content\x20is\x20broken\x20into\x20a\x20sequence\x20of\x20tokens.\x0aThere\x20are\x20several\x20kinds\x20of\x20tokens:\x20whitespace,\x20comments,\x20punctuation,\x0akeywords,\x20identifiers,\x20and\x20strings.
White\x20space\x20consists\x20of\x20spaces\x20(U+0020),\x20tabs\x20(U+0009),\x20carriage\x20returns\x0a(U+000D),\x20and\x20newlines\x20(U+000A).\x20White\x20space\x20characters\x20other\x20than\x20newlines\x20have\x0ano\x20effect\x20except\x20to\x20separate\x20tokens\x20that\x20would\x20otherwise\x20be\x20combined.\x20Newlines\x0aare\x20significant\x20tokens.
\x0aComments\x20start\x20with\x20//\x20and\x20run\x20to\x20the\x20end\x20of\x20a\x20line.\x20/*\x20*/\x20comments\x20are\x0anot\x20allowed.
Punctuation\x20tokens\x20include\x20(,\x20),\x20and\x20=>.
Keywords\x20distinguish\x20different\x20kinds\x20of\x20directives\x20in\x20a\x20go.mod\x20file.\x20Allowed\x0akeywords\x20are\x20module,\x20go,\x20require,\x20replace,\x20and\x20exclude.
Identifiers\x20are\x20sequences\x20of\x20non-whitespace\x20characters,\x20such\x20as\x20module\x20paths\x0aor\x20semantic\x20versions.
\x0aStrings\x20are\x20quoted\x20sequences\x20of\x20characters.\x20There\x20are\x20two\x20kinds\x20of\x20strings:\x0ainterpreted\x20strings\x20beginning\x20and\x20ending\x20with\x20quotation\x20marks\x20(",\x20U+0022)\x20and\x0araw\x20strings\x20beginning\x20and\x20ending\x20with\x20grave\x20accents\x20(<,\x0aU+0060).\x20Interpreted\x20strings\x20may\x20contain\x20escape\x20sequences\x20consisting\x20of\x20a\x0abackslash\x20(\\,\x20U+005C)\x20followed\x20by\x20another\x20character.\x20An\x20escaped\x20quotation\x0amark\x20(\\")\x20does\x20not\x20terminate\x20an\x20interpreted\x20string.\x20The\x20unquoted\x20value\x0aof\x20an\x20interpreted\x20string\x20is\x20the\x20sequence\x20of\x20characters\x20between\x20quotation\x0amarks\x20with\x20each\x20escape\x20sequence\x20replaced\x20by\x20the\x20character\x20following\x20the\x0abackslash\x20(for\x20example,\x20\\"\x20is\x20replaced\x20by\x20",\x20\\n\x20is\x20replaced\x20by\x20n).\x0aIn\x20contrast,\x20the\x20unquoted\x20value\x20of\x20a\x20raw\x20string\x20is\x20simply\x20the\x20sequence\x20of\x0acharacters\x20between\x20grave\x20accents;\x20backslashes\x20have\x20no\x20special\x20meaning\x20within\x0araw\x20strings.
Identifiers\x20and\x20strings\x20are\x20interchangeable\x20in\x20the\x20go.mod\x20grammar.
Most\x20identifiers\x20and\x20strings\x20in\x20a\x20go.mod\x20file\x20are\x20either\x20module\x20paths\x20or\x0aversions.
A\x20module\x20path\x20must\x20satisfy\x20the\x20following\x20requirements:
\x0a/,\x20U+002F).\x20It\x20must\x20not\x20begin\x20or\x20end\x20with\x20a\x20slash.+,\x20-,\x20.,\x20_,\x20and\x20~)..,\x20U+002E).CON,\x20com1,\x20NuL,\x20and\x20so\x20on).If\x20the\x20module\x20path\x20appears\x20in\x20a\x20require\x20directive\x20and\x20is\x20not\x20replaced,\x20or\x0aif\x20the\x20module\x20paths\x20appears\x20on\x20the\x20right\x20side\x20of\x20a\x20replace\x20directive,\x0athe\x20go\x20command\x20may\x20need\x20to\x20download\x20modules\x20with\x20that\x20path,\x20and\x20some\x0aadditional\x20requirements\x20must\x20be\x20satisfied.
.,\x20U+002E),\x20and\x20dashes\x20(-,\x20U+002D);\x20it\x20must\x20contain\x20at\x20least\x20one\x20dot\x20and\x0acannot\x20start\x20with\x20a\x20dash./vN\x20where\x20N\x20looks\x20numeric\x20(ASCII\x0adigits\x20and\x20dots),\x20N\x20must\x20not\x20begin\x20with\x20a\x20leading\x20zero,\x20must\x20not\x20be\x20/v1,\x0aand\x20must\x20not\x20contain\x20any\x20dots.\x0agopkg.in/,\x20this\x20requirement\x20is\x20replaced\x20by\x20a\x0arequirement\x20that\x20the\x20path\x20follow\x20the\x20Versions\x20in\x20go.mod\x20files\x20may\x20be\x20
A\x20canonical\x20version\x20starts\x20with\x20the\x20letter\x20v,\x20followed\x20by\x20a\x20semantic\x20version\x0afollowing\x20the\x20
Most\x20other\x20identifiers\x20and\x20strings\x20may\x20be\x20used\x20as\x20non-canonical\x20versions,\x20though\x0athere\x20are\x20some\x20restrictions\x20to\x20avoid\x20problems\x20with\x20file\x20systems,\x20repositories,\x0aand\x20go.mod\x20file.\x20The\x20go\x20command\x20will\x20attempt\x20to\x0areplace\x20each\x20non-canonical\x20version\x20with\x20an\x20equivalent\x20canonical\x20version\x20when\x20it\x0aautomatically\x20go.mod\x20file.
In\x20places\x20where\x20a\x20module\x20path\x20is\x20associated\x20with\x20a\x20verison\x20(as\x20in\x20require,\x0areplace,\x20and\x20exclude\x20directives),\x20the\x20final\x20path\x20element\x20must\x20be\x20consistent\x0awith\x20the\x20version.\x20See\x20
go.mod\x20syntax\x20is\x20specified\x20below\x20using\x20Extended\x20Backus-Naur\x20Form\x20(EBNF).\x0aSee\x20the\x20
GoMod\x20=\x20{\x20Directive\x20}\x20.\x0aDirective\x20=\x20ModuleDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GoDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20RequireDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20ExcludeDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20ReplaceDirective\x20.\x0aNewlines,\x20identifiers,\x20and\x20strings\x20are\x20denoted\x20with\x20newline,\x20ident,\x20and\x0astring,\x20respectively.
Module\x20paths\x20and\x20versions\x20are\x20denoted\x20with\x20ModulePath\x20and\x20Version.
ModulePath\x20=\x20ident\x20|\x20string\x20.\x20/*\x20see\x20restrictions\x20above\x20*/\x0aVersion\x20=\x20ident\x20|\x20string\x20.\x20\x20\x20\x20/*\x20see\x20restrictions\x20above\x20*/\x0amodule\x20directiveA\x20module\x20directive\x20defines\x20the\x20main\x20module's\x20go.mod\x20file\x20must\x20contain\x20exactly\x20one\x20module\x20directive.
ModuleDirective\x20=\x20"module"\x20(\x20ModulePath\x20|\x20"("\x20newline\x20ModulePath\x20newline\x20")"\x20newline\x20.\x0aExample:
\x0amodule\x20golang.org/x/net\x0ago\x20directiveA\x20go\x20directive\x20sets\x20the\x20expected\x20language\x20version\x20for\x20the\x20module.\x20The\x0aversion\x20must\x20be\x20a\x20valid\x20Go\x20release\x20version:\x20a\x20positive\x20integer\x20followed\x20by\x20a\x20dot\x0aand\x20a\x20non-negative\x20integer\x20(for\x20example,\x201.9,\x201.14).
The\x20language\x20version\x20determines\x20which\x20language\x20features\x20are\x20available\x20when\x0acompiling\x20packages\x20in\x20the\x20module.\x20Language\x20features\x20present\x20in\x20that\x20version\x0awill\x20be\x20available\x20for\x20use.\x20Language\x20features\x20removed\x20in\x20earlier\x20versions,\x0aor\x20added\x20in\x20later\x20versions,\x20will\x20not\x20be\x20available.\x20The\x20language\x20version\x20does\x20not\x0aaffect\x20build\x20tags,\x20which\x20are\x20determined\x20by\x20the\x20Go\x20release\x20being\x20used.
\x0aThe\x20language\x20version\x20is\x20also\x20used\x20to\x20enable\x20features\x20in\x20the\x20go\x20command.\x20For\x0aexample,\x20automatic\x20go\x20version\x20of\x0a1.14\x20or\x20higher.
A\x20go.mod\x20file\x20may\x20contain\x20at\x20most\x20one\x20go\x20directive.\x20Most\x20commands\x20will\x20add\x20a\x0ago\x20directive\x20with\x20the\x20current\x20Go\x20version\x20if\x20one\x20is\x20not\x20present.
GoDirective\x20=\x20"go"\x20GoVersion\x20newline\x20.\x0aGoVersion\x20=\x20string\x20|\x20ident\x20.\x20\x20/*\x20valid\x20release\x20version;\x20see\x20above\x20*/\x0aExample:
\x0ago\x201.14\x0arequire\x20directiveA\x20require\x20directive\x20declares\x20a\x20minimum\x20required\x20version\x20of\x20a\x20given\x20module\x0adependency.\x20For\x20each\x20required\x20module\x20version,\x20the\x20go\x20command\x20loads\x20the\x0ago.mod\x20file\x20for\x20that\x20version\x20and\x20incorporates\x20the\x20requirements\x20from\x20that\x0afile.\x20Once\x20all\x20requirements\x20have\x20been\x20loaded,\x20the\x20go\x20command\x20resolves\x20them\x0ausing\x20
The\x20go\x20command\x20automatically\x20adds\x20//\x20indirect\x20comments\x20for\x20some\x0arequirements.\x20An\x20//\x20indirect\x20comment\x20indicates\x20that\x20no\x20package\x20from\x20the\x0arequired\x20module\x20is\x20directly\x20imported\x20by\x20any\x20package\x20in\x20the\x20main\x20module.\x0aThe\x20go\x20command\x20adds\x20an\x20indirect\x20requirement\x20when\x20the\x20selected\x20version\x20of\x20a\x0amodule\x20is\x20higher\x20than\x20what\x20is\x20already\x20implied\x20(transitively)\x20by\x20the\x20main\x0amodule's\x20other\x20dependencies.\x20That\x20may\x20occur\x20because\x20of\x20an\x20explicit\x20upgrade\x0a(go\x20get\x20-u),\x20removal\x20of\x20some\x20other\x20dependency\x20that\x20previously\x20imposed\x20the\x0arequirement\x20(go\x20mod\x20tidy),\x20or\x20a\x20dependency\x20that\x20imports\x20a\x20package\x20without\x0aa\x20corresponding\x20requirement\x20in\x20its\x20own\x20go.mod\x20file\x20(such\x20as\x20a\x20dependency\x0athat\x20lacks\x20a\x20go.mod\x20file\x20altogether).
RequireDirective\x20=\x20"require"\x20(\x20RequireSpec\x20|\x20"("\x20newline\x20{\x20RequireSpec\x20}\x20")"\x20newline\x20)\x20.\x0aRequireSpec\x20=\x20ModulePath\x20Version\x20newline\x20.\x0aExample:
\x0arequire\x20golang.org/x/net\x20v1.2.3\x0a\x0arequire\x20(\x0a\x20\x20\x20\x20golang.org/x/crypto\x20v1.4.5\x20//\x20indirect\x0a\x20\x20\x20\x20golang.org/x/text\x20v1.6.7\x0a)\x0aexclude\x20directiveAn\x20exclude\x20directive\x20prevents\x20a\x20module\x20version\x20from\x20being\x20loaded\x20by\x20the\x20go\x0acommand.\x20If\x20an\x20excluded\x20version\x20is\x20referenced\x20by\x20a\x20require\x20directive\x20in\x20a\x0ago.mod\x20file,\x20the\x20go\x20command\x20will\x20list\x20available\x20versions\x20for\x20the\x20module\x20(as\x0ashown\x20with\x20go\x20list\x20-m\x20-versions)\x20and\x20will\x20load\x20the\x20next\x20higher\x20non-excluded\x0aversion\x20instead.\x20Both\x20release\x20and\x20pre-release\x20versions\x20are\x20considered\x20for\x20this\x0apurpose,\x20but\x20pseudo-versions\x20are\x20not.\x20If\x20there\x20are\x20no\x20higher\x20versions,\x0athe\x20go\x20command\x20will\x20report\x20an\x20error.\x20Note\x20that\x20this\x20
exclude\x20directives\x20only\x20apply\x20in\x20the\x20main\x20module's\x20go.mod\x20file\x20and\x20are\x0aignored\x20in\x20other\x20modules.\x20See\x20
ExcludeDirective\x20=\x20"exclude"\x20(\x20ExcludeSpec\x20|\x20"("\x20newline\x20{\x20ExcludeSpec\x20}\x20")"\x20)\x20.\x0aExcludeSpec\x20=\x20ModulePath\x20Version\x20newline\x20.\x0aExample:
\x0aexclude\x20golang.org/x/net\x20v1.2.3\x0a\x0aexclude\x20(\x0a\x20\x20\x20\x20golang.org/x/crypto\x20v1.4.5\x0a\x20\x20\x20\x20golang.org/x/text\x20v1.6.7\x0a)\x0areplace\x20directiveA\x20replace\x20directive\x20replaces\x20the\x20contents\x20of\x20a\x20specific\x20version\x20of\x20a\x20module,\x0aor\x20all\x20versions\x20of\x20a\x20module,\x20with\x20contents\x20found\x20elsewhere.\x20The\x20replacement\x0amay\x20be\x20specified\x20with\x20either\x20another\x20module\x20path\x20and\x20version,\x20or\x20a\x0aplatform-specific\x20file\x20path.
If\x20a\x20version\x20is\x20present\x20on\x20the\x20left\x20side\x20of\x20the\x20arrow\x20(=>),\x20only\x20that\x20specific\x0aversion\x20of\x20the\x20module\x20is\x20replaced;\x20other\x20versions\x20will\x20be\x20accessed\x20normally.\x0aIf\x20the\x20left\x20version\x20is\x20omitted,\x20all\x20versions\x20of\x20the\x20module\x20are\x20replaced.
If\x20the\x20path\x20on\x20the\x20right\x20side\x20of\x20the\x20arrow\x20is\x20an\x20absolute\x20or\x20relative\x20path\x0a(beginning\x20with\x20./\x20or\x20../),\x20it\x20is\x20interpreted\x20as\x20the\x20local\x20file\x20path\x20to\x20the\x0areplacement\x20module\x20root\x20directory,\x20which\x20must\x20contain\x20a\x20go.mod\x20file.\x20The\x0areplacement\x20version\x20must\x20be\x20omitted\x20in\x20this\x20case.
If\x20the\x20path\x20on\x20the\x20right\x20side\x20is\x20not\x20a\x20local\x20path,\x20it\x20must\x20be\x20a\x20valid\x20module\x0apath.\x20In\x20this\x20case,\x20a\x20version\x20is\x20required.\x20The\x20same\x20module\x20version\x20must\x20not\x0aalso\x20appear\x20in\x20the\x20build\x20list.
\x0aRegardless\x20of\x20whether\x20a\x20replacement\x20is\x20specified\x20with\x20a\x20local\x20path\x20or\x20module\x0apath,\x20if\x20the\x20replacement\x20module\x20has\x20a\x20go.mod\x20file,\x20its\x20module\x20directive\x0amust\x20match\x20the\x20module\x20path\x20it\x20replaces.
replace\x20directives\x20only\x20apply\x20in\x20the\x20main\x20module's\x20go.mod\x20file\x0aand\x20are\x20ignored\x20in\x20other\x20modules.\x20See\x20
ReplaceDirective\x20=\x20"replace"\x20(\x20ReplaceSpec\x20|\x20"("\x20newline\x20{\x20ReplaceSpec\x20}\x20")"\x20newline\x20")"\x20)\x20.\x0aReplaceSpec\x20=\x20ModulePath\x20[\x20Version\x20]\x20"=>"\x20FilePath\x20newline\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20|\x20ModulePath\x20[\x20Version\x20]\x20"=>"\x20ModulePath\x20Version\x20newline\x20.\x0aFilePath\x20=\x20/*\x20platform-specific\x20relative\x20or\x20absolute\x20file\x20path\x20*/\x0aExample:
\x0areplace\x20golang.org/x/net\x20v1.2.3\x20=>\x20example.com/fork/net\x20v1.4.5\x0a\x0areplace\x20(\x0a\x20\x20\x20\x20golang.org/x/net\x20v1.2.3\x20=>\x20example.com/fork/net\x20v1.4.5\x0a\x20\x20\x20\x20golang.org/x/net\x20=>\x20example.com/fork/net\x20v1.4.5\x0a\x20\x20\x20\x20golang.org/x/net\x20v1.2.3\x20=>\x20./fork/net\x0a\x20\x20\x20\x20golang.org/x/net\x20=>\x20./fork/net\x0a)\x0aThe\x20go\x20command\x20automatically\x20updates\x20go.mod\x20when\x20it\x20uses\x20the\x20module\x20graph\x20if\x0asome\x20information\x20is\x20missing\x20or\x20go.mod\x20doesn't\x20accurately\x20reflect\x20reality.\x20\x20For\x0aexample,\x20consider\x20this\x20go.mod\x20file:
module\x20example.com/M\x0a\x0arequire\x20(\x0a\x20\x20\x20\x20example.com/A\x20v1\x0a\x20\x20\x20\x20example.com/B\x20v1.0.0\x0a\x20\x20\x20\x20example.com/C\x20v1.0.0\x0a\x20\x20\x20\x20example.com/D\x20v1.2.3\x0a\x20\x20\x20\x20example.com/E\x20dev\x0a)\x0a\x0aexclude\x20example.com/D\x20v1.2.3\x0aThe\x20update\x20rewrites\x20non-canonical\x20version\x20identifiers\x20to\x0aexample.com/A's\x20v1\x0abecomes\x20v1.0.0,\x20and\x20example.com/E's\x20dev\x20becomes\x20the\x20pseudo-version\x20for\x20the\x0alatest\x20commit\x20on\x20the\x20dev\x20branch,\x20perhaps\x20v0.0.0-20180523231146-b3f5c0f6e5f1.
The\x20update\x20modifies\x20requirements\x20to\x20respect\x20exclusions,\x20so\x20the\x20requirement\x20on\x0athe\x20excluded\x20example.com/D\x20v1.2.3\x20is\x20updated\x20to\x20use\x20the\x20next\x20available\x20version\x0aof\x20example.com/D,\x20perhaps\x20v1.2.4\x20or\x20v1.3.0.
The\x20update\x20removes\x20redundant\x20or\x20misleading\x20requirements.\x20For\x20example,\x20if\x0aexample.com/A\x20v1.0.0\x20itself\x20requires\x20example.com/B\x20v1.2.0\x20and\x20example.com/C\x20v1.0.0,\x20then\x20go.mod's\x20requirement\x20of\x20example.com/B\x20v1.0.0\x20is\x20misleading\x0a(superseded\x20by\x20example.com/A's\x20need\x20for\x20v1.2.0),\x20and\x20its\x20requirement\x20of\x0aexample.com/C\x20v1.0.0\x20is\x20redundant\x20(implied\x20by\x20example.com/A's\x20need\x20for\x20the\x0asame\x20version),\x20so\x20both\x20will\x20be\x20removed.\x20If\x20the\x20main\x20module\x20contains\x20packages\x0athat\x20directly\x20import\x20packages\x20from\x20example.com/B\x20or\x20example.com/C,\x20then\x20the\x0arequirements\x20will\x20be\x20kept\x20but\x20updated\x20to\x20the\x20actual\x20versions\x20being\x20used.
Finally,\x20the\x20update\x20reformats\x20the\x20go.mod\x20in\x20a\x20canonical\x20formatting,\x20so\x0athat\x20future\x20mechanical\x20changes\x20will\x20result\x20in\x20minimal\x20diffs.\x20The\x20go\x20command\x0awill\x20not\x20update\x20go.mod\x20if\x20only\x20formatting\x20changes\x20are\x20needed.
Because\x20the\x20module\x20graph\x20defines\x20the\x20meaning\x20of\x20import\x20statements,\x20any\x20commands\x0athat\x20load\x20packages\x20also\x20use\x20and\x20therefore\x20update\x20go.mod,\x20including\x20go\x20build,\x0ago\x20get,\x20go\x20install,\x20go\x20list,\x20go\x20test,\x20go\x20mod\x20graph,\x20go\x20mod\x20tidy,\x20and\x0ago\x20mod\x20why.
The\x20-mod=readonly\x20flag\x20prevents\x20commands\x20from\x20automatically\x20updating\x0ago.mod.\x20However,\x20if\x20a\x20command\x20needs\x20to\x20perform\x20an\x20action\x20that\x20would\x0aupdate\x20to\x20go.mod,\x20it\x20will\x20report\x20an\x20error.\x20For\x20example,\x20if\x0ago\x20build\x20is\x20asked\x20to\x20build\x20a\x20package\x20not\x20provided\x20by\x20any\x20module\x20in\x20the\x20build\x0alist,\x20go\x20build\x20will\x20report\x20an\x20error\x20instead\x20of\x20looking\x20up\x20the\x20module\x20and\x0aupdating\x20requirements\x20in\x20go.mod.
Go\x20uses\x20an\x20algorithm\x20called\x20Minimal\x20version\x20selection\x20(MVS)\x20to\x20select\x0aa\x20set\x20of\x20module\x20versions\x20to\x20use\x20when\x20building\x20packages.\x20MVS\x20is\x20described\x20in\x0adetail\x20in\x20
Conceptually,\x20MVS\x20operates\x20on\x20a\x20directed\x20graph\x20of\x20modules,\x20specified\x20with\x0ago.mod\x20files.\x20Each\x20vertex\x20in\x20the\x20graph\x20represents\x20a\x0amodule\x20version.\x20Each\x20edge\x20represents\x20a\x20minimum\x20required\x20version\x20of\x20a\x20dependency,\x0aspecified\x20using\x20a\x20require\x0adirective.\x20replace\x20and\x20exclude\x0adirectives\x20in\x20the\x20main\x20module's\x20go.mod\x20file\x20modify\x20the\x20graph.
MVS\x20produces\x20the\x20
MVS\x20starts\x20at\x20the\x20main\x20module\x20(a\x20special\x20vertex\x20in\x20the\x20graph\x20that\x20has\x20no\x0aversion)\x20and\x20traverses\x20the\x20graph,\x20tracking\x20the\x20highest\x20required\x20version\x20of\x20each\x0amodule.\x20At\x20the\x20end\x20of\x20the\x20traversal,\x20the\x20highest\x20required\x20versions\x20comprise\x20the\x0abuild\x20list:\x20they\x20are\x20the\x20minimum\x20versions\x20that\x20satisfy\x20all\x20requirements.
\x0aThe\x20build\x20list\x20may\x20be\x20inspected\x20with\x20the\x20command\x20go\x20list\x20-m\x20all.\x20Unlike\x20other\x20dependency\x20management\x20systems,\x20the\x20build\x20list\x20is\x0anot\x20saved\x20in\x20a\x20"lock"\x20file.\x20MVS\x20is\x20deterministic,\x20and\x20the\x20build\x20list\x20doesn't\x0achange\x20when\x20new\x20versions\x20of\x20dependencies\x20are\x20released,\x20so\x20MVS\x20is\x20used\x20to\x20compute\x0ait\x20at\x20the\x20beginning\x20of\x20every\x20module-aware\x20command.
Consider\x20the\x20example\x20in\x20the\x20diagram\x20below.\x20The\x20main\x20module\x20requires\x20module\x20A\x0aat\x20version\x201.2\x20or\x20higher\x20and\x20module\x20B\x20at\x20version\x201.2\x20or\x20higher.\x20A\x201.2\x20and\x20B\x201.2\x0arequire\x20C\x201.3\x20and\x20C\x201.4,\x20respectively.\x20C\x201.3\x20and\x20C\x201.4\x20both\x20require\x20D\x201.2.
\x0aMVS\x20visits\x20and\x20loads\x20the\x20go.mod\x20file\x20for\x20each\x20of\x20the\x20module\x20versions\x0ahighlighted\x20in\x20blue.\x20At\x20the\x20end\x20of\x20the\x20graph\x20traversal,\x20MVS\x20returns\x20a\x20build\x20list\x0acontaining\x20the\x20bolded\x20versions:\x20A\x201.2,\x20B\x201.2,\x20C\x201.4,\x20and\x20D\x201.2.\x20Note\x20that\x20higher\x0aversions\x20of\x20B\x20and\x20D\x20are\x20available\x20but\x20MVS\x20does\x20not\x20select\x20them,\x20since\x20nothing\x0arequires\x20them.
The\x20content\x20of\x20a\x20module\x20(including\x20its\x20go.mod\x20file)\x20may\x20be\x20replaced\x20using\x20a\x0areplace\x20directive\x20in\x20the\x20the\x20main\x20module's\x20go.mod\x20file.\x0aA\x20replace\x20directive\x20may\x20apply\x20to\x20a\x20specific\x20version\x20of\x20a\x20module\x20or\x20to\x20all\x0aversions\x20of\x20a\x20module.
Replacements\x20change\x20the\x20module\x20graph,\x20since\x20a\x20replacement\x20module\x20may\x20have\x0adifferent\x20dependencies\x20than\x20replaced\x20versions.
\x0aConsider\x20the\x20example\x20below,\x20where\x20C\x201.4\x20has\x20been\x20replaced\x20with\x20R.\x20R\x20depends\x20on\x20D\x0a1.3\x20instead\x20of\x20D\x201.2,\x20so\x20MVS\x20returns\x20a\x20build\x20list\x20containing\x20A\x201.2,\x20B\x201.2,\x20C\x201.4\x0a(replaced\x20with\x20R),\x20and\x20D\x201.3.
\x0aA\x20module\x20may\x20also\x20be\x20excluded\x20at\x20specific\x20versions\x20using\x20an\x20exclude\x0adirective\x20in\x20the\x20main\x20module's\x20go.mod\x20file.
Exclusions\x20also\x20change\x20the\x20module\x20graph.\x20When\x20a\x20version\x20is\x20excluded,\x20it\x20is\x0aremoved\x20from\x20the\x20module\x20graph,\x20and\x20requirements\x20on\x20it\x20are\x20redirected\x20to\x20the\x0anext\x20higher\x20version.
\x0aConsider\x20the\x20example\x20below.\x20C\x201.3\x20has\x20been\x20excluded.\x20MVS\x20will\x20act\x20as\x20if\x20A\x201.2\x0arequired\x20C\x201.4\x20(the\x20next\x20higher\x20version)\x20instead\x20of\x20C\x201.3.
\x0aThe\x20go\x20get\x20command\x20may\x20be\x20used\x20to\x20upgrade\x20a\x20set\x20of\x20modules.\x20To\x0aperform\x20an\x20upgrade,\x20the\x20go\x20command\x20changes\x20the\x20module\x20graph\x20before\x20running\x20MVS\x0aby\x20adding\x20edges\x20from\x20visited\x20versions\x20to\x20upgraded\x20versions.
Consider\x20the\x20example\x20below.\x20Module\x20B\x20may\x20be\x20upgraded\x20from\x201.2\x20to\x201.3,\x20C\x20may\x20be\x0aupgraded\x20from\x201.3\x20to\x201.4,\x20and\x20D\x20may\x20be\x20upgraded\x20from\x201.2\x20to\x201.3.
\x0aUpgrades\x20(and\x20downgrades)\x20may\x20add\x20or\x20remove\x20indirect\x20dependencies.\x20In\x20this\x20case,\x0aE\x201.1\x20and\x20F\x201.1\x20appear\x20in\x20the\x20build\x20list\x20after\x20the\x20upgrade,\x20since\x20E\x201.1\x20is\x0arequired\x20by\x20B\x201.3.
\x0aTo\x20preserve\x20upgrades,\x20the\x20go\x20command\x20updates\x20the\x20requirements\x20in\x20go.mod.\x20\x20It\x0awill\x20change\x20the\x20requirement\x20on\x20B\x20to\x20version\x201.3.\x20It\x20will\x20also\x20add\x20requirements\x0aon\x20C\x201.4\x20and\x20D\x201.3\x20with\x20//\x20indirect\x20comments,\x20since\x20those\x20versions\x20would\x20not\x0abe\x20selected\x20otherwise.
The\x20go\x20get\x20command\x20may\x20also\x20be\x20used\x20to\x20downgrade\x20a\x20set\x20of\x0amodules.\x20To\x20perform\x20a\x20downgrade,\x20the\x20go\x20command\x20changes\x20the\x20module\x20graph\x20by\x0aremoving\x20versions\x20above\x20the\x20downgraded\x20versions.\x20It\x20also\x20removes\x20versions\x20of\x0aother\x20modules\x20that\x20depend\x20on\x20removed\x20versions,\x20since\x20they\x20may\x20not\x20be\x20compatible\x0awith\x20the\x20downgraded\x20versions\x20of\x20their\x20dependencies.\x20If\x20the\x20main\x20module\x20requires\x0aa\x20module\x20version\x20removed\x20by\x20downgrading,\x20the\x20requirement\x20is\x20changed\x20to\x20a\x0aprevious\x20version\x20that\x20has\x20not\x20been\x20removed.\x20If\x20no\x20previous\x20version\x20is\x20available,\x0athe\x20requirement\x20is\x20dropped.
Consider\x20the\x20example\x20below.\x20Suppose\x20that\x20a\x20problem\x20was\x20found\x20with\x20C\x201.4,\x20so\x20we\x0adowngrade\x20to\x20C\x201.3.\x20C\x201.4\x20is\x20removed\x20from\x20the\x20module\x20graph.\x20B\x201.2\x20is\x20also\x0aremoved,\x20since\x20it\x20requires\x20C\x201.4\x20or\x20higher.\x20The\x20main\x20module's\x20requirement\x20on\x20B\x0ais\x20changed\x20to\x201.1.
\x0ago\x20get\x20can\x20also\x20remove\x20dependencies\x20entirely,\x20using\x20an\x20@none\x0asuffix\x20after\x20an\x20argument.\x20This\x20works\x20similarly\x20to\x20a\x20downgrade.\x20All\x20versions\x0aof\x20the\x20named\x20module\x20are\x20removed\x20from\x20the\x20module\x20graph.
Most\x20go\x20commands\x20may\x20run\x20in\x20Module-aware\x20mode\x20or\x20GOPATH\x20mode.\x20In\x0amodule-aware\x20mode,\x20the\x20go\x20command\x20uses\x20go.mod\x20files\x20to\x20find\x20versioned\x0adependencies,\x20and\x20it\x20typically\x20loads\x20packages\x20out\x20of\x20the\x20GOPATH\x0amode,\x20the\x20go\x20command\x20ignores\x20modules;\x20it\x20looks\x20in\x20vendor\x20directories\x20and\x20in\x0aGOPATH\x20to\x20find\x20dependencies.
Module-aware\x20mode\x20is\x20active\x20by\x20default\x20whenever\x20a\x20go.mod\x20file\x20is\x20found\x20in\x20the\x0acurrent\x20directory\x20or\x20in\x20any\x20parent\x20directory.\x20For\x20more\x20fine-grained\x20control,\x20the\x0aGO111MODULE\x20environment\x20variable\x20may\x20be\x20set\x20to\x20one\x20of\x20three\x20values:\x20on,\x0aoff,\x20or\x20auto.
GO111MODULE=off,\x20the\x20go\x20command\x20ignores\x20go.mod\x20files\x20and\x20runs\x20in\x0aGOPATH\x20mode.GO111MODULE=on,\x20the\x20go\x20command\x20runs\x20in\x20module-aware\x20mode,\x20even\x20when\x0ano\x20go.mod\x20file\x20is\x20present.\x20Not\x20all\x20commands\x20work\x20without\x20a\x20go.mod\x20file:\x0asee\x20GO111MODULE=auto\x20or\x20is\x20unset,\x20the\x20go\x20command\x20runs\x20in\x20module-aware\x0amode\x20if\x20a\x20go.mod\x20file\x20is\x20present\x20in\x20the\x20current\x20directory\x20or\x20any\x20parent\x0adirectory\x20(the\x20default\x20behavior).In\x20module-aware\x20mode,\x20GOPATH\x20no\x20longer\x20defines\x20the\x20meaning\x20of\x20imports\x20during\x20a\x0abuild,\x20but\x20it\x20still\x20stores\x20downloaded\x20dependencies\x20(in\x20GOPATH/pkg/mod;\x20see\x0aGOPATH/bin,\x20unless\x0aGOBIN\x20is\x20set).
When\x20using\x20modules,\x20the\x20go\x20command\x20typically\x20satisfies\x20dependencies\x20by\x0adownloading\x20modules\x20from\x20their\x20sources\x20into\x20the\x20module\x20cache,\x20then\x20loading\x0apackages\x20from\x20those\x20downloaded\x20copies.\x20Vendoring\x20may\x20be\x20used\x20to\x20allow\x0ainteroperation\x20with\x20older\x20versions\x20of\x20Go,\x20or\x20to\x20ensure\x20that\x20all\x20files\x20used\x20for\x20a\x0abuild\x20are\x20stored\x20in\x20a\x20single\x20file\x20tree.
The\x20go\x20mod\x20vendor\x20command\x20constructs\x20a\x20directory\x20named\x20vendor\x20in\x20the\x20go\x20mod\x20tidy\x20and\x20other\x20module\x20commands,\x20ignore\x20are\x20not\x20considered\x20when\x0aconstructing\x20the\x20vendor\x20directory.
go\x20mod\x20vendor\x20also\x20creates\x20the\x20file\x20vendor/modules.txt\x20that\x20contains\x20a\x20list\x0aof\x20vendored\x20packages\x20and\x20the\x20module\x20versions\x20they\x20were\x20copied\x20from.\x20When\x0avendoring\x20is\x20enabled,\x20this\x20manifest\x20is\x20used\x20as\x20a\x20source\x20of\x20module\x20version\x0ainformation,\x20as\x20reported\x20by\x20go\x20list\x20-m\x20and\x20go\x20version\x20-m.\x20When\x20the\x20go\x20command\x20reads\x20vendor/modules.txt,\x20it\x20checks\x0athat\x20the\x20module\x20versions\x20are\x20consistent\x20with\x20go.mod.\x20If\x20go.mod\x20has\x20changed\x0asince\x20vendor/modules.txt\x20was\x20generated,\x20the\x20go\x20command\x20will\x20report\x20an\x20error.\x0ago\x20mod\x20vendor\x20should\x20be\x20run\x20again\x20to\x20update\x20the\x20vendor\x20directory.
If\x20the\x20vendor\x20directory\x20is\x20present\x20in\x20the\x20main\x20module's\x20root\x20directory,\x20it\x0awill\x20be\x20used\x20automatically\x20if\x20the\x20go\x20version\x20in\x20the\x20main\x0amodule's\x20go.mod\x20file\x20is\x201.14\x20or\x20higher.\x20To\x20explicitly\x0aenable\x20vendoring,\x20invoke\x20the\x20go\x20command\x20with\x20the\x20flag\x20-mod=vendor.\x20To\x0adisable\x20vendoring,\x20use\x20the\x20flag\x20-mod=mod.
When\x20vendoring\x20is\x20enabled,\x20go\x20build\x20and\x0ago\x20test\x20load\x20packages\x20from\x20the\x20vendor\x20directory\x20instead\x20of\x20accessing\x20the\x0anetwork\x20or\x20the\x20local\x20module\x20cache.\x20The\x20go\x20list\x20-m\x20command\x20only\x0aprints\x20information\x20about\x20modules\x20listed\x20in\x20go.mod.\x20go\x20mod\x20commands\x20such\x20as\x0ago\x20mod\x20download\x20and\x20go\x20mod\x20tidy\x20do\x20not\x0awork\x20differently\x20when\x20vendoring\x20is\x20enabled\x20and\x20will\x20still\x20download\x20modules\x20and\x0aaccess\x20the\x20module\x20cache.\x20go\x20get\x20also\x20does\x20not\x20work\x20differently\x20when\x0avendoring\x20is\x20enabled.
Unlike\x20GOPATH,\x20the\x20go\x0acommand\x20ignores\x20vendor\x20directories\x20in\x20locations\x20other\x20than\x20the\x20main\x20module's\x0aroot\x20directory.
go\x20getUsage:
\x0ago\x20get\x20[-d]\x20[-t]\x20[-u]\x20[build\x20flags]\x20[packages]\x0aExamples:
\x0a#\x20Install\x20the\x20latest\x20version\x20of\x20a\x20tool.\x0a$\x20go\x20get\x20golang.org/x/tools/cmd/goimports\x0a\x0a#\x20Upgrade\x20a\x20specific\x20module.\x0a$\x20go\x20get\x20-d\x20golang.org/x/net\x0a\x0a#\x20Upgrade\x20modules\x20that\x20provide\x20packages\x20imported\x20by\x20packages\x20in\x20the\x20main\x20module.\x0a$\x20go\x20get\x20-d\x20-u\x20./...\x0a\x0a#\x20Upgrade\x20or\x20downgrade\x20to\x20a\x20specific\x20version\x20of\x20a\x20module.\x0a$\x20go\x20get\x20-d\x20golang.org/x/text@v0.3.2\x0a\x0a#\x20Update\x20to\x20the\x20commit\x20on\x20the\x20module's\x20master\x20branch.\x0a$\x20go\x20get\x20-d\x20golang.org/x/text@master\x0a\x0a#\x20Remove\x20a\x20dependency\x20on\x20a\x20module\x20and\x20downgrade\x20modules\x20that\x20require\x20it\x0a#\x20to\x20versions\x20that\x20don't\x20require\x20it.\x0a$\x20go\x20get\x20-d\x20golang.org/x/text@none\x0aThe\x20go\x20get\x20command\x20updates\x20module\x20dependencies\x20in\x20the\x20go.mod\x0afile\x20for\x20the\x20
The\x20first\x20step\x20is\x20to\x20determine\x20which\x20modules\x20to\x20update.\x20go\x20get\x20accepts\x20a\x20list\x0aof\x20packages,\x20package\x20patterns,\x20and\x20module\x20paths\x20as\x20arguments.\x20If\x20a\x20package\x0aargument\x20is\x20specified,\x20go\x20get\x20updates\x20the\x20module\x20that\x20provides\x20the\x20package.\x0aIf\x20a\x20package\x20pattern\x20is\x20specified\x20(for\x20example,\x20all\x20or\x20a\x20path\x20with\x20a\x20...\x0awildcard),\x20go\x20get\x20expands\x20the\x20pattern\x20to\x20a\x20set\x20of\x20packages,\x20then\x20updates\x20the\x0amodules\x20that\x20provide\x20the\x20packages.\x20If\x20an\x20argument\x20names\x20a\x20module\x20but\x20not\x20a\x0apackage\x20(for\x20example,\x20the\x20module\x20golang.org/x/net\x20has\x20no\x20package\x20in\x20its\x20root\x0adirectory),\x20go\x20get\x20will\x20update\x20the\x20module\x20but\x20will\x20not\x20build\x20a\x20package.\x20If\x20no\x0aarguments\x20are\x20specified,\x20go\x20get\x20acts\x20as\x20if\x20.\x20were\x20specified\x20(the\x20package\x20in\x0athe\x20current\x20directory);\x20this\x20may\x20be\x20used\x20together\x20with\x20the\x20-u\x20flag\x20to\x20update\x0amodules\x20that\x20provide\x20imported\x20packages.
Each\x20argument\x20may\x20include\x20a\x20version\x20query\x20suffix\x20indicating\x20the\x0adesired\x20version,\x20as\x20in\x20go\x20get\x20golang.org/x/text@v0.3.0.\x20A\x20version\x20query\x0asuffix\x20consists\x20of\x20an\x20@\x20symbol\x20followed\x20by\x20a\x20v0.3.0),\x20a\x20version\x20prefix\x20(v0.3),\x0aa\x20branch\x20or\x20tag\x20name\x20(master),\x20a\x20revision\x20(1234abcd),\x20or\x20one\x20of\x20the\x20special\x0aqueries\x20latest,\x20upgrade,\x20patch,\x20or\x20none.\x20If\x20no\x20version\x20is\x20given,\x0ago\x20get\x20uses\x20the\x20@upgrade\x20query.
Once\x20go\x20get\x20has\x20resolved\x20its\x20arguments\x20to\x20specific\x20modules\x20and\x20versions,\x20go\x20get\x20will\x20add,\x20change,\x20or\x20remove\x20require\x20directives\x20in\x20the\x0amain\x20module's\x20go.mod\x20file\x20to\x20ensure\x20the\x20modules\x20remain\x20at\x20the\x20desired\x0aversions\x20in\x20the\x20future.\x20Note\x20that\x20required\x20versions\x20in\x20go.mod\x20files\x20are\x0aminimum\x20versions\x20and\x20may\x20be\x20increased\x20automatically\x20as\x20new\x20dependencies\x20are\x0aadded.\x20See\x20
Other\x20modules\x20may\x20be\x20upgraded\x20when\x20a\x20module\x20named\x20on\x20the\x20command\x20line\x20is\x20added,\x0aupgraded,\x20or\x20downgraded\x20if\x20the\x20new\x20version\x20of\x20the\x20named\x20module\x20requires\x20other\x0amodules\x20at\x20higher\x20versions.\x20For\x20example,\x20suppose\x20module\x20example.com/a\x20is\x0aupgraded\x20to\x20version\x20v1.5.0,\x20and\x20that\x20version\x20requires\x20module\x20example.com/b\x0aat\x20version\x20v1.2.0.\x20If\x20module\x20example.com/b\x20is\x20currently\x20required\x20at\x20version\x0av1.1.0,\x20go\x20get\x20example.com/a@v1.5.0\x20will\x20also\x20upgrade\x20example.com/b\x20to\x0av1.2.0.
Other\x20modules\x20may\x20be\x20downgraded\x20when\x20a\x20module\x20named\x20on\x20the\x20command\x20line\x20is\x0adowngraded\x20or\x20removed.\x20To\x20continue\x20the\x20above\x20example,\x20suppose\x20module\x0aexample.com/b\x20is\x20downgraded\x20to\x20v1.1.0.\x20Module\x20example.com/a\x20would\x20also\x20be\x0adowngraded\x20to\x20a\x20version\x20that\x20requires\x20example.com/b\x20at\x20version\x20v1.1.0\x20or\x0alower.
A\x20module\x20requirement\x20may\x20be\x20removed\x20using\x20the\x20version\x20suffix\x20@none.\x20This\x20is\x20a\x0aspecial\x20kind\x20of\x20downgrade.\x20Modules\x20that\x20depend\x20on\x20the\x20removed\x20module\x20will\x20be\x0adowngraded\x20or\x20removed\x20as\x20needed.\x20A\x20module\x20requirement\x20may\x20be\x20removed\x20even\x20if\x20one\x0aor\x20more\x20of\x20its\x20packages\x20are\x20imported\x20by\x20packages\x20in\x20the\x20main\x20module.\x20In\x20this\x0acase,\x20the\x20next\x20build\x20command\x20may\x20add\x20a\x20new\x20module\x20requirement.
If\x20a\x20module\x20is\x20needed\x20at\x20two\x20different\x20versions\x20(specified\x20explicitly\x20in\x20command\x0aline\x20arguments\x20or\x20to\x20satisfy\x20upgrades\x20and\x20downgrades),\x20go\x20get\x20will\x20report\x20an\x0aerror.
After\x20go\x20get\x20updates\x20the\x20go.mod\x20file,\x20it\x20builds\x20the\x20packages\x20named\x0aon\x20the\x20command\x20line.\x20Executables\x20will\x20be\x20installed\x20in\x20the\x20directory\x20named\x20by\x0athe\x20GOBIN\x20environment\x20variable,\x20which\x20defaults\x20to\x20$GOPATH/bin\x20or\x0a$HOME/go/bin\x20if\x20the\x20GOPATH\x20environment\x20variable\x20is\x20not\x20set.
go\x20get\x20supports\x20the\x20following\x20flags:
-d\x20flag\x20tells\x20go\x20get\x20not\x20to\x20build\x20or\x20install\x20packages.\x20When\x20-d\x20is\x0aused,\x20go\x20get\x20will\x20only\x20manage\x20dependencies\x20in\x20go.mod.-u\x20flag\x20tells\x20go\x20get\x20to\x20upgrade\x20modules\x20providing\x20packages\x0aimported\x20directly\x20or\x20indirectly\x20by\x20packages\x20named\x20on\x20the\x20command\x20line.\x0aEach\x20module\x20selected\x20by\x20-u\x20will\x20be\x20upgraded\x20to\x20its\x20latest\x20version\x20unless\x0ait\x20is\x20already\x20required\x20at\x20a\x20higher\x20version\x20(a\x20pre-release).-u=patch\x20flag\x20(not\x20-u\x20patch)\x20also\x20tells\x20go\x20get\x20to\x20upgrade\x0adependencies,\x20but\x20go\x20get\x20will\x20upgrade\x20each\x20dependency\x20to\x20the\x20latest\x20patch\x0aversion\x20(similar\x20to\x20the\x20@patch\x20version\x20query).-t\x20flag\x20tells\x20go\x20get\x20to\x20consider\x20modules\x20needed\x20to\x20build\x20tests\x0aof\x20packages\x20named\x20on\x20the\x20command\x20line.\x20When\x20-t\x20and\x20-u\x20are\x20used\x20together,\x0ago\x20get\x20will\x20update\x20test\x20dependencies\x20as\x20well.-insecure\x20flag\x20should\x20no\x20longer\x20be\x20used.\x20It\x20permits\x20go\x20get\x20to\x20resolve\x0acustom\x20import\x20paths\x20and\x20fetch\x20from\x20repositories\x20and\x20module\x20proxies\x20using\x0ainsecure\x20schemes\x20such\x20as\x20HTTP.\x20The\x20GOINSECURE\x20go\x20list\x20-mUsage:
\x0ago\x20list\x20-m\x20[-u]\x20[-versions]\x20[list\x20flags]\x20[modules]\x0aExample:
\x0a$\x20go\x20list\x20-m\x20all\x0a$\x20go\x20list\x20-m\x20-versions\x20example.com/m\x0a$\x20go\x20list\x20-m\x20-json\x20example.com/m@latest\x0aThe\x20-m\x20flag\x20causes\x20go\x20list\x20to\x20list\x20modules\x20instead\x20of\x20packages.\x20In\x20this\x0amode,\x20the\x20arguments\x20to\x20go\x20list\x20may\x20be\x20modules,\x20module\x20patterns\x20(containing\x20the\x0a...\x20wildcard),\x20all,\x20which\x20matches\x20all\x20modules\x20in\x20the\x20
When\x20listing\x20modules,\x20the\x20-f\x20flag\x20still\x20specifies\x20a\x20format\x20template\x20applied\x0ato\x20a\x20Go\x20struct,\x20but\x20now\x20a\x20Module\x20struct:
type\x20Module\x20struct\x20{\x0a\x20\x20\x20\x20Path\x20\x20\x20\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20module\x20path\x0a\x20\x20\x20\x20Version\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20module\x20version\x0a\x20\x20\x20\x20Versions\x20\x20[]string\x20\x20\x20\x20\x20//\x20available\x20module\x20versions\x20(with\x20-versions)\x0a\x20\x20\x20\x20Replace\x20\x20\x20*Module\x20\x20\x20\x20\x20\x20//\x20replaced\x20by\x20this\x20module\x0a\x20\x20\x20\x20Time\x20\x20\x20\x20\x20\x20*time.Time\x20\x20\x20//\x20time\x20version\x20was\x20created\x0a\x20\x20\x20\x20Update\x20\x20\x20\x20*Module\x20\x20\x20\x20\x20\x20//\x20available\x20update,\x20if\x20any\x20(with\x20-u)\x0a\x20\x20\x20\x20Main\x20\x20\x20\x20\x20\x20bool\x20\x20\x20\x20\x20\x20\x20\x20\x20//\x20is\x20this\x20the\x20main\x20module?\x0a\x20\x20\x20\x20Indirect\x20\x20bool\x20\x20\x20\x20\x20\x20\x20\x20\x20//\x20is\x20this\x20module\x20only\x20an\x20indirect\x20dependency\x20of\x20main\x20module?\x0a\x20\x20\x20\x20Dir\x20\x20\x20\x20\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20directory\x20holding\x20files\x20for\x20this\x20module,\x20if\x20any\x0a\x20\x20\x20\x20GoMod\x20\x20\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20path\x20to\x20go.mod\x20file\x20for\x20this\x20module,\x20if\x20any\x0a\x20\x20\x20\x20GoVersion\x20string\x20\x20\x20\x20\x20\x20\x20//\x20go\x20version\x20used\x20in\x20module\x0a\x20\x20\x20\x20Error\x20\x20\x20\x20\x20*ModuleError\x20//\x20error\x20loading\x20module\x0a}\x0a\x0atype\x20ModuleError\x20struct\x20{\x0a\x20\x20\x20\x20Err\x20string\x20//\x20the\x20error\x20itself\x0a}\x0aThe\x20default\x20output\x20is\x20to\x20print\x20the\x20module\x20path\x20and\x20then\x20information\x20about\x20the\x0aversion\x20and\x20replacement\x20if\x20any.\x20For\x20example,\x20go\x20list\x20-m\x20all\x20might\x20print:
example.com/main/module\x0agolang.org/x/text\x20v0.3.0\x20=>\x20/tmp/text\x0arsc.io/pdf\x20v0.1.1\x0aThe\x20Module\x20struct\x20has\x20a\x20String\x20method\x20that\x20formats\x20this\x20line\x20of\x20output,\x20so\x0athat\x20the\x20default\x20format\x20is\x20equivalent\x20to\x20-f\x20'{{.String}}'.
Note\x20that\x20when\x20a\x20module\x20has\x20been\x20replaced,\x20its\x20Replace\x20field\x20describes\x20the\x0areplacement\x20module\x20module,\x20and\x20its\x20Dir\x20field\x20is\x20set\x20to\x20the\x20replacement\x0amodule's\x20source\x20code,\x20if\x20present.\x20(That\x20is,\x20if\x20Replace\x20is\x20non-nil,\x20then\x20Dir\x0ais\x20set\x20to\x20Replace.Dir,\x20with\x20no\x20access\x20to\x20the\x20replaced\x20source\x20code.)
The\x20-u\x20flag\x20adds\x20information\x20about\x20available\x20upgrades.\x20When\x20the\x20latest\x20version\x0aof\x20a\x20given\x20module\x20is\x20newer\x20than\x20the\x20current\x20one,\x20list\x20-u\x20sets\x20the\x20module's\x0aUpdate\x20field\x20to\x20information\x20about\x20the\x20newer\x20module.\x20The\x20module's\x20String\x0amethod\x20indicates\x20an\x20available\x20upgrade\x20by\x20formatting\x20the\x20newer\x20version\x20in\x0abrackets\x20after\x20the\x20current\x20version.\x20For\x20example,\x20go\x20list\x20-m\x20-u\x20all\x20might\x0aprint:
example.com/main/module\x0agolang.org/x/text\x20v0.3.0\x20[v0.4.0]\x20=>\x20/tmp/text\x0arsc.io/pdf\x20v0.1.1\x20[v0.1.2]\x0a(For\x20tools,\x20go\x20list\x20-m\x20-u\x20-json\x20all\x20may\x20be\x20more\x20convenient\x20to\x20parse.)
The\x20-versions\x20flag\x20causes\x20list\x20to\x20set\x20the\x20module's\x20Versions\x20field\x20to\x20a\x0alist\x20of\x20all\x20known\x20versions\x20of\x20that\x20module,\x20ordered\x20according\x20to\x20semantic\x0aversioning,\x20lowest\x20to\x20highest.\x20The\x20flag\x20also\x20changes\x20the\x20default\x20output\x20format\x0ato\x20display\x20the\x20module\x20path\x20followed\x20by\x20the\x20space-separated\x20version\x20list.
The\x20template\x20function\x20module\x20takes\x20a\x20single\x20string\x20argument\x20that\x20must\x20be\x20a\x0amodule\x20path\x20or\x20query\x20and\x20returns\x20the\x20specified\x20module\x20as\x20a\x20Module\x20struct.\x20If\x0aan\x20error\x20occurs,\x20the\x20result\x20will\x20be\x20a\x20Module\x20struct\x20with\x20a\x20non-nil\x20Error\x0afield.
go\x20mod\x20downloadUsage:
\x0ago\x20mod\x20download\x20[-json]\x20[-x]\x20[modules]\x0aExample:
\x0a$\x20go\x20mod\x20download\x0a$\x20go\x20mod\x20download\x20golang.org/x/mod@v0.2.0\x0aThe\x20go\x20mod\x20download\x20command\x20downloads\x20the\x20named\x20modules\x20into\x20the\x20path@version.\x20With\x20no\x20arguments,\x0adownload\x20applies\x20to\x20all\x20dependencies\x20of\x20the\x20
The\x20go\x20command\x20will\x20automatically\x20download\x20modules\x20as\x20needed\x20during\x20ordinary\x0aexecution.\x20The\x20go\x20mod\x20download\x20command\x20is\x20useful\x20mainly\x20for\x20pre-filling\x20the\x0amodule\x20cache\x20or\x20for\x20loading\x20data\x20to\x20be\x20served\x20by\x20a\x20
By\x20default,\x20download\x20writes\x20nothing\x20to\x20standard\x20output.\x20It\x20prints\x20progress\x0amessages\x20and\x20errors\x20to\x20standard\x20error.
The\x20-json\x20flag\x20causes\x20download\x20to\x20print\x20a\x20sequence\x20of\x20JSON\x20objects\x20to\x0astandard\x20output,\x20describing\x20each\x20downloaded\x20module\x20(or\x20failure),\x20corresponding\x0ato\x20this\x20Go\x20struct:
type\x20Module\x20struct\x20{\x0a\x20\x20\x20\x20Path\x20\x20\x20\x20\x20string\x20//\x20module\x20path\x0a\x20\x20\x20\x20Version\x20\x20string\x20//\x20module\x20version\x0a\x20\x20\x20\x20Error\x20\x20\x20\x20string\x20//\x20error\x20loading\x20module\x0a\x20\x20\x20\x20Info\x20\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20.info\x20file\x0a\x20\x20\x20\x20GoMod\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20.mod\x20file\x0a\x20\x20\x20\x20Zip\x20\x20\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20.zip\x20file\x0a\x20\x20\x20\x20Dir\x20\x20\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20source\x20root\x20directory\x0a\x20\x20\x20\x20Sum\x20\x20\x20\x20\x20\x20string\x20//\x20checksum\x20for\x20path,\x20version\x20(as\x20in\x20go.sum)\x0a\x20\x20\x20\x20GoModSum\x20string\x20//\x20checksum\x20for\x20go.mod\x20(as\x20in\x20go.sum)\x0a}\x0aThe\x20-x\x20flag\x20causes\x20download\x20to\x20print\x20the\x20commands\x20download\x20executes\x0ato\x20standard\x20error.
go\x20mod\x20editUsage:
\x0ago\x20mod\x20edit\x20[editing\x20flags]\x20[-fmt|-print|-json]\x20[go.mod]\x0aExample:
\x0a#\x20Add\x20a\x20replace\x20directive.\x0a$\x20go\x20mod\x20edit\x20-replace\x20example.com/a@v1.0.0=./a\x0a\x0a#\x20Remove\x20a\x20replace\x20directive.\x0a$\x20go\x20mod\x20edit\x20-dropreplace\x20example.com/a@v1.0.0\x0a\x0a#\x20Set\x20the\x20go\x20version,\x20add\x20a\x20requirement,\x20and\x20print\x20the\x20file\x0a#\x20instead\x20of\x20writing\x20it\x20to\x20disk.\x0a$\x20go\x20mod\x20edit\x20-go=1.14\x20-require=example.com/m@v1.0.0\x20-print\x0a\x0a#\x20Format\x20the\x20go.mod\x20file.\x0a$\x20go\x20mod\x20edit\x20-fmt\x0a\x0a#\x20Format\x20and\x20print\x20a\x20different\x20.mod\x20file.\x0a$\x20go\x20mod\x20edit\x20-print\x20tools.mod\x0a\x0a#\x20Print\x20a\x20JSON\x20representation\x20of\x20the\x20go.mod\x20file.\x0a$\x20go\x20mod\x20edit\x20-json\x0aThe\x20go\x20mod\x20edit\x20command\x20provides\x20a\x20command-line\x20interface\x20for\x20editing\x20and\x0aformatting\x20go.mod\x20files,\x20for\x20use\x20primarily\x20by\x20tools\x20and\x20scripts.\x20go\x20mod\x20edit\x0areads\x20only\x20one\x20go.mod\x20file;\x20it\x20does\x20not\x20look\x20up\x20information\x20about\x20other\x0amodules.\x20By\x20default,\x20go\x20mod\x20edit\x20reads\x20and\x20writes\x20the\x20go.mod\x20file\x20of\x20the\x0amain\x20module,\x20but\x20a\x20different\x20target\x20file\x20can\x20be\x20specified\x20after\x20the\x20editing\x0aflags.
The\x20editing\x20flags\x20specify\x20a\x20sequence\x20of\x20editing\x20operations.
\x0a-module\x20flag\x20changes\x20the\x20module's\x20path\x20(the\x20go.mod\x20file's\x20module\x0aline).-go=version\x20flag\x20sets\x20the\x20expected\x20Go\x20language\x20version.-require=path@version\x20and\x20-droprequire=path\x20flags\x20add\x20and\x20drop\x20a\x0arequirement\x20on\x20the\x20given\x20module\x20path\x20and\x20version.\x20Note\x20that\x20-require\x0aoverrides\x20any\x20existing\x20requirements\x20on\x20path.\x20These\x20flags\x20are\x20mainly\x20for\x0atools\x20that\x20understand\x20the\x20module\x20graph.\x20Users\x20should\x20prefer\x20go\x20get\x20path@version\x20or\x20go\x20get\x20path@none,\x20which\x20make\x20other\x20go.mod\x20adjustments\x20as\x0aneeded\x20to\x20satisfy\x20constraints\x20imposed\x20by\x20other\x20modules.\x20See\x20go\x20get.-exclude=path@version\x20and\x20-dropexclude=path@version\x20flags\x20add\x20and\x20drop\x0aan\x20exclusion\x20for\x20the\x20given\x20module\x20path\x20and\x20version.\x20Note\x20that\x0a-exclude=path@version\x20is\x20a\x20no-op\x20if\x20that\x20exclusion\x20already\x20exists.-replace=old[@v]=new[@v]\x20flag\x20adds\x20a\x20replacement\x20of\x20the\x20given\x20module\x0apath\x20and\x20version\x20pair.\x20If\x20the\x20@v\x20in\x20old@v\x20is\x20omitted,\x20a\x20replacement\x0awithout\x20a\x20version\x20on\x20the\x20left\x20side\x20is\x20added,\x20which\x20applies\x20to\x20all\x20versions\x20of\x0athe\x20old\x20module\x20path.\x20If\x20the\x20@v\x20in\x20new@v\x20is\x20omitted,\x20the\x20new\x20path\x20should\x20be\x0aa\x20local\x20module\x20root\x20directory,\x20not\x20a\x20module\x20path.\x20Note\x20that\x20-replace\x0aoverrides\x20any\x20redundant\x20replacements\x20for\x20old[@v],\x20so\x20omitting\x20@v\x20will\x20drop\x0areplacements\x20for\x20specific\x20versions.-dropreplace=old[@v]\x20flag\x20drops\x20a\x20replacement\x20of\x20the\x20given\x20module\x20path\x0aand\x20version\x20pair.\x20If\x20the\x20@v\x20is\x20provided,\x20a\x20replacement\x20with\x20the\x20given\x0aversion\x20is\x20dropped.\x20An\x20existing\x20replacement\x20without\x20a\x20version\x20on\x20the\x20left\x20side\x0amay\x20still\x20replace\x20the\x20module.\x20If\x20the\x20@v\x20is\x20omitted,\x20a\x20replacement\x20without\x20a\x0aversion\x20is\x20dropped.The\x20editing\x20flags\x20may\x20be\x20repeated.\x20The\x20changes\x20are\x20applied\x20in\x20the\x20order\x20given.
\x0ago\x20mod\x20edit\x20has\x20additional\x20flags\x20that\x20control\x20its\x20output.
-fmt\x20flag\x20reformats\x20the\x20go.mod\x20file\x20without\x20making\x20other\x20changes.\x0aThis\x20reformatting\x20is\x20also\x20implied\x20by\x20any\x20other\x20modifications\x20that\x20use\x20or\x0arewrite\x20the\x20go.mod\x20file.\x20The\x20only\x20time\x20this\x20flag\x20is\x20needed\x20is\x20if\x20no\x0aother\x20flags\x20are\x20specified,\x20as\x20in\x20go\x20mod\x20edit\x20-fmt.-print\x20flag\x20prints\x20the\x20final\x20go.mod\x20in\x20its\x20text\x20format\x20instead\x20of\x0awriting\x20it\x20back\x20to\x20disk.-json\x20flag\x20prints\x20the\x20final\x20go.mod\x20in\x20JSON\x20format\x20instead\x20of\x20writing\x0ait\x20back\x20to\x20disk\x20in\x20text\x20format.\x20The\x20JSON\x20output\x20corresponds\x20to\x20these\x20Go\x20types:type\x20Module\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Path\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Version\x20string\x0a}\x0a\x0atype\x20GoMod\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Module\x20\x20Module\x0a\x20\x20\x20\x20\x20\x20\x20\x20Go\x20\x20\x20\x20\x20\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Require\x20[]Require\x0a\x20\x20\x20\x20\x20\x20\x20\x20Exclude\x20[]Module\x0a\x20\x20\x20\x20\x20\x20\x20\x20Replace\x20[]Replace\x0a}\x0a\x0atype\x20Require\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Path\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Version\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Indirect\x20bool\x0a}\x0a\x0atype\x20Replace\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Old\x20Module\x0a\x20\x20\x20\x20\x20\x20\x20\x20New\x20Module\x0a}\x0aNote\x20that\x20this\x20only\x20describes\x20the\x20go.mod\x20file\x20itself,\x20not\x20other\x20modules\x0areferred\x20to\x20indirectly.\x20For\x20the\x20full\x20set\x20of\x20modules\x20available\x20to\x20a\x20build,\x0ause\x20go\x20list\x20-m\x20-json\x20all.\x20See\x20go\x20list\x20-m.
For\x20example,\x20a\x20tool\x20can\x20obtain\x20the\x20go.mod\x20file\x20as\x20a\x20data\x20structure\x20by\x0aparsing\x20the\x20output\x20of\x20go\x20mod\x20edit\x20-json\x20and\x20can\x20then\x20make\x20changes\x20by\x20invoking\x0ago\x20mod\x20edit\x20with\x20-require,\x20-exclude,\x20and\x20so\x20on.
Tools\x20may\x20also\x20use\x20the\x20package\x0agolang.org/x/mod/modfile\x0ato\x20parse,\x20edit,\x20and\x20format\x20go.mod\x20files.
go\x20mod\x20initUsage:
\x0ago\x20mod\x20init\x20[module-path]\x0aExample:
\x0ago\x20mod\x20init\x0ago\x20mod\x20init\x20example.com/m\x0aThe\x20go\x20mod\x20init\x20command\x20initializes\x20and\x20writes\x20a\x20new\x20go.mod\x20file\x20in\x20the\x0acurrent\x20directory,\x20in\x20effect\x20creating\x20a\x20new\x20module\x20rooted\x20at\x20the\x20current\x0adirectory.\x20The\x20go.mod\x20file\x20must\x20not\x20already\x20exist.
init\x20accepts\x20one\x20optional\x20argument,\x20the\x20init\x20will\x20attempt\x0ato\x20infer\x20the\x20module\x20path\x20using\x20import\x20comments\x20in\x20.go\x20files,\x20vendoring\x20tool\x0aconfiguration\x20files,\x20and\x20the\x20current\x20directory\x20(if\x20in\x20GOPATH).
If\x20a\x20configuration\x20file\x20for\x20a\x20vendoring\x20tool\x20is\x20present,\x20init\x20will\x20attempt\x20to\x0aimport\x20module\x20requirements\x20from\x20it.\x20init\x20supports\x20the\x20following\x20configuration\x0afiles.
GLOCKFILE\x20(Glock)Godeps/Godeps.json\x20(Godeps)Gopkg.lock\x20(dep)dependencies.tsv\x20(godeps)glide.lock\x20(glide)vendor.conf\x20(trash)vendor.yml\x20(govend)vendor/manifest\x20(gvt)vendor/vendor.json\x20(govendor)Vendoring\x20tool\x20configuration\x20files\x20can't\x20always\x20be\x20translated\x20with\x20perfect\x0afidelity.\x20For\x20example,\x20if\x20multiple\x20packages\x20within\x20the\x20same\x20repository\x20are\x0aimported\x20at\x20different\x20versions,\x20and\x20the\x20repository\x20only\x20contains\x20one\x20module,\x20the\x0aimported\x20go.mod\x20can\x20only\x20require\x20the\x20module\x20at\x20one\x20version.\x20You\x20may\x20wish\x20to\x0arun\x20go\x20list\x20-m\x20all\x20to\x20check\x20all\x20versions\x20in\x20the\x20go\x20mod\x20tidy\x20to\x20add\x20missing\x0arequirements\x20and\x20to\x20drop\x20unused\x20requirements.
go\x20mod\x20tidyUsage:
\x0ago\x20mod\x20tidy\x20[-v]\x0ago\x20mod\x20tidy\x20ensures\x20that\x20the\x20go.mod\x20file\x20matches\x20the\x20source\x20code\x20in\x20the\x0amodule.\x20It\x20adds\x20any\x20missing\x20module\x20requirements\x20necessary\x20to\x20build\x20the\x20current\x0amodule's\x20packages\x20and\x20dependencies,\x20and\x20it\x20removes\x20requirements\x20on\x20modules\x20that\x0adon't\x20provide\x20any\x20relevant\x20packages.\x20It\x20also\x20adds\x20any\x20missing\x20entries\x20to\x0ago.sum\x20and\x20removes\x20unnecessary\x20entries.
The\x20-v\x20flag\x20causes\x20go\x20mod\x20tidy\x20to\x20print\x20information\x20about\x20removed\x20modules\x0ato\x20standard\x20error.
go\x20mod\x20tidy\x20works\x20by\x20loading\x20all\x20of\x20the\x20packages\x20in\x20the\x20go\x20mod\x20tidy\x20acts\x20as\x20if\x20all\x20build\x20tags\x20are\x20enabled,\x20so\x20it\x20will\x0aconsider\x20platform-specific\x20source\x20files\x20and\x20files\x20that\x20require\x20custom\x20build\x0atags,\x20even\x20if\x20those\x20source\x20files\x20wouldn't\x20normally\x20be\x20built.\x20There\x20is\x20one\x0aexception:\x20the\x20ignore\x20build\x20tag\x20is\x20not\x20enabled,\x20so\x20a\x20file\x20with\x20the\x20build\x0aconstraint\x20//\x20+build\x20ignore\x20will\x20not\x20be\x20considered.\x20Note\x20that\x20go\x20mod\x20tidy\x0awill\x20not\x20consider\x20packages\x20in\x20the\x20main\x20module\x20in\x20directories\x20named\x20testdata\x20or\x0awith\x20names\x20that\x20start\x20with\x20.\x20or\x20_\x20unless\x20those\x20packages\x20are\x20explicitly\x0aimported\x20by\x20other\x20packages.
Once\x20go\x20mod\x20tidy\x20has\x20loaded\x20this\x20set\x20of\x20packages,\x20it\x20ensures\x20that\x20each\x20module\x0athat\x20provides\x20one\x20or\x20more\x20packages\x20either\x20has\x20a\x20require\x20directive\x20in\x20the\x20main\x0amodule's\x20go.mod\x20file\x20or\x20is\x20required\x20by\x20another\x20required\x20module.\x20\x20go\x20mod\x20tidy\x0awill\x20add\x20a\x20requirement\x20on\x20the\x20latest\x20version\x20on\x20each\x20missing\x20module\x20(see\x0alatest\x0aversion).\x20go\x20mod\x20tidy\x20will\x20remove\x20require\x20directives\x20for\x20modules\x20that\x20don't\x0aprovide\x20any\x20packages\x20in\x20the\x20set\x20described\x20above.
go\x20mod\x20tidy\x20may\x20also\x20add\x20or\x20remove\x20//\x20indirect\x20comments\x20on\x20require\x0adirectives.\x20An\x20//\x20indirect\x20comment\x20denotes\x20a\x20module\x20that\x20does\x20not\x20provide\x0apackages\x20imported\x20by\x20packages\x20in\x20the\x20main\x20module.\x20These\x20requirements\x20will\x20be\x0apresent\x20if\x20the\x20module\x20that\x20imports\x20packages\x20in\x20the\x20indirect\x20dependency\x20has\x0ano\x20go.mod\x20file.\x20They\x20may\x20also\x20be\x20present\x20if\x20the\x20indirect\x20dependency\x20is\x0arequired\x20at\x20a\x20higher\x20version\x20than\x20is\x20implied\x20by\x20the\x20module\x20graph;\x20this\x20usually\x0ahappens\x20after\x20running\x20a\x20command\x20like\x20go\x20get\x20-u\x20./....
go\x20mod\x20vendorUsage:
\x0ago\x20mod\x20vendor\x20[-v]\x0aThe\x20go\x20mod\x20vendor\x20command\x20constructs\x20a\x20directory\x20named\x20vendor\x20in\x20the\x20go\x20mod\x20tidy\x20and\x20other\x20module\x20commands,\x0aignore\x20are\x20not\x0aconsidered\x20when\x20constructing\x20the\x20vendor\x20directory.
When\x20vendoring\x20is\x20enabled,\x20the\x20go\x20command\x20will\x20load\x20packages\x20from\x20the\x20vendor\x0adirectory\x20instead\x20of\x20downloading\x20modules\x20from\x20their\x20sources\x20into\x20the\x20module\x0acache\x20and\x20using\x20packages\x20those\x20downloaded\x20copies.\x20See\x20
go\x20mod\x20vendor\x20also\x20creates\x20the\x20file\x20vendor/modules.txt\x20that\x20contains\x20a\x20list\x0aof\x20vendored\x20packages\x20and\x20the\x20module\x20versions\x20they\x20were\x20copied\x20from.\x20When\x0avendoring\x20is\x20enabled,\x20this\x20manifest\x20is\x20used\x20as\x20a\x20source\x20of\x20module\x20version\x0ainformation,\x20as\x20reported\x20by\x20go\x20list\x20-m\x20and\x20go\x20version\x20-m.\x20When\x20the\x20go\x20command\x20reads\x20vendor/modules.txt,\x20it\x20checks\x0athat\x20the\x20module\x20versions\x20are\x20consistent\x20with\x20go.mod.\x20If\x20go.mod\x20changed\x20since\x0avendor/modules.txt\x20was\x20generated,\x20go\x20mod\x20vendor\x20should\x20be\x20run\x20again.
Note\x20that\x20go\x20mod\x20vendor\x20removes\x20the\x20vendor\x20directory\x20if\x20it\x20exists\x20before\x0are-constructing\x20it.\x20Local\x20changes\x20should\x20not\x20be\x20made\x20to\x20vendored\x20packages.\x0aThe\x20go\x20command\x20does\x20not\x20check\x20that\x20packages\x20in\x20the\x20vendor\x20directory\x20have\x0anot\x20been\x20modified,\x20but\x20one\x20can\x20verify\x20the\x20integrity\x20of\x20the\x20vendor\x20directory\x0aby\x20running\x20go\x20mod\x20vendor\x20and\x20checking\x20that\x20no\x20changes\x20were\x20made.
The\x20-v\x20flag\x20causes\x20go\x20mod\x20vendor\x20to\x20print\x20the\x20names\x20of\x20vendored\x20modules\x0aand\x20packages\x20to\x20standard\x20error.
go\x20mod\x20verifygo\x20version\x20-mUsage:
\x0ago\x20version\x20[-m]\x20[-v]\x20[file\x20...]\x0aExample:
\x0a#\x20Print\x20Go\x20version\x20used\x20to\x20build\x20go.\x0a$\x20go\x20version\x0a\x0a#\x20Print\x20Go\x20version\x20used\x20to\x20build\x20a\x20specific\x20executable.\x0a$\x20go\x20version\x20~/go/bin/gopls\x0a\x0a#\x20Print\x20Go\x20version\x20and\x20module\x20versions\x20used\x20to\x20build\x20a\x20specific\x20executable.\x0a$\x20go\x20version\x20-m\x20~/go/bin/gopls\x0a\x0a#\x20Print\x20Go\x20version\x20and\x20module\x20versions\x20used\x20to\x20build\x20executables\x20in\x20a\x20directory.\x0a$\x20go\x20version\x20-m\x20~/go/bin/\x0ago\x20version\x20reports\x20the\x20Go\x20version\x20used\x20to\x20build\x20each\x20executable\x20file\x20named\x0aon\x20the\x20command\x20line.
If\x20no\x20files\x20are\x20named\x20on\x20the\x20command\x20line,\x20go\x20version\x20prints\x20its\x20own\x20version\x0ainformation.
If\x20a\x20directory\x20is\x20named,\x20go\x20version\x20walks\x20that\x20directory,\x20recursively,\x20looking\x0afor\x20recognized\x20Go\x20binaries\x20and\x20reporting\x20their\x20versions.\x20By\x20default,\x20go\x20version\x20does\x20not\x20report\x20unrecognized\x20files\x20found\x20during\x20a\x20directory\x20scan.\x20The\x0a-v\x20flag\x20causes\x20it\x20to\x20report\x20unrecognized\x20files.
The\x20-m\x20flag\x20causes\x20go\x20version\x20to\x20print\x20each\x20executable's\x20embedded\x20module\x0aversion\x20information,\x20when\x20available.\x20For\x20each\x20executable,\x20go\x20version\x20-m\x20prints\x0aa\x20table\x20with\x20tab-separated\x20columns\x20like\x20the\x20one\x20below.
$\x20go\x20version\x20-m\x20~/go/bin/goimports\x0a/home/jrgopher/go/bin/goimports:\x20go1.14.3\x0a\x20\x20\x20\x20\x20\x20\x20\x20path\x20\x20\x20\x20golang.org/x/tools/cmd/goimports\x0a\x20\x20\x20\x20\x20\x20\x20\x20mod\x20\x20\x20\x20\x20golang.org/x/tools\x20\x20\x20\x20\x20\x20v0.0.0-20200518203908-8018eb2c26ba\x20\x20\x20\x20\x20\x20h1:0Lcy64USfQQL6GAJma8BdHCgeofcchQj+Z7j0SXYAzU=\x0a\x20\x20\x20\x20\x20\x20\x20\x20dep\x20\x20\x20\x20\x20golang.org/x/mod\x20\x20\x20\x20\x20\x20\x20\x20v0.2.0\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20h1:KU7oHjnv3XNWfa5COkzUifxZmxp1TyI7ImMXqFxLwvQ=\x0a\x20\x20\x20\x20\x20\x20\x20\x20dep\x20\x20\x20\x20\x20golang.org/x/xerrors\x20\x20\x20\x20v0.0.0-20191204190536-9bdfabe68543\x20\x20\x20\x20\x20\x20h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=\x0aThe\x20format\x20of\x20the\x20table\x20may\x20change\x20in\x20the\x20future.\x20The\x20same\x20information\x20may\x20be\x0aobtained\x20from\x0aruntime/debug.ReadBuildInfo.
The\x20meaning\x20of\x20each\x20row\x20in\x20the\x20table\x20is\x20determined\x20by\x20the\x20word\x20in\x20the\x20first\x0acolumn.
\x0apath:\x20the\x20path\x20of\x20the\x20main\x20package\x20used\x20to\x20build\x20the\x20executable.mod:\x20the\x20module\x20containing\x20the\x20main\x20package.\x20The\x20columns\x20are\x20the\x0amodule\x20path,\x20version,\x20and\x20sum,\x20respectively.\x20The\x20(devel)\x20and\x20no\x20sum.dep:\x20a\x20module\x20that\x20provided\x20one\x20or\x20more\x20packages\x20linked\x20into\x20the\x0aexecutable.\x20Same\x20format\x20as\x20mod.=>:\x20a\x20mod\x20and\x20dep.\x20A\x20replaced\x20module\x20has\x0ano\x20sum.go\x20clean\x20-modcacheUsage:
\x0ago\x20clean\x20[-modcache]\x0aThe\x20-modcache\x20flag\x20causes\x20go\x20clean\x20to\x20remove\x20the\x20entire\x0a
This\x20is\x20usually\x20the\x20best\x20way\x20to\x20remove\x20the\x20module\x20cache.\x20By\x20default,\x20most\x20files\x0aand\x20directories\x20in\x20the\x20module\x20cache\x20are\x20read-only\x20to\x20prevent\x20tests\x20and\x20editors\x0afrom\x20unintentionally\x20changing\x20files\x20after\x20they've\x20been\x0arm\x20-r\x20to\x20fail,\x20since\x20files\x20can't\x20be\x20removed\x20without\x20first\x20making\x20their\x20parent\x0adirectories\x20writable.
The\x20-modcacherw\x20flag\x20(accepted\x20by\x20go\x20build\x20and\x0aother\x20module-aware\x20commands)\x20causes\x20new\x20directories\x20in\x20the\x20module\x20cache\x20to\x0abe\x20writable.\x20To\x20pass\x20-modcacherw\x20to\x20all\x20module-aware\x20commands,\x20add\x20it\x20to\x20the\x0aGOFLAGS\x20variable.\x20GOFLAGS\x20may\x20be\x20set\x20in\x20the\x20environment\x20or\x20with\x20go\x20env\x20-w.\x20For\x0aexample,\x20the\x20command\x20below\x20sets\x20it\x20permanently:
go\x20env\x20-w\x20GOFLAGS=-modcacherw\x0a-modcacherw\x20should\x20be\x20used\x20with\x20caution;\x20developers\x20should\x20be\x20careful\x20not\x0ato\x20make\x20changes\x20to\x20files\x20in\x20the\x20module\x20cache.\x20go\x20mod\x20verify\x0amay\x20be\x20used\x20to\x20check\x20that\x20files\x20in\x20the\x20cache\x20match\x20hashes\x20in\x20the\x20main\x20module's\x0ago.sum\x20file.
Several\x20commands\x20allow\x20you\x20to\x20specify\x20a\x20version\x20of\x20a\x20module\x20using\x20a\x20version\x0aquery,\x20which\x20appears\x20after\x20an\x20@\x20character\x20following\x20a\x20module\x20or\x20package\x20path\x0aon\x20the\x20command\x20line.
Examples:
\x0ago\x20get\x20example.com/m@latest\x0ago\x20mod\x20download\x20example.com/m@master\x0ago\x20list\x20-m\x20-json\x20example.com/m@e3702bed2\x0aA\x20version\x20query\x20may\x20be\x20one\x20of\x20the\x20following:
\x0av1.2.3,\x20which\x20selects\x20a\x0aspecific\x20version.\x20See\x20v1\x20or\x20v1.2,\x20which\x20selects\x20the\x20highest\x0aavailable\x20version\x20with\x20that\x20prefix.<v1.2.3\x20or\x20>=v1.5.6,\x20which\x20selects\x0athe\x20nearest\x20available\x20version\x20to\x20the\x20comparison\x20target\x20(the\x20lowest\x20version\x0afor\x20>\x20and\x20>=,\x20and\x20the\x20highest\x20version\x20for\x20<\x20and\x20<=).v2\x20selects\x20the\x0alatest\x20version\x20starting\x20with\x20v2,\x20not\x20the\x20branch\x20named\x20v2.latest,\x20which\x20selects\x20the\x20highest\x20available\x20release\x20version.\x20If\x0athere\x20are\x20no\x20release\x20versions,\x20latest\x20selects\x20the\x20highest\x20pre-release\x0aversion.\x20\x20If\x20there\x20no\x20tagged\x20versions,\x20latest\x20selects\x20a\x20pseudo-version\x20for\x0athe\x20commit\x20at\x20the\x20tip\x20of\x20the\x20repository's\x20default\x20branch.upgrade,\x20which\x20is\x20like\x20latest\x20except\x20that\x20if\x20the\x20module\x20is\x0acurrently\x20required\x20at\x20a\x20higher\x20version\x20than\x20the\x20version\x20latest\x20would\x20select\x0a(for\x20example,\x20a\x20pre-release),\x20upgrade\x20will\x20select\x20the\x20current\x20version.patch,\x20which\x20selects\x20the\x20latest\x20available\x20version\x20with\x20the\x20same\x0amajor\x20and\x20minor\x20version\x20numbers\x20as\x20the\x20currently\x20required\x20version.\x20If\x20no\x0aversion\x20is\x20currently\x20required,\x20patch\x20is\x20equivalent\x20to\x20latest.Except\x20for\x20queries\x20for\x20specific\x20named\x20versions\x20or\x20revisions,\x20all\x20queries\x0aconsider\x20available\x20versions\x20reported\x20by\x20go\x20list\x20-m\x20-versions\x20(see\x20go\x20list\x20-m).\x20This\x20list\x20contains\x20only\x20tagged\x20versions,\x20not\x20pseudo-versions.\x0aModule\x20versions\x20disallowed\x20by\x20go.mod\x20file\x20are\x20not\x20considered.
v1.2.2\x20and\x20v1.2.3-pre\x20are\x20available,\x20the\x0alatest\x20query\x20will\x20select\x20v1.2.2,\x20even\x20though\x20v1.2.3-pre\x20is\x20higher.\x20The\x0a<v1.2.4\x20query\x20would\x20also\x20select\x20v1.2.2,\x20even\x20though\x20v1.2.3-pre\x20is\x20closer\x0ato\x20v1.2.4.\x20If\x20no\x20release\x20or\x20pre-release\x20version\x20is\x20available,\x20the\x20latest,\x0aupgrade,\x20and\x20patch\x20queries\x20will\x20select\x20a\x20pseudo-version\x20for\x20the\x20commit\x0aat\x20the\x20tip\x20of\x20the\x20repository's\x20default\x20branch.\x20Other\x20queries\x20will\x20report\x0aan\x20error.
Module-aware\x20Go\x20commands\x20normally\x20run\x20in\x20the\x20context\x20of\x20a\x20go.mod\x20file\x20in\x20the\x20working\x20directory\x0aor\x20a\x20parent\x20directory.\x20Some\x20commands\x20may\x20be\x20run\x20in\x20module-aware\x20mode\x20without\x20a\x0ago.mod\x20file\x20by\x20setting\x20the\x20GO111MODULE\x20environment\x20variable\x20to\x20on.\x0aMost\x20commands\x20work\x20differently\x20when\x20no\x20go.mod\x20file\x20is\x20present.
See\x20
go\x20buildgo\x20docgo\x20fixgo\x20fmtgo\x20generatego\x20installgo\x20listgo\x20rungo\x20testgo\x20vet\x0a\x20\x20\x20\x20\x20\x20.go\x20files\x20on\x20the\x20command\x20line\x20can\x20be\x20loaded,\x20imported,\x20and\x0a\x20\x20\x20\x20\x20\x20\x20\x20built.\x20Packages\x20from\x20other\x20modules\x20cannot\x20be\x20built,\x20since\x20there\x20is\x20no\x0a\x20\x20\x20\x20\x20\x20\x20\x20place\x20to\x20record\x20module\x20requirements\x20and\x20ensure\x20deterministic\x20builds.\x0a\x20\x20\x20\x20\x20\x20go\x20getgo\x20get\x20is\x20run\x20without\x20a\x0a\x20\x20\x20\x20\x20\x20\x20\x20go.mod\x20file,\x20so\x20replace\x20and\x0a\x20\x20\x20\x20\x20\x20\x20\x20exclude\x20directives\x20are\x20not\x20applied.\x0a\x20\x20\x20\x20\x20\x20go\x20list\x20-m-versions\x20flag\x20is\x20used.\x0a\x20\x20\x20\x20\x20\x20go\x20mod\x20downloadgo\x20mod\x20editgo\x20mod\x20graphgo\x20mod\x20tidygo\x20mod\x20vendorgo\x20mod\x20verifygo\x20mod\x20why\x0a\x20\x20\x20\x20\x20\x20go.mod\x20file\x20and\x20will\x20report\x0a\x20\x20\x20\x20\x20\x20\x20\x20an\x20error\x20if\x20one\x20is\x20not\x20present.\x0a\x20\x20\x20\x20\x20\x20GOPROXY\x20protocolA\x20GET\x20requests\x20for\x20paths\x20specified\x20below.\x20The\x20requests\x20have\x20no\x20query\x20parameters,\x0aand\x20no\x20specific\x20headers\x20are\x20required,\x20so\x20even\x20a\x20site\x20serving\x20from\x20a\x20fixed\x20file\x0asystem\x20(including\x20a\x20file://\x20URL)\x20can\x20be\x20a\x20module\x20proxy.
Successful\x20HTTP\x20responses\x20must\x20have\x20the\x20status\x20code\x20200\x20(OK).\x20Redirects\x20(3xx)\x0aare\x20followed.\x20Responses\x20with\x20status\x20codes\x204xx\x20and\x205xx\x20are\x20treated\x20as\x20errors.\x0aThe\x20error\x20codes\x20404\x20(Not\x20Found)\x20and\x20410\x20(Gone)\x20indicate\x20that\x20the\x0arequested\x20module\x20or\x20version\x20is\x20not\x20available\x20on\x20the\x20proxy,\x20but\x20it\x20may\x20be\x20found\x0aelsewhere.\x20Error\x20responses\x20should\x20have\x20content\x20type\x20text/plain\x20with\x0acharset\x20either\x20utf-8\x20or\x20us-ascii.
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The\x20table\x20below\x20specifies\x20queries\x20that\x20a\x20module\x20proxy\x20must\x20respond\x20to.\x20For\x20each\x0apath,\x20$base\x20is\x20the\x20path\x20portion\x20of\x20a\x20proxy\x20URL,$module\x20is\x20a\x20module\x20path,\x20and\x0a$version\x20is\x20a\x20version.\x20For\x20example,\x20if\x20the\x20proxy\x20URL\x20is\x0ahttps://example.com/mod,\x20and\x20the\x20client\x20is\x20requesting\x20the\x20go.mod\x20file\x20for\x0athe\x20module\x20golang.org/x/text\x20at\x20version\x20v0.3.2,\x20the\x20client\x20would\x20send\x20a\x0aGET\x20request\x20for\x20https://example.com/mod/golang.org/x/text/@v/v0.3.2.mod.
To\x20avoid\x20ambiguity\x20when\x20serving\x20from\x20case-insensitive\x20file\x20systems,\x0athe\x20$module\x20and\x20$version\x20elements\x20are\x20case-encoded\x20by\x20replacing\x20every\x0auppercase\x20letter\x20with\x20an\x20exclamation\x20mark\x20followed\x20by\x20the\x20corresponding\x0alower-case\x20letter.\x20This\x20allows\x20modules\x20example.com/M\x20and\x20example.com/m\x20to\x0aboth\x20be\x20stored\x20on\x20disk,\x20since\x20the\x20former\x20is\x20encoded\x20as\x20example.com/!m.
$base/$module/@v/list$base/$module/@v/$version.info\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Returns\x20JSON-formatted\x20metadata\x20about\x20a\x20specific\x20version\x20of\x20a\x20module.\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20The\x20response\x20must\x20be\x20a\x20JSON\x20object\x20that\x20corresponds\x20to\x20the\x20Go\x20data\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20structure\x20below:\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x0atype\x20Info\x20struct\x20{\x0a\x20\x20\x20\x20Version\x20string\x20\x20\x20\x20//\x20version\x20string\x0a\x20\x20\x20\x20Time\x20\x20\x20\x20time.Time\x20//\x20commit\x20time\x0a}\x0a\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20The\x20Version\x20field\x20is\x20required\x20and\x20must\x20contain\x20a\x20valid,\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20$version\x20in\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20request\x20path\x20does\x20not\x20need\x20to\x20be\x20the\x20same\x20version\x20or\x20even\x20a\x20valid\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20version;\x20this\x20endpoint\x20may\x20be\x20used\x20to\x20find\x20versions\x20for\x20branch\x20names\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20or\x20revision\x20identifiers.\x20However,\x20if\x20$version\x20is\x20a\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20canonical\x20version\x20with\x20a\x20major\x20version\x20compatible\x20with\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20$module,\x20the\x20Version\x20field\x20in\x20a\x20successful\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20response\x20must\x20be\x20the\x20same.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20The\x20Time\x20field\x20is\x20optional.\x20If\x20present,\x20it\x20must\x20be\x20a\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20string\x20in\x20RFC\x203339\x20format.\x20It\x20indicates\x20the\x20time\x20when\x20the\x20version\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20was\x20created.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20More\x20fields\x20may\x20be\x20added\x20in\x20the\x20future,\x20so\x20other\x20names\x20are\x20reserved.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20$base/$module/@v/$version.modgo.mod\x20file\x20for\x20a\x20specific\x20version\x20of\x20a\x0a\x20\x20\x20\x20\x20\x20\x20\x20module.\x20If\x20the\x20module\x20does\x20not\x20have\x20a\x20go.mod\x20file\x20at\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20requested\x20version,\x20a\x20file\x20containing\x20only\x20a\x20module\x0a\x20\x20\x20\x20\x20\x20\x20\x20statement\x20with\x20the\x20requested\x20module\x20path\x20must\x20be\x20returned.\x20Otherwise,\x0a\x20\x20\x20\x20\x20\x20\x20\x20the\x20original,\x20unmodified\x20go.mod\x20file\x20must\x20be\x20returned.\x0a\x20\x20\x20\x20\x20\x20$base/$module/@v/$version.zip$base/$module/@latest$base/$module/@v/$version.info.\x20The\x20latest\x20version\x20should\x0a\x20\x20\x20\x20\x20\x20\x20\x20be\x20the\x20version\x20of\x20the\x20module\x20that\x20the\x20go\x20command\x20should\x20use\x0a\x20\x20\x20\x20\x20\x20\x20\x20if\x20$base/$module/@v/list\x20is\x20empty\x20or\x20no\x20listed\x20version\x20is\x0a\x20\x20\x20\x20\x20\x20\x20\x20suitable.\x20This\x20endpoint\x20is\x20optional,\x20and\x20module\x20proxies\x20are\x20not\x20required\x0a\x20\x20\x20\x20\x20\x20\x20\x20to\x20implement\x20it.\x0a\x20\x20\x20\x20\x20\x20When\x20resolving\x20the\x20latest\x20version\x20of\x20a\x20module,\x20the\x20go\x20command\x20will\x20request\x0a$base/$module/@v/list,\x20then,\x20if\x20no\x20suitable\x20versions\x20are\x20found,\x0a$base/$module/@latest.\x20The\x20go\x20command\x20prefers,\x20in\x20order:\x20the\x20semantically\x0ahighest\x20release\x20version,\x20the\x20semantically\x20highest\x20pre-release\x20version,\x20and\x20the\x0achronologically\x20most\x20recent\x20pseudo-version.\x20In\x20Go\x201.12\x20and\x20earlier,\x20the\x20go\x0acommand\x20considered\x20pseudo-versions\x20in\x20$base/$module/@v/list\x20to\x20be\x20pre-release\x0aversions,\x20but\x20this\x20is\x20no\x20longer\x20true\x20since\x20Go\x201.13.
A\x20module\x20proxy\x20must\x20always\x20serve\x20the\x20same\x20content\x20for\x20successful\x0aresponses\x20for\x20$base/$module/$version.mod\x20and\x20$base/$module/$version.zip\x0aqueries.\x20This\x20content\x20is\x20go.sum\x20files\x20and,\x20by\x20default,\x20the\x0a
The\x20go\x20command\x20caches\x20most\x20content\x20it\x20downloads\x20from\x20module\x20proxies\x20in\x20its\x0amodule\x20cache\x20in\x20$GOPATH/pkg/mod/cache/download.\x20Even\x20when\x20downloading\x20directly\x0afrom\x20version\x20control\x20systems,\x20the\x20go\x20command\x20synthesizes\x20explicit\x20info,\x0amod,\x20and\x20zip\x20files\x20and\x20stores\x20them\x20in\x20this\x20directory,\x20the\x20same\x20as\x20if\x20it\x20had\x0adownloaded\x20them\x20directly\x20from\x20a\x20proxy.\x20The\x20cache\x20layout\x20is\x20the\x20same\x20as\x20the\x20proxy\x0aURL\x20space,\x20so\x20serving\x20$GOPATH/pkg/mod/cache/download\x20at\x20(or\x20copying\x20it\x20to)\x0ahttps://example.com/proxy\x20would\x20let\x20users\x20access\x20cached\x20module\x20versions\x20by\x0asetting\x20GOPROXY\x20to\x20https://example.com/proxy.
The\x20go\x20command\x20may\x20download\x20module\x20source\x20code\x20and\x20metadata\x20from\x20a\x20GOPROXY\x20go\x20command\x20may\x20connect\x20to\x20and\x20whether\x20it\x20may\x20communicate\x20directly\x20with\x0ago\x20command\x20will\x20only\x20contact\x20a\x20proxy\x20when\x20it\x0aneeds\x20information\x20not\x20already\x20in\x20the\x20cache.
The\x20GOPROXY\x20protocol\x20section\x20describes\x20requests\x20that\x0amay\x20be\x20sent\x20to\x20a\x20GOPROXY\x20server.\x20However,\x20it's\x20also\x20helpful\x20to\x20understand\x0awhen\x20the\x20go\x20command\x20makes\x20these\x20requests.\x20For\x20example,\x20go\x20build\x20follows\x0athe\x20procedure\x20below:
go.mod\x0afiles\x20and\x20performing\x20go.mod,\x0aand\x20start\x20over.When\x20the\x20go\x20command\x20computes\x20the\x20build\x20list,\x20it\x20loads\x20the\x20go.mod\x20file\x20for\x0aeach\x20module\x20in\x20the\x20go.mod\x20file\x20is\x20not\x0ain\x20the\x20cache,\x20the\x20go\x20command\x20will\x20download\x20it\x20from\x20the\x20proxy\x20using\x20a\x0a$module/@v/$version.mod\x20request\x20(where\x20$module\x20is\x20the\x20module\x20path\x20and\x0a$version\x20is\x20the\x20version).\x20These\x20requests\x20can\x20be\x20tested\x20with\x20a\x20tool\x20like\x0acurl.\x20For\x20example,\x20the\x20command\x20below\x20downloads\x20the\x20go.mod\x20file\x20for\x0agolang.org/x/mod\x20at\x20version\x20v0.2.0:
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The\x20major\x20version\x20number\x20of\x20a\x20semantic\x20version\x20tag\x20must\x20be\x20consistent\x20with\x20the\x0amodule\x20path's\x20major\x20version\x20suffix\x20(if\x20any).\x20For\x20example,\x20the\x20tag\x20v1.0.0\x20could\x0abelong\x20to\x20the\x20module\x20example.com/mod\x20but\x20not\x20example.com/mod/v2,\x20which\x20would\x0ahave\x20tags\x20like\x20v2.0.0.
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See\x20
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go\x20get\x20example.com/mod@master\x0aThe\x20go\x20command\x20converts\x20these\x20names\x20into\x20
If\x20a\x20revision\x20is\x20tagged\x20with\x20one\x20or\x20more\x20semantic\x20version\x20tags\x20like\x20v1.2.3,\x0athe\x20tag\x20for\x20the\x20highest\x20valid\x20version\x20will\x20be\x20used.\x20The\x20go\x20command\x20only\x0aconsiders\x20semantic\x20version\x20tags\x20that\x20could\x20belong\x20to\x20the\x20target\x20module;\x20for\x0aexample,\x20the\x20tag\x20v1.5.2\x20would\x20not\x20be\x20considered\x20for\x20example.com/mod/v2\x20since\x0athe\x20major\x20version\x20doesn't\x20match\x20the\x20module\x20path's\x20suffix.
If\x20a\x20revision\x20is\x20not\x20tagged\x20with\x20a\x20valid\x20semantic\x20version\x20tag,\x20the\x20go\x20command\x0awill\x20generate\x20a\x20
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GONOPROXY\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Comma-separated\x20list\x20of\x20glob\x20patterns\x20(in\x20the\x20syntax\x20of\x20Go's\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20path.Match)\x20of\x20module\x20path\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20prefixes\x20that\x20should\x20always\x20be\x20fetched\x20directly\x20from\x20version\x20control\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20repositories,\x20not\x20from\x20module\x20proxies.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20GONOPROXY\x20is\x20not\x20set,\x20it\x20defaults\x20to\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE.\x20See\x20
GONOSUMDB\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Comma-separated\x20list\x20of\x20glob\x20patterns\x20(in\x20the\x20syntax\x20of\x20Go's\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20path.Match)\x20of\x20module\x20path\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20prefixes\x20for\x20which\x20the\x20go\x20should\x20not\x20verify\x20checksums\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20using\x20the\x20checksum\x20database.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20GONOSUMDB\x20is\x20not\x20set,\x20it\x20defaults\x20to\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE.\x20See\x20
GOPATH\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20In\x20GOPATH\x20mode,\x20the\x20GOPATH\x20variable\x20is\x20a\x20list\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20of\x20directories\x20that\x20may\x20contain\x20Go\x20code.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
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\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20GOPATH\x20is\x20not\x20set,\x20it\x20defaults\x20to\x20the\x20go\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20subdirectory\x20of\x20the\x20user's\x20home\x20directory.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
GOPRIVATEpath.Match)\x20of\x20module\x20path\x0a\x20\x20\x20\x20\x20\x20\x20\x20prefixes\x20that\x20should\x20be\x20considered\x20private.\x20GOPRIVATE\x0a\x20\x20\x20\x20\x20\x20\x20\x20is\x20a\x20default\x20value\x20for\x20GONOPROXY\x20and\x0a\x20\x20\x20\x20\x20\x20\x20\x20GONOSUMDB.\x20GOPRIVATE\x20itself\x20has\x20no\x20other\x0a\x20\x20\x20\x20\x20\x20\x20\x20meaning.\x20See\x20GOPROXY\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Comma-separated\x20list\x20of\x20module\x20proxy\x20URLs.\x20When\x20the\x20go\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20command\x20looks\x20up\x20information\x20about\x20a\x20module,\x20it\x20will\x20contact\x20each\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20proxy\x20in\x20the\x20list,\x20in\x20sequence.\x20A\x20proxy\x20may\x20respond\x20with\x20a\x20404\x20(Not\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Found)\x20or\x20410\x20(Gone)\x20status\x20to\x20indicate\x20the\x20module\x20is\x20not\x20available\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20and\x20the\x20go\x20command\x20should\x20contact\x20the\x20next\x20proxy\x20in\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20list.\x20Any\x20other\x20error\x20will\x20cause\x20the\x20go\x20command\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20to\x20stop\x20without\x20contacting\x20other\x20proxies\x20in\x20the\x20list.\x20This\x20allows\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20a\x20proxy\x20to\x20act\x20as\x20a\x20gatekeeper,\x20for\x20example,\x20by\x20responding\x20with\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20403\x20(Forbidden)\x20for\x20modules\x20not\x20on\x20an\x20approved\x20list.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPROXY\x20URLs\x20may\x20have\x20the\x20schemes\x20https,\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20http,\x20or\x20file.\x20If\x20no\x20scheme\x20is\x20specified,\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20https\x20is\x20assumed.\x20A\x20module\x20cache\x20may\x20be\x20used\x20direclty\x20as\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20a\x20file\x20proxy:\x0a\x20\x20\x20\x20\x20\x20\x20\x20
GOPROXY=file://$(go\x20env\x20GOPATH)/pkg/mod/cache/download\x0a\x20\x20\x20\x20\x20\x20\x20\x20
Two\x20keywords\x20may\x20be\x20used\x20in\x20place\x20of\x20proxy\x20URLs:
\x0a\x20\x20\x20\x20\x20\x20\x20\x20off:\x20disallows\x20downloading\x20modules\x20from\x20any\x20source.\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20direct:\x20download\x20directly\x20from\x20version\x20control\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20repositories.\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPROXY\x20defaults\x20to\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20https://proxy.golang.org,direct.\x20Under\x20that\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20configuration,\x20the\x20go\x20command\x20will\x20first\x20contact\x20the\x20Go\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20module\x20mirror\x20run\x20by\x20Google,\x20then\x20fall\x20back\x20to\x20a\x20direct\x20connection\x20if\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20mirror\x20does\x20not\x20have\x20the\x20module.\x20See\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE\x20and\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GONOPROXY\x20environment\x20variables\x20may\x20be\x20set\x20to\x20prevent\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20specific\x20modules\x20from\x20being\x20downloaded\x20using\x20proxies.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20See\x20
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\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x0aGOSUMDB=\"sum.golang.org\"\x0aGOSUMDB=\"sum.golang.org+<publickey>\"\x0aGOSUMDB=\"sum.golang.org+<publickey>\x20https://sum.golang.org\x0a\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20The\x20go\x20command\x20knows\x20the\x20public\x20key\x20of\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20sum.golang.org\x20and\x20also\x20that\x20the\x20name\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20sum.golang.google.cn\x20(available\x20inside\x20mainland\x20China)\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20connects\x20to\x20the\x20sum.golang.org\x20database;\x20use\x20of\x20any\x20other\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20database\x20requires\x20giving\x20the\x20public\x20key\x20explicitly.\x20The\x20URL\x20defaults\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20to\x20https://\x20followed\x20by\x20the\x20database\x20name.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20 \x0a\x20\x20\x20\x20\x20\x20\x20\x20 \x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20 \x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20See\x20GOSUMDB\x20defaults\x20to\x20sum.golang.org,\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Go\x20checksum\x20database\x20run\x20by\x20Google.\x20See\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOSUMDB\x20is\x20set\x20to\x20off\x20or\x20if\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20go\x20get\x20is\x20invoked\x20with\x20the\x20-insecure\x20flag,\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20checksum\x20database\x20is\x20not\x20consulted,\x20and\x20all\x20unrecognized\x20modules\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20are\x20accepted,\x20at\x20the\x20cost\x20of\x20giving\x20up\x20the\x20security\x20guarantee\x20of\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20verified\x20repeatable\x20downloads\x20for\x20all\x20modules.\x20A\x20better\x20way\x20to\x20bypass\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20checksum\x20database\x20for\x20specific\x20modules\x20is\x20to\x20use\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE\x20or\x20GONOSUMDB\x20environment\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20variables.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
foo_linux_amd64.go)\x20or\x20with\x20build\x20constraint\x20comments\x0a(for\x20example,\x20//\x20+build\x20linux,amd64).\x20See\x20
go\x20build,\x20go\x20list,\x20or\x20go\x20test.\x20The\x20build\x20list\x20is\x0adetermined\x20from\x20the\x20go.mod\x0afile\x20and\x20go.mod\x20files\x20in\x20transitively\x20required\x20modules\x0ausing\x20
+incompatible.\x20For\x20example,\x20v1.2.3\x0ais\x20a\x20canonical\x20version,\x20but\x20v1.2.3+meta\x20is\x20not.
go.mod\x20file:\x20The\x20file\x20that\x20defines\x20a\x20module's\x20path,\x20requirements,\x20and\x0aother\x20metadata.\x20Appears\x20in\x20the\x20go.mod\x0afiles.
go\x20command\x20is\x20invoked.
1\x20in\x20v1.2.3).\x20In\x0aa\x20release\x20with\x20incompatible\x20changes,\x20the\x20major\x20version\x20must\x20be\x20incremented,\x20and\x0athe\x20minor\x20and\x20patch\x20versions\x20must\x20be\x20set\x20to\x200.\x20Semantic\x20versions\x20with\x20major\x0aversion\x200\x20are\x20considered\x20unstable.
example.com/mod/v2\x20in\x20the\x20repository\x20with\x20example.com/mod\x20may\x20be\x20defined\x20in\x20the\x0arepository\x20root\x20directory\x20or\x20the\x20major\x20version\x20subdirectory\x20v2.\x20See\x20
/v2\x20in\x20example.com/mod/v2.\x20Major\x20version\x20suffixes\x20are\x0arequired\x20at\x20v2.0.0\x20and\x20later\x20and\x20are\x20not\x20allowed\x20at\x20earlier\x20versions.\x20See\x0athe\x20section\x20on\x20
2\x20in\x20v1.2.3).\x20In\x0aa\x20release\x20with\x20new,\x20backwards\x20compatible\x20functionality,\x20the\x20minor\x20version\x20must\x0abe\x20incremented,\x20and\x20the\x20patch\x20version\x20must\x20be\x20set\x20to\x200.
GOPATH/pkg/mod.\x20See\x20
require\x20statement\x20in\x20a\x20go.mod\x20file\x20(subject\x20to\x20replace\x20and\x0aexclude\x20statements\x20in\x20the\x20main\x20module's\x20go.mod\x20file.
"golang.org/x/net".
GOPROXY\x0aprotocol.\x20The\x20go\x20command\x20downloads\x20version\x20information,\x0ago.mod\x20files,\x20and\x20module\x20zip\x20files\x20from\x20module\x20proxies.
go.mod\x20file\x20that\x0adefines\x20a\x20module.
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3\x20in\x20v1.2.3).\x20In\x0aa\x20release\x20with\x20no\x20changes\x20to\x20the\x20module's\x20public\x20interface,\x20the\x20patch\x20version\x0amust\x20be\x20incremented.
v1.2.3-beta4.\x20Pre-release\x20versions\x20are\x20considered\x20unstable\x20and\x20are\x20not\x0aassumed\x20to\x20be\x20compatible\x20with\x20other\x20versions.\x20A\x20pre-release\x20version\x20sorts\x20before\x0athe\x20corresponding\x20release\x20version:\x20v1.2.3-pre\x20comes\x20before\x20v1.2.3.\x20See\x20also\x0a
v0.0.0-20191109021931-daa7c04131f5.\x20Used\x20for\x20
v1.2.3,\x20not\x20v1.2.3-pre.\x20See\x20also\x20
v\x20followed\x20by\x20a\x20semantic\x20version.\x20See\x20the\x20section\x20on\x0a
A\x20go.mod\x0afile,\x20together\x20with\x20information\x20about\x20the\x20module's\x0adependencies.\x20The\x20go.mod\x20file.\x20The\x20go\x20command\x20is\x20invoked.
Each\x20"golang.org/x/net"\x20contains\x20a\x20package\x20in\x20the\x20directory\x20"html".\x20That\x0apackage's\x20path\x20is\x20"golang.org/x/net/html".
A\x20module\x20directive\x20in\x20the\x20module's\x0ago.mod\x20file.\x20A\x20module's\x20path\x20is\x20the\x20prefix\x20for\x20package\x0apaths\x20within\x20the\x20module.
A\x20module\x20path\x20should\x20describe\x20both\x20what\x20the\x20module\x20does\x20and\x20where\x20to\x20find\x20it.\x0aTypically,\x20a\x20module\x20path\x20consists\x20of\x20a\x20repository\x20root\x20path,\x20a\x20directory\x20within\x0athe\x20repository\x20(usually\x20empty),\x20and\x20a\x20major\x20version\x20suffix\x20(only\x20for\x20major\x0aversion\x202\x20or\x20higher).
\x0agolang.org/x/net\x20is\x20the\x20repository\x20root\x20path\x20for\x20the\x20module\x20of\x20the\x20same\x0aname.\x20See\x20go\x20command\x20locates\x20a\x20repository\x20using\x20HTTP\x20requests\x20derived\x0afrom\x20a\x20module\x20path.golang.org/x/tools/gopls\x20is\x20in\x20the\x20gopls\x20subdirectory\x20of\x20the\x20repository\x0awith\x20root\x20path\x20golang.org/x/tools,\x20so\x20it\x20has\x20the\x20module\x20subdirectory\x0agopls.\x20See\x20/v2.\x20This\x20may\x20or\x20may\x20not\x20be\x20part\x20of\x20the\x20subdirectory\x20name.\x20For\x20example,\x20the\x0amodule\x20with\x20path\x20golang.org/x/repo/sub/v2\x20could\x20be\x20in\x20the\x20/sub\x20or\x0a/sub/v2\x20subdirectory\x20of\x20the\x20repository\x20golang.org/x/repo.If\x20a\x20module\x20might\x20be\x20depended\x20on\x20by\x20other\x20modules,\x20these\x20rules\x20must\x20be\x20followed\x0aso\x20that\x20the\x20go\x20command\x20can\x20find\x20and\x20download\x20the\x20module.\x20There\x20are\x20also\x0aseveral\x20
A\x20v,\x20followed\x20by\x20a\x20semantic\x20version.\x20See\x20
To\x20summarize,\x20a\x20semantic\x20version\x20consists\x20of\x20three\x20non-negative\x20integers\x20(the\x0amajor,\x20minor,\x20and\x20patch\x20versions,\x20from\x20left\x20to\x20right)\x20separated\x20by\x20dots.\x20The\x0apatch\x20version\x20may\x20be\x20followed\x20by\x20an\x20optional\x20pre-release\x20string\x20starting\x20with\x20a\x0ahyphen.\x20The\x20pre-release\x20string\x20or\x20patch\x20version\x20may\x20be\x20followed\x20by\x20a\x20build\x0ametadata\x20string\x20starting\x20with\x20a\x20plus.\x20For\x20example,\x20v0.0.0,\x20v1.12.134,\x0av8.0.5-pre,\x20and\x20v2.0.9+meta\x20are\x20valid\x20versions.
Each\x20part\x20of\x20a\x20version\x20indicates\x20whether\x20the\x20version\x20is\x20stable\x20and\x20whether\x20it\x20is\x0acompatible\x20with\x20previous\x20versions.
\x0av1.2.3-pre\x20comes\x20before\x0av1.2.3.go.mod\x20files.\x20The\x0asuffix\x20+incompatible\x20denotes\x20a\x20version\x20released\x20before\x20migrating\x20to\x20modules\x0aversion\x20major\x20version\x202\x20or\x20later\x20(see\x20A\x20version\x20is\x20considered\x20unstable\x20if\x20its\x20major\x20version\x20is\x200\x20or\x20it\x20has\x20a\x0apre-release\x20suffix.\x20Unstable\x20versions\x20are\x20not\x20subject\x20to\x20compatibility\x0arequirements.\x20For\x20example,\x20v0.2.0\x20may\x20not\x20be\x20compatible\x20with\x20v0.1.0,\x20and\x0av1.5.0-beta\x20may\x20not\x20be\x20compatible\x20with\x20v1.5.0.
Go\x20may\x20access\x20modules\x20in\x20version\x20control\x20systems\x20using\x20tags,\x20branches,\x20or\x0arevisions\x20that\x20don't\x20follow\x20these\x20conventions.\x20However,\x20within\x20the\x20main\x20module,\x0athe\x20go\x20command\x20will\x20automatically\x20convert\x20revision\x20names\x20that\x20don't\x20follow\x0athis\x20standard\x20into\x20canonical\x20versions.\x20The\x20go\x20command\x20will\x20also\x20remove\x20build\x0ametadata\x20suffixes\x20(except\x20for\x20+incompatible)\x20as\x20part\x20of\x20this\x20process.\x20This\x20may\x0aresult\x20in\x20a\x20go\x20get\x20-d\x20golang.org/x/net@daa7c041\x20will\x20convert\x20the\x20commit\x20hash\x20daa7c041\x20into\x20the\x0apseudo-version\x20v0.0.0-20191109021931-daa7c04131f5.\x20Canonical\x20versions\x20are\x0arequired\x20outside\x20the\x20main\x20module,\x20and\x20the\x20go\x20command\x20will\x20report\x20an\x20error\x20if\x20a\x0anon-canonical\x20version\x20like\x20master\x20appears\x20in\x20a\x20go.mod\x20file.
A\x20pseudo-version\x20is\x20a\x20specially\x20formatted\x0av0.0.0-20191109021931-daa7c04131f5\x20is\x20a\x20pseudo-version.
Pseudo-versions\x20may\x20refer\x20to\x20revisions\x20for\x20which\x20no\x20
Each\x20pseudo-version\x20has\x20three\x20parts:
\x0avX.0.0\x20or\x20vX.Y.Z-0),\x20which\x20is\x20either\x20derived\x20from\x20a\x0asemantic\x20version\x20tag\x20that\x20precedes\x20the\x20revision\x20or\x20vX.0.0\x20if\x20there\x20is\x20no\x0asuch\x20tag.yymmddhhmmss),\x20which\x20is\x20the\x20UTC\x20time\x20the\x20revision\x20was\x20created.\x0aIn\x20Git,\x20this\x20is\x20the\x20commit\x20time,\x20not\x20the\x20author\x20time.abcdefabcdef),\x20which\x20is\x20a\x2012-character\x20prefix\x20of\x20the\x0acommit\x20hash,\x20or\x20in\x20Subversion,\x20a\x20zero-padded\x20revision\x20number.Each\x20pseudo-version\x20may\x20be\x20in\x20one\x20of\x20three\x20forms,\x20depending\x20on\x20the\x20base\x20version.\x0aThese\x20forms\x20ensure\x20that\x20a\x20pseudo-version\x20compares\x20higher\x20than\x20its\x20base\x20version,\x0abut\x20lower\x20than\x20the\x20next\x20tagged\x20version.
\x0avX.0.0-yyyymmddhhmmss-abcdefabcdef\x20is\x20used\x20when\x20there\x20is\x20no\x20known\x20base\x0aversion.\x20As\x20with\x20all\x20versions,\x20the\x20major\x20version\x20X\x20must\x20match\x20the\x20module's\x0avX.Y.Z-pre.0.yyyymmddhhmmss-abcdefabcdef\x20is\x20used\x20when\x20the\x20base\x20version\x20is\x0aa\x20pre-release\x20version\x20like\x20vX.Y.Z-pre.vX.Y.(Z+1)-0.yyyymmddhhmmss-abcdefabcdef\x20is\x20used\x20when\x20the\x20base\x20version\x20is\x0aa\x20release\x20version\x20like\x20vX.Y.Z.\x20For\x20example,\x20if\x20the\x20base\x20version\x20is\x0av1.2.3,\x20a\x20pseudo-version\x20might\x20be\x20v1.2.4-0.20191109021931-daa7c04131f5.More\x20than\x20one\x20pseudo-version\x20may\x20refer\x20to\x20the\x20same\x20commit\x20by\x20using\x20different\x0abase\x20versions.\x20This\x20happens\x20naturally\x20when\x20a\x20lower\x20version\x20is\x20tagged\x20after\x20a\x0apseudo-version\x20is\x20written.
\x0aThese\x20forms\x20give\x20pseudo-versions\x20two\x20useful\x20properties:
\x0aThe\x20go\x20command\x20performs\x20several\x20checks\x20to\x20ensure\x20that\x20module\x20authors\x20have\x0acontrol\x20over\x20how\x20pseudo-versions\x20are\x20compared\x20with\x20other\x20versions\x20and\x20that\x0apseudo-versions\x20refer\x20to\x20revisions\x20that\x20are\x20actually\x20part\x20of\x20a\x20module's\x0acommit\x20history.
v1.999.999-99999999999999-daa7c04131f5.Pseudo-versions\x20never\x20need\x20to\x20be\x20typed\x20by\x20hand.\x20Many\x20commands\x20accept\x0aa\x20commit\x20hash\x20or\x20a\x20branch\x20name\x20and\x20will\x20translate\x20it\x20into\x20a\x20pseudo-version\x0a(or\x20tagged\x20version\x20if\x20available)\x20automatically.\x20For\x20example:
\x0ago\x20get\x20-d\x20example.com/mod@master\x0ago\x20list\x20-m\x20-json\x20example.com/mod@abcd1234\x0aStarting\x20with\x20major\x20version\x202,\x20module\x20paths\x20must\x20have\x20a\x20/v2\x20that\x20matches\x20the\x20major\x0aversion.\x20For\x20example,\x20if\x20a\x20module\x20has\x20the\x20path\x20example.com/mod\x20at\x20v1.0.0,\x20it\x0amust\x20have\x20the\x20path\x20example.com/mod/v2\x20at\x20version\x20v2.0.0.
Major\x20version\x20suffixes\x20implement\x20the\x20
\x0a\x0aIf\x20an\x20old\x20package\x20and\x20a\x20new\x20package\x20have\x20the\x20same\x20import\x20path,\x0athe\x20new\x20package\x20must\x20be\x20backwards\x20compatible\x20with\x20the\x20old\x20package.
\x0a
By\x20definition,\x20packages\x20in\x20a\x20new\x20major\x20version\x20of\x20a\x20module\x20are\x20not\x20backwards\x0acompatible\x20with\x20the\x20corresponding\x20packages\x20in\x20the\x20previous\x20major\x20version.\x0aConsequently,\x20starting\x20with\x20v2,\x20packages\x20need\x20new\x20import\x20paths.\x20This\x20is\x0aaccomplished\x20by\x20adding\x20a\x20major\x20version\x20suffix\x20to\x20the\x20module\x20path.\x20Since\x20the\x0amodule\x20path\x20is\x20a\x20prefix\x20of\x20the\x20import\x20path\x20for\x20each\x20package\x20within\x20the\x20module,\x0aadding\x20the\x20major\x20version\x20suffix\x20to\x20the\x20module\x20path\x20provides\x20a\x20distinct\x20import\x0apath\x20for\x20each\x20incompatible\x20version.
Major\x20version\x20suffixes\x20are\x20not\x20allowed\x20at\x20major\x20versions\x20v0\x20or\x20v1.\x20There\x20is\x0ano\x20need\x20to\x20change\x20the\x20module\x20path\x20between\x20v0\x20and\x20v1\x20because\x20v0\x20versions\x0aare\x20unstable\x20and\x20have\x20no\x20compatibility\x20guarantee.\x20Additionally,\x20for\x20most\x0amodules,\x20v1\x20is\x20backwards\x20compatible\x20with\x20the\x20last\x20v0\x20version;\x20a\x20v1\x20version\x0aacts\x20as\x20a\x20commitment\x20to\x20compatibility,\x20rather\x20than\x20an\x20indication\x20of\x0aincompatible\x20changes\x20compared\x20with\x20v0.
As\x20a\x20special\x20case,\x20modules\x20paths\x20starting\x20with\x20gopkg.in/\x20must\x20always\x20have\x20a\x0amajor\x20version\x20suffix,\x20even\x20at\x20v0\x20and\x20v1.\x20The\x20suffix\x20must\x20start\x20with\x20a\x20dot\x0arather\x20than\x20a\x20slash\x20(for\x20example,\x20gopkg.in/yaml.v2).
Major\x20version\x20suffixes\x20let\x20multiple\x20major\x20versions\x20of\x20a\x20module\x20coexist\x20in\x20the\x0asame\x20build.\x20This\x20may\x20be\x20necessary\x20due\x20to\x20a\x20
Many\x20Go\x20projects\x20released\x20versions\x20at\x20v2\x20or\x20higher\x20without\x20using\x20a\x20major\x0aversion\x20suffix\x20before\x20migrating\x20to\x20modules\x20(perhaps\x20before\x20modules\x20were\x20even\x0aintroduced).\x20These\x20versions\x20are\x20annotated\x20with\x20a\x20+incompatible\x20build\x20tag\x20(for\x0aexample,\x20v2.0.0+incompatible).\x20See\x20
When\x20the\x20go\x20command\x20loads\x20a\x20package\x20using\x20a\x20
The\x20go\x20command\x20starts\x20by\x20searching\x20the\x20example.com/a/b\x20is\x20imported,\x20and\x20the\x20module\x20example.com/a\x20is\x20in\x20the\x0abuild\x20list,\x20the\x20go\x20command\x20will\x20check\x20whether\x20example.com/a\x20contains\x20the\x0apackage,\x20in\x20the\x20directory\x20b.\x20At\x20least\x20one\x20file\x20with\x20the\x20.go\x20extension\x20must\x0abe\x20present\x20in\x20a\x20directory\x20for\x20it\x20to\x20be\x20considered\x20a\x20package.\x20go\x20command\x20will\x20attempt\x20to\x0afind\x20a\x20new\x20module\x20(unless\x20the\x20flags\x20-mod=readonly\x20or\x20-mod=vendor\x20are\x20used,\x0ain\x20which\x20case,\x20an\x20error\x20is\x20reported).
When\x20the\x20go\x20command\x20looks\x20up\x20a\x20new\x20module\x20for\x20a\x20package\x20path,\x20it\x20checks\x20the\x0aGOPROXY\x20environment\x20variable,\x20which\x20is\x20a\x20comma-separated\x20list\x20of\x20proxy\x20URLs\x20or\x0athe\x20keywords\x20direct\x20or\x20off.\x20A\x20proxy\x20URL\x20indicates\x20the\x20go\x20command\x20should\x0acontact\x20a\x20GOPROXY\x0aprotocol.\x20direct\x20indicates\x20that\x20the\x20go\x20command\x20should\x0aoff\x20indicates\x20that\x20no\x0acommunication\x20should\x20be\x20attempted.\x20The\x20GOPRIVATE\x20and\x20GONOPROXY\x20
For\x20each\x20entry\x20in\x20the\x20GOPROXY\x20list,\x20the\x20go\x20command\x20requests\x20the\x20latest\x0aversion\x20of\x20each\x20module\x20path\x20that\x20might\x20provide\x20the\x20package\x20(that\x20is,\x20each\x20prefix\x0aof\x20the\x20package\x20path).\x20For\x20each\x20successfully\x20requested\x20module\x20path,\x20the\x20go\x0acommand\x20will\x20download\x20the\x20module\x20at\x20the\x20latest\x20version\x20and\x20check\x20whether\x20the\x0amodule\x20contains\x20the\x20requested\x20package.\x20If\x20one\x20or\x20more\x20modules\x20contain\x20the\x0arequested\x20package,\x20the\x20module\x20with\x20the\x20longest\x20path\x20is\x20used.\x20If\x20one\x20or\x20more\x0amodules\x20are\x20found\x20but\x20none\x20contain\x20the\x20requested\x20package,\x20an\x20error\x20is\x0areported.\x20If\x20no\x20modules\x20are\x20found,\x20the\x20go\x20command\x20tries\x20the\x20next\x20entry\x20in\x20the\x0aGOPROXY\x20list.\x20If\x20no\x20entries\x20are\x20left,\x20an\x20error\x20is\x20reported.
For\x20example,\x20suppose\x20the\x20go\x20command\x20is\x20looking\x20for\x20a\x20module\x20that\x20provides\x20the\x0apackage\x20golang.org/x/net/html,\x20and\x20GOPROXY\x20is\x20set\x20to\x0ahttps://corp.example.com,https://proxy.golang.org.\x20The\x20go\x20command\x20may\x20make\x0athe\x20following\x20requests:
https://corp.example.com/\x20(in\x20parallel):\x0agolang.org/x/net/htmlgolang.org/x/netgolang.org/xgolang.orghttps://proxy.golang.org/,\x20if\x20all\x20requests\x20to\x20https://corp.example.com/\x0ahave\x20failed\x20with\x20404\x20or\x20410:\x0agolang.org/x/net/htmlgolang.org/x/netgolang.org/xgolang.orgAfter\x20a\x20suitable\x20module\x20has\x20been\x20found,\x20the\x20go\x20command\x20will\x20add\x20a\x20new\x0ago.mod\x20file.\x20This\x20ensures\x20that\x20when\x20the\x20same\x20package\x20is\x20loaded\x0ain\x20the\x20future,\x20the\x20same\x20module\x20will\x20be\x20used\x20at\x20the\x20same\x20version.\x20If\x20the\x20resolved\x0apackage\x20is\x20not\x20imported\x20by\x20a\x20package\x20in\x20the\x20main\x20module,\x20the\x20new\x20requirement\x0awill\x20have\x20an\x20//\x20indirect\x20comment.
go.mod\x20filesA\x20module\x20is\x20defined\x20by\x20a\x20UTF-8\x20encoded\x20text\x20file\x20named\x20go.mod\x20in\x20its\x20root\x0adirectory.\x20The\x20go.mod\x20file\x20is\x20line-oriented.\x20Each\x20line\x20holds\x20a\x20single\x0adirective,\x20made\x20up\x20of\x20a\x20keyword\x20followed\x20by\x20arguments.\x20For\x20example:
module\x20example.com/my/thing\x0a\x0ago\x201.12\x0a\x0arequire\x20example.com/other/thing\x20v1.0.2\x0arequire\x20example.com/new/thing/v2\x20v2.3.4\x0aexclude\x20example.com/old/thing\x20v1.2.3\x0areplace\x20example.com/bad/thing\x20v1.4.5\x20=>\x20example.com/good/thing\x20v1.4.5\x0aThe\x20leading\x20keyword\x20can\x20be\x20factored\x20out\x20of\x20adjacent\x20lines\x20to\x20create\x20a\x20block,\x0alike\x20in\x20Go\x20imports.
\x0arequire\x20(\x0a\x20\x20\x20\x20example.com/new/thing/v2\x20v2.3.4\x0a\x20\x20\x20\x20example.com/old/thing\x20v1.2.3\x0a)\x0aThe\x20go.mod\x20file\x20is\x20designed\x20to\x20be\x20human\x20readable\x20and\x20machine\x20writable.\x20The\x0ago\x20command\x20provides\x20several\x20subcommands\x20that\x20change\x20go.mod\x20files.\x20For\x0aexample,\x20go\x20get\x20can\x20upgrade\x20or\x20downgrade\x20specific\x20dependencies.\x0aCommands\x20that\x20load\x20the\x20module\x20graph\x20will\x20go.mod\x20when\x20needed.\x20go\x20mod\x20edit\x20can\x20perform\x20low-level\x20edits.\x0aThe\x0agolang.org/x/mod/modfile\x0apackage\x20can\x20be\x20used\x20by\x20Go\x20programs\x20to\x20make\x20the\x20same\x20changes\x20programmatically.
When\x20a\x20go.mod\x20file\x20is\x20parsed,\x20its\x20content\x20is\x20broken\x20into\x20a\x20sequence\x20of\x20tokens.\x0aThere\x20are\x20several\x20kinds\x20of\x20tokens:\x20whitespace,\x20comments,\x20punctuation,\x0akeywords,\x20identifiers,\x20and\x20strings.
White\x20space\x20consists\x20of\x20spaces\x20(U+0020),\x20tabs\x20(U+0009),\x20carriage\x20returns\x0a(U+000D),\x20and\x20newlines\x20(U+000A).\x20White\x20space\x20characters\x20other\x20than\x20newlines\x20have\x0ano\x20effect\x20except\x20to\x20separate\x20tokens\x20that\x20would\x20otherwise\x20be\x20combined.\x20Newlines\x0aare\x20significant\x20tokens.
\x0aComments\x20start\x20with\x20//\x20and\x20run\x20to\x20the\x20end\x20of\x20a\x20line.\x20/*\x20*/\x20comments\x20are\x0anot\x20allowed.
Punctuation\x20tokens\x20include\x20(,\x20),\x20and\x20=>.
Keywords\x20distinguish\x20different\x20kinds\x20of\x20directives\x20in\x20a\x20go.mod\x20file.\x20Allowed\x0akeywords\x20are\x20module,\x20go,\x20require,\x20replace,\x20and\x20exclude.
Identifiers\x20are\x20sequences\x20of\x20non-whitespace\x20characters,\x20such\x20as\x20module\x20paths\x0aor\x20semantic\x20versions.
\x0aStrings\x20are\x20quoted\x20sequences\x20of\x20characters.\x20There\x20are\x20two\x20kinds\x20of\x20strings:\x0ainterpreted\x20strings\x20beginning\x20and\x20ending\x20with\x20quotation\x20marks\x20(",\x20U+0022)\x20and\x0araw\x20strings\x20beginning\x20and\x20ending\x20with\x20grave\x20accents\x20(<,\x0aU+0060).\x20Interpreted\x20strings\x20may\x20contain\x20escape\x20sequences\x20consisting\x20of\x20a\x0abackslash\x20(\\,\x20U+005C)\x20followed\x20by\x20another\x20character.\x20An\x20escaped\x20quotation\x0amark\x20(\\")\x20does\x20not\x20terminate\x20an\x20interpreted\x20string.\x20The\x20unquoted\x20value\x0aof\x20an\x20interpreted\x20string\x20is\x20the\x20sequence\x20of\x20characters\x20between\x20quotation\x0amarks\x20with\x20each\x20escape\x20sequence\x20replaced\x20by\x20the\x20character\x20following\x20the\x0abackslash\x20(for\x20example,\x20\\"\x20is\x20replaced\x20by\x20",\x20\\n\x20is\x20replaced\x20by\x20n).\x0aIn\x20contrast,\x20the\x20unquoted\x20value\x20of\x20a\x20raw\x20string\x20is\x20simply\x20the\x20sequence\x20of\x0acharacters\x20between\x20grave\x20accents;\x20backslashes\x20have\x20no\x20special\x20meaning\x20within\x0araw\x20strings.
Identifiers\x20and\x20strings\x20are\x20interchangeable\x20in\x20the\x20go.mod\x20grammar.
Most\x20identifiers\x20and\x20strings\x20in\x20a\x20go.mod\x20file\x20are\x20either\x20module\x20paths\x20or\x0aversions.
A\x20module\x20path\x20must\x20satisfy\x20the\x20following\x20requirements:
\x0a/,\x20U+002F).\x20It\x20must\x20not\x20begin\x20or\x20end\x20with\x20a\x20slash.+,\x20-,\x20.,\x20_,\x20and\x20~)..,\x20U+002E).CON,\x20com1,\x20NuL,\x20and\x20so\x20on).If\x20the\x20module\x20path\x20appears\x20in\x20a\x20require\x20directive\x20and\x20is\x20not\x20replaced,\x20or\x0aif\x20the\x20module\x20paths\x20appears\x20on\x20the\x20right\x20side\x20of\x20a\x20replace\x20directive,\x0athe\x20go\x20command\x20may\x20need\x20to\x20download\x20modules\x20with\x20that\x20path,\x20and\x20some\x0aadditional\x20requirements\x20must\x20be\x20satisfied.
.,\x20U+002E),\x20and\x20dashes\x20(-,\x20U+002D);\x20it\x20must\x20contain\x20at\x20least\x20one\x20dot\x20and\x0acannot\x20start\x20with\x20a\x20dash./vN\x20where\x20N\x20looks\x20numeric\x20(ASCII\x0adigits\x20and\x20dots),\x20N\x20must\x20not\x20begin\x20with\x20a\x20leading\x20zero,\x20must\x20not\x20be\x20/v1,\x0aand\x20must\x20not\x20contain\x20any\x20dots.\x0agopkg.in/,\x20this\x20requirement\x20is\x20replaced\x20by\x20a\x0arequirement\x20that\x20the\x20path\x20follow\x20the\x20Versions\x20in\x20go.mod\x20files\x20may\x20be\x20
A\x20canonical\x20version\x20starts\x20with\x20the\x20letter\x20v,\x20followed\x20by\x20a\x20semantic\x20version\x0afollowing\x20the\x20
Most\x20other\x20identifiers\x20and\x20strings\x20may\x20be\x20used\x20as\x20non-canonical\x20versions,\x20though\x0athere\x20are\x20some\x20restrictions\x20to\x20avoid\x20problems\x20with\x20file\x20systems,\x20repositories,\x0aand\x20go.mod\x20file.\x20The\x20go\x20command\x20will\x20attempt\x20to\x0areplace\x20each\x20non-canonical\x20version\x20with\x20an\x20equivalent\x20canonical\x20version\x20when\x20it\x0aautomatically\x20go.mod\x20file.
In\x20places\x20where\x20a\x20module\x20path\x20is\x20associated\x20with\x20a\x20verison\x20(as\x20in\x20require,\x0areplace,\x20and\x20exclude\x20directives),\x20the\x20final\x20path\x20element\x20must\x20be\x20consistent\x0awith\x20the\x20version.\x20See\x20
go.mod\x20syntax\x20is\x20specified\x20below\x20using\x20Extended\x20Backus-Naur\x20Form\x20(EBNF).\x0aSee\x20the\x20
GoMod\x20=\x20{\x20Directive\x20}\x20.\x0aDirective\x20=\x20ModuleDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GoDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20RequireDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20ExcludeDirective\x20|\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20ReplaceDirective\x20.\x0aNewlines,\x20identifiers,\x20and\x20strings\x20are\x20denoted\x20with\x20newline,\x20ident,\x20and\x0astring,\x20respectively.
Module\x20paths\x20and\x20versions\x20are\x20denoted\x20with\x20ModulePath\x20and\x20Version.
ModulePath\x20=\x20ident\x20|\x20string\x20.\x20/*\x20see\x20restrictions\x20above\x20*/\x0aVersion\x20=\x20ident\x20|\x20string\x20.\x20\x20\x20\x20/*\x20see\x20restrictions\x20above\x20*/\x0amodule\x20directiveA\x20module\x20directive\x20defines\x20the\x20main\x20module's\x20go.mod\x20file\x20must\x20contain\x20exactly\x20one\x20module\x20directive.
ModuleDirective\x20=\x20"module"\x20(\x20ModulePath\x20|\x20"("\x20newline\x20ModulePath\x20newline\x20")"\x20newline\x20.\x0aExample:
\x0amodule\x20golang.org/x/net\x0ago\x20directiveA\x20go\x20directive\x20sets\x20the\x20expected\x20language\x20version\x20for\x20the\x20module.\x20The\x0aversion\x20must\x20be\x20a\x20valid\x20Go\x20release\x20version:\x20a\x20positive\x20integer\x20followed\x20by\x20a\x20dot\x0aand\x20a\x20non-negative\x20integer\x20(for\x20example,\x201.9,\x201.14).
The\x20language\x20version\x20determines\x20which\x20language\x20features\x20are\x20available\x20when\x0acompiling\x20packages\x20in\x20the\x20module.\x20Language\x20features\x20present\x20in\x20that\x20version\x0awill\x20be\x20available\x20for\x20use.\x20Language\x20features\x20removed\x20in\x20earlier\x20versions,\x0aor\x20added\x20in\x20later\x20versions,\x20will\x20not\x20be\x20available.\x20The\x20language\x20version\x20does\x20not\x0aaffect\x20build\x20tags,\x20which\x20are\x20determined\x20by\x20the\x20Go\x20release\x20being\x20used.
\x0aThe\x20language\x20version\x20is\x20also\x20used\x20to\x20enable\x20features\x20in\x20the\x20go\x20command.\x20For\x0aexample,\x20automatic\x20go\x20version\x20of\x0a1.14\x20or\x20higher.
A\x20go.mod\x20file\x20may\x20contain\x20at\x20most\x20one\x20go\x20directive.\x20Most\x20commands\x20will\x20add\x20a\x0ago\x20directive\x20with\x20the\x20current\x20Go\x20version\x20if\x20one\x20is\x20not\x20present.
GoDirective\x20=\x20"go"\x20GoVersion\x20newline\x20.\x0aGoVersion\x20=\x20string\x20|\x20ident\x20.\x20\x20/*\x20valid\x20release\x20version;\x20see\x20above\x20*/\x0aExample:
\x0ago\x201.14\x0arequire\x20directiveA\x20require\x20directive\x20declares\x20a\x20minimum\x20required\x20version\x20of\x20a\x20given\x20module\x0adependency.\x20For\x20each\x20required\x20module\x20version,\x20the\x20go\x20command\x20loads\x20the\x0ago.mod\x20file\x20for\x20that\x20version\x20and\x20incorporates\x20the\x20requirements\x20from\x20that\x0afile.\x20Once\x20all\x20requirements\x20have\x20been\x20loaded,\x20the\x20go\x20command\x20resolves\x20them\x0ausing\x20
The\x20go\x20command\x20automatically\x20adds\x20//\x20indirect\x20comments\x20for\x20some\x0arequirements.\x20An\x20//\x20indirect\x20comment\x20indicates\x20that\x20no\x20package\x20from\x20the\x0arequired\x20module\x20is\x20directly\x20imported\x20by\x20any\x20package\x20in\x20the\x20main\x20module.\x0aThe\x20go\x20command\x20adds\x20an\x20indirect\x20requirement\x20when\x20the\x20selected\x20version\x20of\x20a\x0amodule\x20is\x20higher\x20than\x20what\x20is\x20already\x20implied\x20(transitively)\x20by\x20the\x20main\x0amodule's\x20other\x20dependencies.\x20That\x20may\x20occur\x20because\x20of\x20an\x20explicit\x20upgrade\x0a(go\x20get\x20-u),\x20removal\x20of\x20some\x20other\x20dependency\x20that\x20previously\x20imposed\x20the\x0arequirement\x20(go\x20mod\x20tidy),\x20or\x20a\x20dependency\x20that\x20imports\x20a\x20package\x20without\x0aa\x20corresponding\x20requirement\x20in\x20its\x20own\x20go.mod\x20file\x20(such\x20as\x20a\x20dependency\x0athat\x20lacks\x20a\x20go.mod\x20file\x20altogether).
RequireDirective\x20=\x20"require"\x20(\x20RequireSpec\x20|\x20"("\x20newline\x20{\x20RequireSpec\x20}\x20")"\x20newline\x20)\x20.\x0aRequireSpec\x20=\x20ModulePath\x20Version\x20newline\x20.\x0aExample:
\x0arequire\x20golang.org/x/net\x20v1.2.3\x0a\x0arequire\x20(\x0a\x20\x20\x20\x20golang.org/x/crypto\x20v1.4.5\x20//\x20indirect\x0a\x20\x20\x20\x20golang.org/x/text\x20v1.6.7\x0a)\x0aexclude\x20directiveAn\x20exclude\x20directive\x20prevents\x20a\x20module\x20version\x20from\x20being\x20loaded\x20by\x20the\x20go\x0acommand.\x20If\x20an\x20excluded\x20version\x20is\x20referenced\x20by\x20a\x20require\x20directive\x20in\x20a\x0ago.mod\x20file,\x20the\x20go\x20command\x20will\x20list\x20available\x20versions\x20for\x20the\x20module\x20(as\x0ashown\x20with\x20go\x20list\x20-m\x20-versions)\x20and\x20will\x20load\x20the\x20next\x20higher\x20non-excluded\x0aversion\x20instead.\x20Both\x20release\x20and\x20pre-release\x20versions\x20are\x20considered\x20for\x20this\x0apurpose,\x20but\x20pseudo-versions\x20are\x20not.\x20If\x20there\x20are\x20no\x20higher\x20versions,\x0athe\x20go\x20command\x20will\x20report\x20an\x20error.\x20Note\x20that\x20this\x20
exclude\x20directives\x20only\x20apply\x20in\x20the\x20main\x20module's\x20go.mod\x20file\x20and\x20are\x0aignored\x20in\x20other\x20modules.\x20See\x20
ExcludeDirective\x20=\x20"exclude"\x20(\x20ExcludeSpec\x20|\x20"("\x20newline\x20{\x20ExcludeSpec\x20}\x20")"\x20)\x20.\x0aExcludeSpec\x20=\x20ModulePath\x20Version\x20newline\x20.\x0aExample:
\x0aexclude\x20golang.org/x/net\x20v1.2.3\x0a\x0aexclude\x20(\x0a\x20\x20\x20\x20golang.org/x/crypto\x20v1.4.5\x0a\x20\x20\x20\x20golang.org/x/text\x20v1.6.7\x0a)\x0areplace\x20directiveA\x20replace\x20directive\x20replaces\x20the\x20contents\x20of\x20a\x20specific\x20version\x20of\x20a\x20module,\x0aor\x20all\x20versions\x20of\x20a\x20module,\x20with\x20contents\x20found\x20elsewhere.\x20The\x20replacement\x0amay\x20be\x20specified\x20with\x20either\x20another\x20module\x20path\x20and\x20version,\x20or\x20a\x0aplatform-specific\x20file\x20path.
If\x20a\x20version\x20is\x20present\x20on\x20the\x20left\x20side\x20of\x20the\x20arrow\x20(=>),\x20only\x20that\x20specific\x0aversion\x20of\x20the\x20module\x20is\x20replaced;\x20other\x20versions\x20will\x20be\x20accessed\x20normally.\x0aIf\x20the\x20left\x20version\x20is\x20omitted,\x20all\x20versions\x20of\x20the\x20module\x20are\x20replaced.
If\x20the\x20path\x20on\x20the\x20right\x20side\x20of\x20the\x20arrow\x20is\x20an\x20absolute\x20or\x20relative\x20path\x0a(beginning\x20with\x20./\x20or\x20../),\x20it\x20is\x20interpreted\x20as\x20the\x20local\x20file\x20path\x20to\x20the\x0areplacement\x20module\x20root\x20directory,\x20which\x20must\x20contain\x20a\x20go.mod\x20file.\x20The\x0areplacement\x20version\x20must\x20be\x20omitted\x20in\x20this\x20case.
If\x20the\x20path\x20on\x20the\x20right\x20side\x20is\x20not\x20a\x20local\x20path,\x20it\x20must\x20be\x20a\x20valid\x20module\x0apath.\x20In\x20this\x20case,\x20a\x20version\x20is\x20required.\x20The\x20same\x20module\x20version\x20must\x20not\x0aalso\x20appear\x20in\x20the\x20build\x20list.
\x0aRegardless\x20of\x20whether\x20a\x20replacement\x20is\x20specified\x20with\x20a\x20local\x20path\x20or\x20module\x0apath,\x20if\x20the\x20replacement\x20module\x20has\x20a\x20go.mod\x20file,\x20its\x20module\x20directive\x0amust\x20match\x20the\x20module\x20path\x20it\x20replaces.
replace\x20directives\x20only\x20apply\x20in\x20the\x20main\x20module's\x20go.mod\x20file\x0aand\x20are\x20ignored\x20in\x20other\x20modules.\x20See\x20
ReplaceDirective\x20=\x20"replace"\x20(\x20ReplaceSpec\x20|\x20"("\x20newline\x20{\x20ReplaceSpec\x20}\x20")"\x20newline\x20")"\x20)\x20.\x0aReplaceSpec\x20=\x20ModulePath\x20[\x20Version\x20]\x20"=>"\x20FilePath\x20newline\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20|\x20ModulePath\x20[\x20Version\x20]\x20"=>"\x20ModulePath\x20Version\x20newline\x20.\x0aFilePath\x20=\x20/*\x20platform-specific\x20relative\x20or\x20absolute\x20file\x20path\x20*/\x0aExample:
\x0areplace\x20golang.org/x/net\x20v1.2.3\x20=>\x20example.com/fork/net\x20v1.4.5\x0a\x0areplace\x20(\x0a\x20\x20\x20\x20golang.org/x/net\x20v1.2.3\x20=>\x20example.com/fork/net\x20v1.4.5\x0a\x20\x20\x20\x20golang.org/x/net\x20=>\x20example.com/fork/net\x20v1.4.5\x0a\x20\x20\x20\x20golang.org/x/net\x20v1.2.3\x20=>\x20./fork/net\x0a\x20\x20\x20\x20golang.org/x/net\x20=>\x20./fork/net\x0a)\x0aThe\x20go\x20command\x20automatically\x20updates\x20go.mod\x20when\x20it\x20uses\x20the\x20module\x20graph\x20if\x0asome\x20information\x20is\x20missing\x20or\x20go.mod\x20doesn't\x20accurately\x20reflect\x20reality.\x20\x20For\x0aexample,\x20consider\x20this\x20go.mod\x20file:
module\x20example.com/M\x0a\x0arequire\x20(\x0a\x20\x20\x20\x20example.com/A\x20v1\x0a\x20\x20\x20\x20example.com/B\x20v1.0.0\x0a\x20\x20\x20\x20example.com/C\x20v1.0.0\x0a\x20\x20\x20\x20example.com/D\x20v1.2.3\x0a\x20\x20\x20\x20example.com/E\x20dev\x0a)\x0a\x0aexclude\x20example.com/D\x20v1.2.3\x0aThe\x20update\x20rewrites\x20non-canonical\x20version\x20identifiers\x20to\x0aexample.com/A's\x20v1\x0abecomes\x20v1.0.0,\x20and\x20example.com/E's\x20dev\x20becomes\x20the\x20pseudo-version\x20for\x20the\x0alatest\x20commit\x20on\x20the\x20dev\x20branch,\x20perhaps\x20v0.0.0-20180523231146-b3f5c0f6e5f1.
The\x20update\x20modifies\x20requirements\x20to\x20respect\x20exclusions,\x20so\x20the\x20requirement\x20on\x0athe\x20excluded\x20example.com/D\x20v1.2.3\x20is\x20updated\x20to\x20use\x20the\x20next\x20available\x20version\x0aof\x20example.com/D,\x20perhaps\x20v1.2.4\x20or\x20v1.3.0.
The\x20update\x20removes\x20redundant\x20or\x20misleading\x20requirements.\x20For\x20example,\x20if\x0aexample.com/A\x20v1.0.0\x20itself\x20requires\x20example.com/B\x20v1.2.0\x20and\x20example.com/C\x20v1.0.0,\x20then\x20go.mod's\x20requirement\x20of\x20example.com/B\x20v1.0.0\x20is\x20misleading\x0a(superseded\x20by\x20example.com/A's\x20need\x20for\x20v1.2.0),\x20and\x20its\x20requirement\x20of\x0aexample.com/C\x20v1.0.0\x20is\x20redundant\x20(implied\x20by\x20example.com/A's\x20need\x20for\x20the\x0asame\x20version),\x20so\x20both\x20will\x20be\x20removed.\x20If\x20the\x20main\x20module\x20contains\x20packages\x0athat\x20directly\x20import\x20packages\x20from\x20example.com/B\x20or\x20example.com/C,\x20then\x20the\x0arequirements\x20will\x20be\x20kept\x20but\x20updated\x20to\x20the\x20actual\x20versions\x20being\x20used.
Finally,\x20the\x20update\x20reformats\x20the\x20go.mod\x20in\x20a\x20canonical\x20formatting,\x20so\x0athat\x20future\x20mechanical\x20changes\x20will\x20result\x20in\x20minimal\x20diffs.\x20The\x20go\x20command\x0awill\x20not\x20update\x20go.mod\x20if\x20only\x20formatting\x20changes\x20are\x20needed.
Because\x20the\x20module\x20graph\x20defines\x20the\x20meaning\x20of\x20import\x20statements,\x20any\x20commands\x0athat\x20load\x20packages\x20also\x20use\x20and\x20therefore\x20update\x20go.mod,\x20including\x20go\x20build,\x0ago\x20get,\x20go\x20install,\x20go\x20list,\x20go\x20test,\x20go\x20mod\x20graph,\x20go\x20mod\x20tidy,\x20and\x0ago\x20mod\x20why.
The\x20-mod=readonly\x20flag\x20prevents\x20commands\x20from\x20automatically\x20updating\x0ago.mod.\x20However,\x20if\x20a\x20command\x20needs\x20to\x20perform\x20an\x20action\x20that\x20would\x0aupdate\x20to\x20go.mod,\x20it\x20will\x20report\x20an\x20error.\x20For\x20example,\x20if\x0ago\x20build\x20is\x20asked\x20to\x20build\x20a\x20package\x20not\x20provided\x20by\x20any\x20module\x20in\x20the\x20build\x0alist,\x20go\x20build\x20will\x20report\x20an\x20error\x20instead\x20of\x20looking\x20up\x20the\x20module\x20and\x0aupdating\x20requirements\x20in\x20go.mod.
Go\x20uses\x20an\x20algorithm\x20called\x20Minimal\x20version\x20selection\x20(MVS)\x20to\x20select\x0aa\x20set\x20of\x20module\x20versions\x20to\x20use\x20when\x20building\x20packages.\x20MVS\x20is\x20described\x20in\x0adetail\x20in\x20
Conceptually,\x20MVS\x20operates\x20on\x20a\x20directed\x20graph\x20of\x20modules,\x20specified\x20with\x0ago.mod\x20files.\x20Each\x20vertex\x20in\x20the\x20graph\x20represents\x20a\x0amodule\x20version.\x20Each\x20edge\x20represents\x20a\x20minimum\x20required\x20version\x20of\x20a\x20dependency,\x0aspecified\x20using\x20a\x20require\x0adirective.\x20replace\x20and\x20exclude\x0adirectives\x20in\x20the\x20main\x20module's\x20go.mod\x20file\x20modify\x20the\x20graph.
MVS\x20produces\x20the\x20
MVS\x20starts\x20at\x20the\x20main\x20module\x20(a\x20special\x20vertex\x20in\x20the\x20graph\x20that\x20has\x20no\x0aversion)\x20and\x20traverses\x20the\x20graph,\x20tracking\x20the\x20highest\x20required\x20version\x20of\x20each\x0amodule.\x20At\x20the\x20end\x20of\x20the\x20traversal,\x20the\x20highest\x20required\x20versions\x20comprise\x20the\x0abuild\x20list:\x20they\x20are\x20the\x20minimum\x20versions\x20that\x20satisfy\x20all\x20requirements.
\x0aThe\x20build\x20list\x20may\x20be\x20inspected\x20with\x20the\x20command\x20go\x20list\x20-m\x20all.\x20Unlike\x20other\x20dependency\x20management\x20systems,\x20the\x20build\x20list\x20is\x0anot\x20saved\x20in\x20a\x20"lock"\x20file.\x20MVS\x20is\x20deterministic,\x20and\x20the\x20build\x20list\x20doesn't\x0achange\x20when\x20new\x20versions\x20of\x20dependencies\x20are\x20released,\x20so\x20MVS\x20is\x20used\x20to\x20compute\x0ait\x20at\x20the\x20beginning\x20of\x20every\x20module-aware\x20command.
Consider\x20the\x20example\x20in\x20the\x20diagram\x20below.\x20The\x20main\x20module\x20requires\x20module\x20A\x0aat\x20version\x201.2\x20or\x20higher\x20and\x20module\x20B\x20at\x20version\x201.2\x20or\x20higher.\x20A\x201.2\x20and\x20B\x201.2\x0arequire\x20C\x201.3\x20and\x20C\x201.4,\x20respectively.\x20C\x201.3\x20and\x20C\x201.4\x20both\x20require\x20D\x201.2.
\x0aMVS\x20visits\x20and\x20loads\x20the\x20go.mod\x20file\x20for\x20each\x20of\x20the\x20module\x20versions\x0ahighlighted\x20in\x20blue.\x20At\x20the\x20end\x20of\x20the\x20graph\x20traversal,\x20MVS\x20returns\x20a\x20build\x20list\x0acontaining\x20the\x20bolded\x20versions:\x20A\x201.2,\x20B\x201.2,\x20C\x201.4,\x20and\x20D\x201.2.\x20Note\x20that\x20higher\x0aversions\x20of\x20B\x20and\x20D\x20are\x20available\x20but\x20MVS\x20does\x20not\x20select\x20them,\x20since\x20nothing\x0arequires\x20them.
The\x20content\x20of\x20a\x20module\x20(including\x20its\x20go.mod\x20file)\x20may\x20be\x20replaced\x20using\x20a\x0areplace\x20directive\x20in\x20the\x20the\x20main\x20module's\x20go.mod\x20file.\x0aA\x20replace\x20directive\x20may\x20apply\x20to\x20a\x20specific\x20version\x20of\x20a\x20module\x20or\x20to\x20all\x0aversions\x20of\x20a\x20module.
Replacements\x20change\x20the\x20module\x20graph,\x20since\x20a\x20replacement\x20module\x20may\x20have\x0adifferent\x20dependencies\x20than\x20replaced\x20versions.
\x0aConsider\x20the\x20example\x20below,\x20where\x20C\x201.4\x20has\x20been\x20replaced\x20with\x20R.\x20R\x20depends\x20on\x20D\x0a1.3\x20instead\x20of\x20D\x201.2,\x20so\x20MVS\x20returns\x20a\x20build\x20list\x20containing\x20A\x201.2,\x20B\x201.2,\x20C\x201.4\x0a(replaced\x20with\x20R),\x20and\x20D\x201.3.
\x0aA\x20module\x20may\x20also\x20be\x20excluded\x20at\x20specific\x20versions\x20using\x20an\x20exclude\x0adirective\x20in\x20the\x20main\x20module's\x20go.mod\x20file.
Exclusions\x20also\x20change\x20the\x20module\x20graph.\x20When\x20a\x20version\x20is\x20excluded,\x20it\x20is\x0aremoved\x20from\x20the\x20module\x20graph,\x20and\x20requirements\x20on\x20it\x20are\x20redirected\x20to\x20the\x0anext\x20higher\x20version.
\x0aConsider\x20the\x20example\x20below.\x20C\x201.3\x20has\x20been\x20excluded.\x20MVS\x20will\x20act\x20as\x20if\x20A\x201.2\x0arequired\x20C\x201.4\x20(the\x20next\x20higher\x20version)\x20instead\x20of\x20C\x201.3.
\x0aThe\x20go\x20get\x20command\x20may\x20be\x20used\x20to\x20upgrade\x20a\x20set\x20of\x20modules.\x20To\x0aperform\x20an\x20upgrade,\x20the\x20go\x20command\x20changes\x20the\x20module\x20graph\x20before\x20running\x20MVS\x0aby\x20adding\x20edges\x20from\x20visited\x20versions\x20to\x20upgraded\x20versions.
Consider\x20the\x20example\x20below.\x20Module\x20B\x20may\x20be\x20upgraded\x20from\x201.2\x20to\x201.3,\x20C\x20may\x20be\x0aupgraded\x20from\x201.3\x20to\x201.4,\x20and\x20D\x20may\x20be\x20upgraded\x20from\x201.2\x20to\x201.3.
\x0aUpgrades\x20(and\x20downgrades)\x20may\x20add\x20or\x20remove\x20indirect\x20dependencies.\x20In\x20this\x20case,\x0aE\x201.1\x20and\x20F\x201.1\x20appear\x20in\x20the\x20build\x20list\x20after\x20the\x20upgrade,\x20since\x20E\x201.1\x20is\x0arequired\x20by\x20B\x201.3.
\x0aTo\x20preserve\x20upgrades,\x20the\x20go\x20command\x20updates\x20the\x20requirements\x20in\x20go.mod.\x20\x20It\x0awill\x20change\x20the\x20requirement\x20on\x20B\x20to\x20version\x201.3.\x20It\x20will\x20also\x20add\x20requirements\x0aon\x20C\x201.4\x20and\x20D\x201.3\x20with\x20//\x20indirect\x20comments,\x20since\x20those\x20versions\x20would\x20not\x0abe\x20selected\x20otherwise.
The\x20go\x20get\x20command\x20may\x20also\x20be\x20used\x20to\x20downgrade\x20a\x20set\x20of\x0amodules.\x20To\x20perform\x20a\x20downgrade,\x20the\x20go\x20command\x20changes\x20the\x20module\x20graph\x20by\x0aremoving\x20versions\x20above\x20the\x20downgraded\x20versions.\x20It\x20also\x20removes\x20versions\x20of\x0aother\x20modules\x20that\x20depend\x20on\x20removed\x20versions,\x20since\x20they\x20may\x20not\x20be\x20compatible\x0awith\x20the\x20downgraded\x20versions\x20of\x20their\x20dependencies.\x20If\x20the\x20main\x20module\x20requires\x0aa\x20module\x20version\x20removed\x20by\x20downgrading,\x20the\x20requirement\x20is\x20changed\x20to\x20a\x0aprevious\x20version\x20that\x20has\x20not\x20been\x20removed.\x20If\x20no\x20previous\x20version\x20is\x20available,\x0athe\x20requirement\x20is\x20dropped.
Consider\x20the\x20example\x20below.\x20Suppose\x20that\x20a\x20problem\x20was\x20found\x20with\x20C\x201.4,\x20so\x20we\x0adowngrade\x20to\x20C\x201.3.\x20C\x201.4\x20is\x20removed\x20from\x20the\x20module\x20graph.\x20B\x201.2\x20is\x20also\x0aremoved,\x20since\x20it\x20requires\x20C\x201.4\x20or\x20higher.\x20The\x20main\x20module's\x20requirement\x20on\x20B\x0ais\x20changed\x20to\x201.1.
\x0ago\x20get\x20can\x20also\x20remove\x20dependencies\x20entirely,\x20using\x20an\x20@none\x0asuffix\x20after\x20an\x20argument.\x20This\x20works\x20similarly\x20to\x20a\x20downgrade.\x20All\x20versions\x0aof\x20the\x20named\x20module\x20are\x20removed\x20from\x20the\x20module\x20graph.
Most\x20go\x20commands\x20may\x20run\x20in\x20Module-aware\x20mode\x20or\x20GOPATH\x20mode.\x20In\x0amodule-aware\x20mode,\x20the\x20go\x20command\x20uses\x20go.mod\x20files\x20to\x20find\x20versioned\x0adependencies,\x20and\x20it\x20typically\x20loads\x20packages\x20out\x20of\x20the\x20GOPATH\x0amode,\x20the\x20go\x20command\x20ignores\x20modules;\x20it\x20looks\x20in\x20vendor\x20directories\x20and\x20in\x0aGOPATH\x20to\x20find\x20dependencies.
Module-aware\x20mode\x20is\x20active\x20by\x20default\x20whenever\x20a\x20go.mod\x20file\x20is\x20found\x20in\x20the\x0acurrent\x20directory\x20or\x20in\x20any\x20parent\x20directory.\x20For\x20more\x20fine-grained\x20control,\x20the\x0aGO111MODULE\x20environment\x20variable\x20may\x20be\x20set\x20to\x20one\x20of\x20three\x20values:\x20on,\x0aoff,\x20or\x20auto.
GO111MODULE=off,\x20the\x20go\x20command\x20ignores\x20go.mod\x20files\x20and\x20runs\x20in\x0aGOPATH\x20mode.GO111MODULE=on,\x20the\x20go\x20command\x20runs\x20in\x20module-aware\x20mode,\x20even\x20when\x0ano\x20go.mod\x20file\x20is\x20present.\x20Not\x20all\x20commands\x20work\x20without\x20a\x20go.mod\x20file:\x0asee\x20GO111MODULE=auto\x20or\x20is\x20unset,\x20the\x20go\x20command\x20runs\x20in\x20module-aware\x0amode\x20if\x20a\x20go.mod\x20file\x20is\x20present\x20in\x20the\x20current\x20directory\x20or\x20any\x20parent\x0adirectory\x20(the\x20default\x20behavior).In\x20module-aware\x20mode,\x20GOPATH\x20no\x20longer\x20defines\x20the\x20meaning\x20of\x20imports\x20during\x20a\x0abuild,\x20but\x20it\x20still\x20stores\x20downloaded\x20dependencies\x20(in\x20GOPATH/pkg/mod;\x20see\x0aGOPATH/bin,\x20unless\x0aGOBIN\x20is\x20set).
When\x20using\x20modules,\x20the\x20go\x20command\x20typically\x20satisfies\x20dependencies\x20by\x0adownloading\x20modules\x20from\x20their\x20sources\x20into\x20the\x20module\x20cache,\x20then\x20loading\x0apackages\x20from\x20those\x20downloaded\x20copies.\x20Vendoring\x20may\x20be\x20used\x20to\x20allow\x0ainteroperation\x20with\x20older\x20versions\x20of\x20Go,\x20or\x20to\x20ensure\x20that\x20all\x20files\x20used\x20for\x20a\x0abuild\x20are\x20stored\x20in\x20a\x20single\x20file\x20tree.
The\x20go\x20mod\x20vendor\x20command\x20constructs\x20a\x20directory\x20named\x20vendor\x20in\x20the\x20go\x20mod\x20tidy\x20and\x20other\x20module\x20commands,\x20ignore\x20are\x20not\x20considered\x20when\x0aconstructing\x20the\x20vendor\x20directory.
go\x20mod\x20vendor\x20also\x20creates\x20the\x20file\x20vendor/modules.txt\x20that\x20contains\x20a\x20list\x0aof\x20vendored\x20packages\x20and\x20the\x20module\x20versions\x20they\x20were\x20copied\x20from.\x20When\x0avendoring\x20is\x20enabled,\x20this\x20manifest\x20is\x20used\x20as\x20a\x20source\x20of\x20module\x20version\x0ainformation,\x20as\x20reported\x20by\x20go\x20list\x20-m\x20and\x20go\x20version\x20-m.\x20When\x20the\x20go\x20command\x20reads\x20vendor/modules.txt,\x20it\x20checks\x0athat\x20the\x20module\x20versions\x20are\x20consistent\x20with\x20go.mod.\x20If\x20go.mod\x20has\x20changed\x0asince\x20vendor/modules.txt\x20was\x20generated,\x20the\x20go\x20command\x20will\x20report\x20an\x20error.\x0ago\x20mod\x20vendor\x20should\x20be\x20run\x20again\x20to\x20update\x20the\x20vendor\x20directory.
If\x20the\x20vendor\x20directory\x20is\x20present\x20in\x20the\x20main\x20module's\x20root\x20directory,\x20it\x0awill\x20be\x20used\x20automatically\x20if\x20the\x20go\x20version\x20in\x20the\x20main\x0amodule's\x20go.mod\x20file\x20is\x201.14\x20or\x20higher.\x20To\x20explicitly\x0aenable\x20vendoring,\x20invoke\x20the\x20go\x20command\x20with\x20the\x20flag\x20-mod=vendor.\x20To\x0adisable\x20vendoring,\x20use\x20the\x20flag\x20-mod=mod.
When\x20vendoring\x20is\x20enabled,\x20go\x20build\x20and\x0ago\x20test\x20load\x20packages\x20from\x20the\x20vendor\x20directory\x20instead\x20of\x20accessing\x20the\x0anetwork\x20or\x20the\x20local\x20module\x20cache.\x20The\x20go\x20list\x20-m\x20command\x20only\x0aprints\x20information\x20about\x20modules\x20listed\x20in\x20go.mod.\x20go\x20mod\x20commands\x20such\x20as\x0ago\x20mod\x20download\x20and\x20go\x20mod\x20tidy\x20do\x20not\x0awork\x20differently\x20when\x20vendoring\x20is\x20enabled\x20and\x20will\x20still\x20download\x20modules\x20and\x0aaccess\x20the\x20module\x20cache.\x20go\x20get\x20also\x20does\x20not\x20work\x20differently\x20when\x0avendoring\x20is\x20enabled.
Unlike\x20GOPATH,\x20the\x20go\x0acommand\x20ignores\x20vendor\x20directories\x20in\x20locations\x20other\x20than\x20the\x20main\x20module's\x0aroot\x20directory.
go\x20getUsage:
\x0ago\x20get\x20[-d]\x20[-t]\x20[-u]\x20[build\x20flags]\x20[packages]\x0aExamples:
\x0a#\x20Install\x20the\x20latest\x20version\x20of\x20a\x20tool.\x0a$\x20go\x20get\x20golang.org/x/tools/cmd/goimports\x0a\x0a#\x20Upgrade\x20a\x20specific\x20module.\x0a$\x20go\x20get\x20-d\x20golang.org/x/net\x0a\x0a#\x20Upgrade\x20modules\x20that\x20provide\x20packages\x20imported\x20by\x20packages\x20in\x20the\x20main\x20module.\x0a$\x20go\x20get\x20-d\x20-u\x20./...\x0a\x0a#\x20Upgrade\x20or\x20downgrade\x20to\x20a\x20specific\x20version\x20of\x20a\x20module.\x0a$\x20go\x20get\x20-d\x20golang.org/x/text@v0.3.2\x0a\x0a#\x20Update\x20to\x20the\x20commit\x20on\x20the\x20module's\x20master\x20branch.\x0a$\x20go\x20get\x20-d\x20golang.org/x/text@master\x0a\x0a#\x20Remove\x20a\x20dependency\x20on\x20a\x20module\x20and\x20downgrade\x20modules\x20that\x20require\x20it\x0a#\x20to\x20versions\x20that\x20don't\x20require\x20it.\x0a$\x20go\x20get\x20-d\x20golang.org/x/text@none\x0aThe\x20go\x20get\x20command\x20updates\x20module\x20dependencies\x20in\x20the\x20go.mod\x0afile\x20for\x20the\x20
The\x20first\x20step\x20is\x20to\x20determine\x20which\x20modules\x20to\x20update.\x20go\x20get\x20accepts\x20a\x20list\x0aof\x20packages,\x20package\x20patterns,\x20and\x20module\x20paths\x20as\x20arguments.\x20If\x20a\x20package\x0aargument\x20is\x20specified,\x20go\x20get\x20updates\x20the\x20module\x20that\x20provides\x20the\x20package.\x0aIf\x20a\x20package\x20pattern\x20is\x20specified\x20(for\x20example,\x20all\x20or\x20a\x20path\x20with\x20a\x20...\x0awildcard),\x20go\x20get\x20expands\x20the\x20pattern\x20to\x20a\x20set\x20of\x20packages,\x20then\x20updates\x20the\x0amodules\x20that\x20provide\x20the\x20packages.\x20If\x20an\x20argument\x20names\x20a\x20module\x20but\x20not\x20a\x0apackage\x20(for\x20example,\x20the\x20module\x20golang.org/x/net\x20has\x20no\x20package\x20in\x20its\x20root\x0adirectory),\x20go\x20get\x20will\x20update\x20the\x20module\x20but\x20will\x20not\x20build\x20a\x20package.\x20If\x20no\x0aarguments\x20are\x20specified,\x20go\x20get\x20acts\x20as\x20if\x20.\x20were\x20specified\x20(the\x20package\x20in\x0athe\x20current\x20directory);\x20this\x20may\x20be\x20used\x20together\x20with\x20the\x20-u\x20flag\x20to\x20update\x0amodules\x20that\x20provide\x20imported\x20packages.
Each\x20argument\x20may\x20include\x20a\x20version\x20query\x20suffix\x20indicating\x20the\x0adesired\x20version,\x20as\x20in\x20go\x20get\x20golang.org/x/text@v0.3.0.\x20A\x20version\x20query\x0asuffix\x20consists\x20of\x20an\x20@\x20symbol\x20followed\x20by\x20a\x20v0.3.0),\x20a\x20version\x20prefix\x20(v0.3),\x0aa\x20branch\x20or\x20tag\x20name\x20(master),\x20a\x20revision\x20(1234abcd),\x20or\x20one\x20of\x20the\x20special\x0aqueries\x20latest,\x20upgrade,\x20patch,\x20or\x20none.\x20If\x20no\x20version\x20is\x20given,\x0ago\x20get\x20uses\x20the\x20@upgrade\x20query.
Once\x20go\x20get\x20has\x20resolved\x20its\x20arguments\x20to\x20specific\x20modules\x20and\x20versions,\x20go\x20get\x20will\x20add,\x20change,\x20or\x20remove\x20require\x20directives\x20in\x20the\x0amain\x20module's\x20go.mod\x20file\x20to\x20ensure\x20the\x20modules\x20remain\x20at\x20the\x20desired\x0aversions\x20in\x20the\x20future.\x20Note\x20that\x20required\x20versions\x20in\x20go.mod\x20files\x20are\x0aminimum\x20versions\x20and\x20may\x20be\x20increased\x20automatically\x20as\x20new\x20dependencies\x20are\x0aadded.\x20See\x20
Other\x20modules\x20may\x20be\x20upgraded\x20when\x20a\x20module\x20named\x20on\x20the\x20command\x20line\x20is\x20added,\x0aupgraded,\x20or\x20downgraded\x20if\x20the\x20new\x20version\x20of\x20the\x20named\x20module\x20requires\x20other\x0amodules\x20at\x20higher\x20versions.\x20For\x20example,\x20suppose\x20module\x20example.com/a\x20is\x0aupgraded\x20to\x20version\x20v1.5.0,\x20and\x20that\x20version\x20requires\x20module\x20example.com/b\x0aat\x20version\x20v1.2.0.\x20If\x20module\x20example.com/b\x20is\x20currently\x20required\x20at\x20version\x0av1.1.0,\x20go\x20get\x20example.com/a@v1.5.0\x20will\x20also\x20upgrade\x20example.com/b\x20to\x0av1.2.0.
Other\x20modules\x20may\x20be\x20downgraded\x20when\x20a\x20module\x20named\x20on\x20the\x20command\x20line\x20is\x0adowngraded\x20or\x20removed.\x20To\x20continue\x20the\x20above\x20example,\x20suppose\x20module\x0aexample.com/b\x20is\x20downgraded\x20to\x20v1.1.0.\x20Module\x20example.com/a\x20would\x20also\x20be\x0adowngraded\x20to\x20a\x20version\x20that\x20requires\x20example.com/b\x20at\x20version\x20v1.1.0\x20or\x0alower.
A\x20module\x20requirement\x20may\x20be\x20removed\x20using\x20the\x20version\x20suffix\x20@none.\x20This\x20is\x20a\x0aspecial\x20kind\x20of\x20downgrade.\x20Modules\x20that\x20depend\x20on\x20the\x20removed\x20module\x20will\x20be\x0adowngraded\x20or\x20removed\x20as\x20needed.\x20A\x20module\x20requirement\x20may\x20be\x20removed\x20even\x20if\x20one\x0aor\x20more\x20of\x20its\x20packages\x20are\x20imported\x20by\x20packages\x20in\x20the\x20main\x20module.\x20In\x20this\x0acase,\x20the\x20next\x20build\x20command\x20may\x20add\x20a\x20new\x20module\x20requirement.
If\x20a\x20module\x20is\x20needed\x20at\x20two\x20different\x20versions\x20(specified\x20explicitly\x20in\x20command\x0aline\x20arguments\x20or\x20to\x20satisfy\x20upgrades\x20and\x20downgrades),\x20go\x20get\x20will\x20report\x20an\x0aerror.
After\x20go\x20get\x20updates\x20the\x20go.mod\x20file,\x20it\x20builds\x20the\x20packages\x20named\x0aon\x20the\x20command\x20line.\x20Executables\x20will\x20be\x20installed\x20in\x20the\x20directory\x20named\x20by\x0athe\x20GOBIN\x20environment\x20variable,\x20which\x20defaults\x20to\x20$GOPATH/bin\x20or\x0a$HOME/go/bin\x20if\x20the\x20GOPATH\x20environment\x20variable\x20is\x20not\x20set.
go\x20get\x20supports\x20the\x20following\x20flags:
-d\x20flag\x20tells\x20go\x20get\x20not\x20to\x20build\x20or\x20install\x20packages.\x20When\x20-d\x20is\x0aused,\x20go\x20get\x20will\x20only\x20manage\x20dependencies\x20in\x20go.mod.-u\x20flag\x20tells\x20go\x20get\x20to\x20upgrade\x20modules\x20providing\x20packages\x0aimported\x20directly\x20or\x20indirectly\x20by\x20packages\x20named\x20on\x20the\x20command\x20line.\x0aEach\x20module\x20selected\x20by\x20-u\x20will\x20be\x20upgraded\x20to\x20its\x20latest\x20version\x20unless\x0ait\x20is\x20already\x20required\x20at\x20a\x20higher\x20version\x20(a\x20pre-release).-u=patch\x20flag\x20(not\x20-u\x20patch)\x20also\x20tells\x20go\x20get\x20to\x20upgrade\x0adependencies,\x20but\x20go\x20get\x20will\x20upgrade\x20each\x20dependency\x20to\x20the\x20latest\x20patch\x0aversion\x20(similar\x20to\x20the\x20@patch\x20version\x20query).-t\x20flag\x20tells\x20go\x20get\x20to\x20consider\x20modules\x20needed\x20to\x20build\x20tests\x0aof\x20packages\x20named\x20on\x20the\x20command\x20line.\x20When\x20-t\x20and\x20-u\x20are\x20used\x20together,\x0ago\x20get\x20will\x20update\x20test\x20dependencies\x20as\x20well.-insecure\x20flag\x20should\x20no\x20longer\x20be\x20used.\x20It\x20permits\x20go\x20get\x20to\x20resolve\x0acustom\x20import\x20paths\x20and\x20fetch\x20from\x20repositories\x20and\x20module\x20proxies\x20using\x0ainsecure\x20schemes\x20such\x20as\x20HTTP.\x20The\x20GOINSECURE\x20go\x20list\x20-mUsage:
\x0ago\x20list\x20-m\x20[-u]\x20[-versions]\x20[list\x20flags]\x20[modules]\x0aExample:
\x0a$\x20go\x20list\x20-m\x20all\x0a$\x20go\x20list\x20-m\x20-versions\x20example.com/m\x0a$\x20go\x20list\x20-m\x20-json\x20example.com/m@latest\x0aThe\x20-m\x20flag\x20causes\x20go\x20list\x20to\x20list\x20modules\x20instead\x20of\x20packages.\x20In\x20this\x0amode,\x20the\x20arguments\x20to\x20go\x20list\x20may\x20be\x20modules,\x20module\x20patterns\x20(containing\x20the\x0a...\x20wildcard),\x20all,\x20which\x20matches\x20all\x20modules\x20in\x20the\x20
When\x20listing\x20modules,\x20the\x20-f\x20flag\x20still\x20specifies\x20a\x20format\x20template\x20applied\x0ato\x20a\x20Go\x20struct,\x20but\x20now\x20a\x20Module\x20struct:
type\x20Module\x20struct\x20{\x0a\x20\x20\x20\x20Path\x20\x20\x20\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20module\x20path\x0a\x20\x20\x20\x20Version\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20module\x20version\x0a\x20\x20\x20\x20Versions\x20\x20[]string\x20\x20\x20\x20\x20//\x20available\x20module\x20versions\x20(with\x20-versions)\x0a\x20\x20\x20\x20Replace\x20\x20\x20*Module\x20\x20\x20\x20\x20\x20//\x20replaced\x20by\x20this\x20module\x0a\x20\x20\x20\x20Time\x20\x20\x20\x20\x20\x20*time.Time\x20\x20\x20//\x20time\x20version\x20was\x20created\x0a\x20\x20\x20\x20Update\x20\x20\x20\x20*Module\x20\x20\x20\x20\x20\x20//\x20available\x20update,\x20if\x20any\x20(with\x20-u)\x0a\x20\x20\x20\x20Main\x20\x20\x20\x20\x20\x20bool\x20\x20\x20\x20\x20\x20\x20\x20\x20//\x20is\x20this\x20the\x20main\x20module?\x0a\x20\x20\x20\x20Indirect\x20\x20bool\x20\x20\x20\x20\x20\x20\x20\x20\x20//\x20is\x20this\x20module\x20only\x20an\x20indirect\x20dependency\x20of\x20main\x20module?\x0a\x20\x20\x20\x20Dir\x20\x20\x20\x20\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20directory\x20holding\x20files\x20for\x20this\x20module,\x20if\x20any\x0a\x20\x20\x20\x20GoMod\x20\x20\x20\x20\x20string\x20\x20\x20\x20\x20\x20\x20//\x20path\x20to\x20go.mod\x20file\x20for\x20this\x20module,\x20if\x20any\x0a\x20\x20\x20\x20GoVersion\x20string\x20\x20\x20\x20\x20\x20\x20//\x20go\x20version\x20used\x20in\x20module\x0a\x20\x20\x20\x20Error\x20\x20\x20\x20\x20*ModuleError\x20//\x20error\x20loading\x20module\x0a}\x0a\x0atype\x20ModuleError\x20struct\x20{\x0a\x20\x20\x20\x20Err\x20string\x20//\x20the\x20error\x20itself\x0a}\x0aThe\x20default\x20output\x20is\x20to\x20print\x20the\x20module\x20path\x20and\x20then\x20information\x20about\x20the\x0aversion\x20and\x20replacement\x20if\x20any.\x20For\x20example,\x20go\x20list\x20-m\x20all\x20might\x20print:
example.com/main/module\x0agolang.org/x/text\x20v0.3.0\x20=>\x20/tmp/text\x0arsc.io/pdf\x20v0.1.1\x0aThe\x20Module\x20struct\x20has\x20a\x20String\x20method\x20that\x20formats\x20this\x20line\x20of\x20output,\x20so\x0athat\x20the\x20default\x20format\x20is\x20equivalent\x20to\x20-f\x20'{{.String}}'.
Note\x20that\x20when\x20a\x20module\x20has\x20been\x20replaced,\x20its\x20Replace\x20field\x20describes\x20the\x0areplacement\x20module\x20module,\x20and\x20its\x20Dir\x20field\x20is\x20set\x20to\x20the\x20replacement\x0amodule's\x20source\x20code,\x20if\x20present.\x20(That\x20is,\x20if\x20Replace\x20is\x20non-nil,\x20then\x20Dir\x0ais\x20set\x20to\x20Replace.Dir,\x20with\x20no\x20access\x20to\x20the\x20replaced\x20source\x20code.)
The\x20-u\x20flag\x20adds\x20information\x20about\x20available\x20upgrades.\x20When\x20the\x20latest\x20version\x0aof\x20a\x20given\x20module\x20is\x20newer\x20than\x20the\x20current\x20one,\x20list\x20-u\x20sets\x20the\x20module's\x0aUpdate\x20field\x20to\x20information\x20about\x20the\x20newer\x20module.\x20The\x20module's\x20String\x0amethod\x20indicates\x20an\x20available\x20upgrade\x20by\x20formatting\x20the\x20newer\x20version\x20in\x0abrackets\x20after\x20the\x20current\x20version.\x20For\x20example,\x20go\x20list\x20-m\x20-u\x20all\x20might\x0aprint:
example.com/main/module\x0agolang.org/x/text\x20v0.3.0\x20[v0.4.0]\x20=>\x20/tmp/text\x0arsc.io/pdf\x20v0.1.1\x20[v0.1.2]\x0a(For\x20tools,\x20go\x20list\x20-m\x20-u\x20-json\x20all\x20may\x20be\x20more\x20convenient\x20to\x20parse.)
The\x20-versions\x20flag\x20causes\x20list\x20to\x20set\x20the\x20module's\x20Versions\x20field\x20to\x20a\x0alist\x20of\x20all\x20known\x20versions\x20of\x20that\x20module,\x20ordered\x20according\x20to\x20semantic\x0aversioning,\x20lowest\x20to\x20highest.\x20The\x20flag\x20also\x20changes\x20the\x20default\x20output\x20format\x0ato\x20display\x20the\x20module\x20path\x20followed\x20by\x20the\x20space-separated\x20version\x20list.
The\x20template\x20function\x20module\x20takes\x20a\x20single\x20string\x20argument\x20that\x20must\x20be\x20a\x0amodule\x20path\x20or\x20query\x20and\x20returns\x20the\x20specified\x20module\x20as\x20a\x20Module\x20struct.\x20If\x0aan\x20error\x20occurs,\x20the\x20result\x20will\x20be\x20a\x20Module\x20struct\x20with\x20a\x20non-nil\x20Error\x0afield.
go\x20mod\x20downloadUsage:
\x0ago\x20mod\x20download\x20[-json]\x20[-x]\x20[modules]\x0aExample:
\x0a$\x20go\x20mod\x20download\x0a$\x20go\x20mod\x20download\x20golang.org/x/mod@v0.2.0\x0aThe\x20go\x20mod\x20download\x20command\x20downloads\x20the\x20named\x20modules\x20into\x20the\x20path@version.\x20With\x20no\x20arguments,\x0adownload\x20applies\x20to\x20all\x20dependencies\x20of\x20the\x20
The\x20go\x20command\x20will\x20automatically\x20download\x20modules\x20as\x20needed\x20during\x20ordinary\x0aexecution.\x20The\x20go\x20mod\x20download\x20command\x20is\x20useful\x20mainly\x20for\x20pre-filling\x20the\x0amodule\x20cache\x20or\x20for\x20loading\x20data\x20to\x20be\x20served\x20by\x20a\x20
By\x20default,\x20download\x20writes\x20nothing\x20to\x20standard\x20output.\x20It\x20prints\x20progress\x0amessages\x20and\x20errors\x20to\x20standard\x20error.
The\x20-json\x20flag\x20causes\x20download\x20to\x20print\x20a\x20sequence\x20of\x20JSON\x20objects\x20to\x0astandard\x20output,\x20describing\x20each\x20downloaded\x20module\x20(or\x20failure),\x20corresponding\x0ato\x20this\x20Go\x20struct:
type\x20Module\x20struct\x20{\x0a\x20\x20\x20\x20Path\x20\x20\x20\x20\x20string\x20//\x20module\x20path\x0a\x20\x20\x20\x20Version\x20\x20string\x20//\x20module\x20version\x0a\x20\x20\x20\x20Error\x20\x20\x20\x20string\x20//\x20error\x20loading\x20module\x0a\x20\x20\x20\x20Info\x20\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20.info\x20file\x0a\x20\x20\x20\x20GoMod\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20.mod\x20file\x0a\x20\x20\x20\x20Zip\x20\x20\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20.zip\x20file\x0a\x20\x20\x20\x20Dir\x20\x20\x20\x20\x20\x20string\x20//\x20absolute\x20path\x20to\x20cached\x20source\x20root\x20directory\x0a\x20\x20\x20\x20Sum\x20\x20\x20\x20\x20\x20string\x20//\x20checksum\x20for\x20path,\x20version\x20(as\x20in\x20go.sum)\x0a\x20\x20\x20\x20GoModSum\x20string\x20//\x20checksum\x20for\x20go.mod\x20(as\x20in\x20go.sum)\x0a}\x0aThe\x20-x\x20flag\x20causes\x20download\x20to\x20print\x20the\x20commands\x20download\x20executes\x0ato\x20standard\x20error.
go\x20mod\x20editUsage:
\x0ago\x20mod\x20edit\x20[editing\x20flags]\x20[-fmt|-print|-json]\x20[go.mod]\x0aExample:
\x0a#\x20Add\x20a\x20replace\x20directive.\x0a$\x20go\x20mod\x20edit\x20-replace\x20example.com/a@v1.0.0=./a\x0a\x0a#\x20Remove\x20a\x20replace\x20directive.\x0a$\x20go\x20mod\x20edit\x20-dropreplace\x20example.com/a@v1.0.0\x0a\x0a#\x20Set\x20the\x20go\x20version,\x20add\x20a\x20requirement,\x20and\x20print\x20the\x20file\x0a#\x20instead\x20of\x20writing\x20it\x20to\x20disk.\x0a$\x20go\x20mod\x20edit\x20-go=1.14\x20-require=example.com/m@v1.0.0\x20-print\x0a\x0a#\x20Format\x20the\x20go.mod\x20file.\x0a$\x20go\x20mod\x20edit\x20-fmt\x0a\x0a#\x20Format\x20and\x20print\x20a\x20different\x20.mod\x20file.\x0a$\x20go\x20mod\x20edit\x20-print\x20tools.mod\x0a\x0a#\x20Print\x20a\x20JSON\x20representation\x20of\x20the\x20go.mod\x20file.\x0a$\x20go\x20mod\x20edit\x20-json\x0aThe\x20go\x20mod\x20edit\x20command\x20provides\x20a\x20command-line\x20interface\x20for\x20editing\x20and\x0aformatting\x20go.mod\x20files,\x20for\x20use\x20primarily\x20by\x20tools\x20and\x20scripts.\x20go\x20mod\x20edit\x0areads\x20only\x20one\x20go.mod\x20file;\x20it\x20does\x20not\x20look\x20up\x20information\x20about\x20other\x0amodules.\x20By\x20default,\x20go\x20mod\x20edit\x20reads\x20and\x20writes\x20the\x20go.mod\x20file\x20of\x20the\x0amain\x20module,\x20but\x20a\x20different\x20target\x20file\x20can\x20be\x20specified\x20after\x20the\x20editing\x0aflags.
The\x20editing\x20flags\x20specify\x20a\x20sequence\x20of\x20editing\x20operations.
\x0a-module\x20flag\x20changes\x20the\x20module's\x20path\x20(the\x20go.mod\x20file's\x20module\x0aline).-go=version\x20flag\x20sets\x20the\x20expected\x20Go\x20language\x20version.-require=path@version\x20and\x20-droprequire=path\x20flags\x20add\x20and\x20drop\x20a\x0arequirement\x20on\x20the\x20given\x20module\x20path\x20and\x20version.\x20Note\x20that\x20-require\x0aoverrides\x20any\x20existing\x20requirements\x20on\x20path.\x20These\x20flags\x20are\x20mainly\x20for\x0atools\x20that\x20understand\x20the\x20module\x20graph.\x20Users\x20should\x20prefer\x20go\x20get\x20path@version\x20or\x20go\x20get\x20path@none,\x20which\x20make\x20other\x20go.mod\x20adjustments\x20as\x0aneeded\x20to\x20satisfy\x20constraints\x20imposed\x20by\x20other\x20modules.\x20See\x20go\x20get.-exclude=path@version\x20and\x20-dropexclude=path@version\x20flags\x20add\x20and\x20drop\x0aan\x20exclusion\x20for\x20the\x20given\x20module\x20path\x20and\x20version.\x20Note\x20that\x0a-exclude=path@version\x20is\x20a\x20no-op\x20if\x20that\x20exclusion\x20already\x20exists.-replace=old[@v]=new[@v]\x20flag\x20adds\x20a\x20replacement\x20of\x20the\x20given\x20module\x0apath\x20and\x20version\x20pair.\x20If\x20the\x20@v\x20in\x20old@v\x20is\x20omitted,\x20a\x20replacement\x0awithout\x20a\x20version\x20on\x20the\x20left\x20side\x20is\x20added,\x20which\x20applies\x20to\x20all\x20versions\x20of\x0athe\x20old\x20module\x20path.\x20If\x20the\x20@v\x20in\x20new@v\x20is\x20omitted,\x20the\x20new\x20path\x20should\x20be\x0aa\x20local\x20module\x20root\x20directory,\x20not\x20a\x20module\x20path.\x20Note\x20that\x20-replace\x0aoverrides\x20any\x20redundant\x20replacements\x20for\x20old[@v],\x20so\x20omitting\x20@v\x20will\x20drop\x0areplacements\x20for\x20specific\x20versions.-dropreplace=old[@v]\x20flag\x20drops\x20a\x20replacement\x20of\x20the\x20given\x20module\x20path\x0aand\x20version\x20pair.\x20If\x20the\x20@v\x20is\x20provided,\x20a\x20replacement\x20with\x20the\x20given\x0aversion\x20is\x20dropped.\x20An\x20existing\x20replacement\x20without\x20a\x20version\x20on\x20the\x20left\x20side\x0amay\x20still\x20replace\x20the\x20module.\x20If\x20the\x20@v\x20is\x20omitted,\x20a\x20replacement\x20without\x20a\x0aversion\x20is\x20dropped.The\x20editing\x20flags\x20may\x20be\x20repeated.\x20The\x20changes\x20are\x20applied\x20in\x20the\x20order\x20given.
\x0ago\x20mod\x20edit\x20has\x20additional\x20flags\x20that\x20control\x20its\x20output.
-fmt\x20flag\x20reformats\x20the\x20go.mod\x20file\x20without\x20making\x20other\x20changes.\x0aThis\x20reformatting\x20is\x20also\x20implied\x20by\x20any\x20other\x20modifications\x20that\x20use\x20or\x0arewrite\x20the\x20go.mod\x20file.\x20The\x20only\x20time\x20this\x20flag\x20is\x20needed\x20is\x20if\x20no\x0aother\x20flags\x20are\x20specified,\x20as\x20in\x20go\x20mod\x20edit\x20-fmt.-print\x20flag\x20prints\x20the\x20final\x20go.mod\x20in\x20its\x20text\x20format\x20instead\x20of\x0awriting\x20it\x20back\x20to\x20disk.-json\x20flag\x20prints\x20the\x20final\x20go.mod\x20in\x20JSON\x20format\x20instead\x20of\x20writing\x0ait\x20back\x20to\x20disk\x20in\x20text\x20format.\x20The\x20JSON\x20output\x20corresponds\x20to\x20these\x20Go\x20types:type\x20Module\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Path\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Version\x20string\x0a}\x0a\x0atype\x20GoMod\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Module\x20\x20Module\x0a\x20\x20\x20\x20\x20\x20\x20\x20Go\x20\x20\x20\x20\x20\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Require\x20[]Require\x0a\x20\x20\x20\x20\x20\x20\x20\x20Exclude\x20[]Module\x0a\x20\x20\x20\x20\x20\x20\x20\x20Replace\x20[]Replace\x0a}\x0a\x0atype\x20Require\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Path\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Version\x20string\x0a\x20\x20\x20\x20\x20\x20\x20\x20Indirect\x20bool\x0a}\x0a\x0atype\x20Replace\x20struct\x20{\x0a\x20\x20\x20\x20\x20\x20\x20\x20Old\x20Module\x0a\x20\x20\x20\x20\x20\x20\x20\x20New\x20Module\x0a}\x0aNote\x20that\x20this\x20only\x20describes\x20the\x20go.mod\x20file\x20itself,\x20not\x20other\x20modules\x0areferred\x20to\x20indirectly.\x20For\x20the\x20full\x20set\x20of\x20modules\x20available\x20to\x20a\x20build,\x0ause\x20go\x20list\x20-m\x20-json\x20all.\x20See\x20go\x20list\x20-m.
For\x20example,\x20a\x20tool\x20can\x20obtain\x20the\x20go.mod\x20file\x20as\x20a\x20data\x20structure\x20by\x0aparsing\x20the\x20output\x20of\x20go\x20mod\x20edit\x20-json\x20and\x20can\x20then\x20make\x20changes\x20by\x20invoking\x0ago\x20mod\x20edit\x20with\x20-require,\x20-exclude,\x20and\x20so\x20on.
Tools\x20may\x20also\x20use\x20the\x20package\x0agolang.org/x/mod/modfile\x0ato\x20parse,\x20edit,\x20and\x20format\x20go.mod\x20files.
go\x20mod\x20initUsage:
\x0ago\x20mod\x20init\x20[module-path]\x0aExample:
\x0ago\x20mod\x20init\x0ago\x20mod\x20init\x20example.com/m\x0aThe\x20go\x20mod\x20init\x20command\x20initializes\x20and\x20writes\x20a\x20new\x20go.mod\x20file\x20in\x20the\x0acurrent\x20directory,\x20in\x20effect\x20creating\x20a\x20new\x20module\x20rooted\x20at\x20the\x20current\x0adirectory.\x20The\x20go.mod\x20file\x20must\x20not\x20already\x20exist.
init\x20accepts\x20one\x20optional\x20argument,\x20the\x20init\x20will\x20attempt\x0ato\x20infer\x20the\x20module\x20path\x20using\x20import\x20comments\x20in\x20.go\x20files,\x20vendoring\x20tool\x0aconfiguration\x20files,\x20and\x20the\x20current\x20directory\x20(if\x20in\x20GOPATH).
If\x20a\x20configuration\x20file\x20for\x20a\x20vendoring\x20tool\x20is\x20present,\x20init\x20will\x20attempt\x20to\x0aimport\x20module\x20requirements\x20from\x20it.\x20init\x20supports\x20the\x20following\x20configuration\x0afiles.
GLOCKFILE\x20(Glock)Godeps/Godeps.json\x20(Godeps)Gopkg.lock\x20(dep)dependencies.tsv\x20(godeps)glide.lock\x20(glide)vendor.conf\x20(trash)vendor.yml\x20(govend)vendor/manifest\x20(gvt)vendor/vendor.json\x20(govendor)Vendoring\x20tool\x20configuration\x20files\x20can't\x20always\x20be\x20translated\x20with\x20perfect\x0afidelity.\x20For\x20example,\x20if\x20multiple\x20packages\x20within\x20the\x20same\x20repository\x20are\x0aimported\x20at\x20different\x20versions,\x20and\x20the\x20repository\x20only\x20contains\x20one\x20module,\x20the\x0aimported\x20go.mod\x20can\x20only\x20require\x20the\x20module\x20at\x20one\x20version.\x20You\x20may\x20wish\x20to\x0arun\x20go\x20list\x20-m\x20all\x20to\x20check\x20all\x20versions\x20in\x20the\x20go\x20mod\x20tidy\x20to\x20add\x20missing\x0arequirements\x20and\x20to\x20drop\x20unused\x20requirements.
go\x20mod\x20tidyUsage:
\x0ago\x20mod\x20tidy\x20[-v]\x0ago\x20mod\x20tidy\x20ensures\x20that\x20the\x20go.mod\x20file\x20matches\x20the\x20source\x20code\x20in\x20the\x0amodule.\x20It\x20adds\x20any\x20missing\x20module\x20requirements\x20necessary\x20to\x20build\x20the\x20current\x0amodule's\x20packages\x20and\x20dependencies,\x20and\x20it\x20removes\x20requirements\x20on\x20modules\x20that\x0adon't\x20provide\x20any\x20relevant\x20packages.\x20It\x20also\x20adds\x20any\x20missing\x20entries\x20to\x0ago.sum\x20and\x20removes\x20unnecessary\x20entries.
The\x20-v\x20flag\x20causes\x20go\x20mod\x20tidy\x20to\x20print\x20information\x20about\x20removed\x20modules\x0ato\x20standard\x20error.
go\x20mod\x20tidy\x20works\x20by\x20loading\x20all\x20of\x20the\x20packages\x20in\x20the\x20go\x20mod\x20tidy\x20acts\x20as\x20if\x20all\x20build\x20tags\x20are\x20enabled,\x20so\x20it\x20will\x0aconsider\x20platform-specific\x20source\x20files\x20and\x20files\x20that\x20require\x20custom\x20build\x0atags,\x20even\x20if\x20those\x20source\x20files\x20wouldn't\x20normally\x20be\x20built.\x20There\x20is\x20one\x0aexception:\x20the\x20ignore\x20build\x20tag\x20is\x20not\x20enabled,\x20so\x20a\x20file\x20with\x20the\x20build\x0aconstraint\x20//\x20+build\x20ignore\x20will\x20not\x20be\x20considered.\x20Note\x20that\x20go\x20mod\x20tidy\x0awill\x20not\x20consider\x20packages\x20in\x20the\x20main\x20module\x20in\x20directories\x20named\x20testdata\x20or\x0awith\x20names\x20that\x20start\x20with\x20.\x20or\x20_\x20unless\x20those\x20packages\x20are\x20explicitly\x0aimported\x20by\x20other\x20packages.
Once\x20go\x20mod\x20tidy\x20has\x20loaded\x20this\x20set\x20of\x20packages,\x20it\x20ensures\x20that\x20each\x20module\x0athat\x20provides\x20one\x20or\x20more\x20packages\x20either\x20has\x20a\x20require\x20directive\x20in\x20the\x20main\x0amodule's\x20go.mod\x20file\x20or\x20is\x20required\x20by\x20another\x20required\x20module.\x20\x20go\x20mod\x20tidy\x0awill\x20add\x20a\x20requirement\x20on\x20the\x20latest\x20version\x20on\x20each\x20missing\x20module\x20(see\x0alatest\x0aversion).\x20go\x20mod\x20tidy\x20will\x20remove\x20require\x20directives\x20for\x20modules\x20that\x20don't\x0aprovide\x20any\x20packages\x20in\x20the\x20set\x20described\x20above.
go\x20mod\x20tidy\x20may\x20also\x20add\x20or\x20remove\x20//\x20indirect\x20comments\x20on\x20require\x0adirectives.\x20An\x20//\x20indirect\x20comment\x20denotes\x20a\x20module\x20that\x20does\x20not\x20provide\x0apackages\x20imported\x20by\x20packages\x20in\x20the\x20main\x20module.\x20These\x20requirements\x20will\x20be\x0apresent\x20if\x20the\x20module\x20that\x20imports\x20packages\x20in\x20the\x20indirect\x20dependency\x20has\x0ano\x20go.mod\x20file.\x20They\x20may\x20also\x20be\x20present\x20if\x20the\x20indirect\x20dependency\x20is\x0arequired\x20at\x20a\x20higher\x20version\x20than\x20is\x20implied\x20by\x20the\x20module\x20graph;\x20this\x20usually\x0ahappens\x20after\x20running\x20a\x20command\x20like\x20go\x20get\x20-u\x20./....
go\x20mod\x20vendorUsage:
\x0ago\x20mod\x20vendor\x20[-v]\x0aThe\x20go\x20mod\x20vendor\x20command\x20constructs\x20a\x20directory\x20named\x20vendor\x20in\x20the\x20go\x20mod\x20tidy\x20and\x20other\x20module\x20commands,\x0aignore\x20are\x20not\x0aconsidered\x20when\x20constructing\x20the\x20vendor\x20directory.
When\x20vendoring\x20is\x20enabled,\x20the\x20go\x20command\x20will\x20load\x20packages\x20from\x20the\x20vendor\x0adirectory\x20instead\x20of\x20downloading\x20modules\x20from\x20their\x20sources\x20into\x20the\x20module\x0acache\x20and\x20using\x20packages\x20those\x20downloaded\x20copies.\x20See\x20
go\x20mod\x20vendor\x20also\x20creates\x20the\x20file\x20vendor/modules.txt\x20that\x20contains\x20a\x20list\x0aof\x20vendored\x20packages\x20and\x20the\x20module\x20versions\x20they\x20were\x20copied\x20from.\x20When\x0avendoring\x20is\x20enabled,\x20this\x20manifest\x20is\x20used\x20as\x20a\x20source\x20of\x20module\x20version\x0ainformation,\x20as\x20reported\x20by\x20go\x20list\x20-m\x20and\x20go\x20version\x20-m.\x20When\x20the\x20go\x20command\x20reads\x20vendor/modules.txt,\x20it\x20checks\x0athat\x20the\x20module\x20versions\x20are\x20consistent\x20with\x20go.mod.\x20If\x20go.mod\x20changed\x20since\x0avendor/modules.txt\x20was\x20generated,\x20go\x20mod\x20vendor\x20should\x20be\x20run\x20again.
Note\x20that\x20go\x20mod\x20vendor\x20removes\x20the\x20vendor\x20directory\x20if\x20it\x20exists\x20before\x0are-constructing\x20it.\x20Local\x20changes\x20should\x20not\x20be\x20made\x20to\x20vendored\x20packages.\x0aThe\x20go\x20command\x20does\x20not\x20check\x20that\x20packages\x20in\x20the\x20vendor\x20directory\x20have\x0anot\x20been\x20modified,\x20but\x20one\x20can\x20verify\x20the\x20integrity\x20of\x20the\x20vendor\x20directory\x0aby\x20running\x20go\x20mod\x20vendor\x20and\x20checking\x20that\x20no\x20changes\x20were\x20made.
The\x20-v\x20flag\x20causes\x20go\x20mod\x20vendor\x20to\x20print\x20the\x20names\x20of\x20vendored\x20modules\x0aand\x20packages\x20to\x20standard\x20error.
go\x20mod\x20verifyUsage:
\x0ago\x20mod\x20verify\x0ago\x20mod\x20verify\x20checks\x20that\x20dependencies\x20of\x20the\x20go\x20mod\x20verify\x20hashes\x20each\x0adownloaded\x20module\x20.zip\x20file\x20and\x20extracted\x20directory,\x20then\x0acompares\x20those\x20hashes\x20with\x20a\x20hash\x20recorded\x20when\x20the\x20module\x20was\x20first\x0adownloaded.\x20go\x20mod\x20verify\x20checks\x20each\x20module\x20in\x20the\x20go\x20list\x20-m\x20all).
If\x20all\x20the\x20modules\x20are\x20unmodified,\x20go\x20mod\x20verify\x20prints\x20"all\x20modules\x0averified".\x20Otherwise,\x20it\x20reports\x20which\x20modules\x20have\x20been\x20changed\x20and\x20exits\x20with\x0aa\x20non-zero\x20status.
Note\x20that\x20all\x20module-aware\x20commands\x20verify\x20that\x20hashes\x20in\x20the\x20main\x20module's\x0ago.sum\x20file\x20match\x20hashes\x20recorded\x20for\x20modules\x20downloaded\x20into\x20the\x20module\x0acache.\x20If\x20a\x20hash\x20is\x20missing\x20from\x20go.sum\x20(for\x20example,\x20because\x20the\x20module\x20is\x0abeing\x20used\x20for\x20the\x20first\x20time),\x20the\x20go\x20command\x20verifies\x20its\x20hash\x20using\x20the\x0aGOPRIVATE\x20or\x20GONOSUMDB).\x20See\x20
In\x20contrast,\x20go\x20mod\x20verify\x20checks\x20that\x20module\x20.zip\x20files\x20and\x20their\x20extracted\x0adirectories\x20have\x20hashes\x20that\x20match\x20hashes\x20recorded\x20in\x20the\x20module\x20cache\x20when\x20they\x0awere\x20first\x20downloaded.\x20This\x20is\x20useful\x20for\x20detecting\x20changes\x20to\x20files\x20in\x20the\x0amodule\x20cache\x20after\x20a\x20module\x20has\x20been\x20downloaded\x20and\x20verified.\x20go\x20mod\x20verify\x0adoes\x20not\x20download\x20content\x20for\x20modules\x20not\x20in\x20the\x20cache,\x20and\x20it\x20does\x20not\x20use\x0ago.sum\x20files\x20to\x20verify\x20module\x20content.\x20However,\x20go\x20mod\x20verify\x20may\x20download\x0ago.mod\x20files\x20in\x20order\x20to\x20perform\x20go.sum\x20to\x20verify\x20those\x0afiles,\x20and\x20it\x20may\x20add\x20go.sum\x20entries\x20for\x20missing\x20hashes.
go\x20version\x20-mUsage:
\x0ago\x20version\x20[-m]\x20[-v]\x20[file\x20...]\x0aExample:
\x0a#\x20Print\x20Go\x20version\x20used\x20to\x20build\x20go.\x0a$\x20go\x20version\x0a\x0a#\x20Print\x20Go\x20version\x20used\x20to\x20build\x20a\x20specific\x20executable.\x0a$\x20go\x20version\x20~/go/bin/gopls\x0a\x0a#\x20Print\x20Go\x20version\x20and\x20module\x20versions\x20used\x20to\x20build\x20a\x20specific\x20executable.\x0a$\x20go\x20version\x20-m\x20~/go/bin/gopls\x0a\x0a#\x20Print\x20Go\x20version\x20and\x20module\x20versions\x20used\x20to\x20build\x20executables\x20in\x20a\x20directory.\x0a$\x20go\x20version\x20-m\x20~/go/bin/\x0ago\x20version\x20reports\x20the\x20Go\x20version\x20used\x20to\x20build\x20each\x20executable\x20file\x20named\x0aon\x20the\x20command\x20line.
If\x20no\x20files\x20are\x20named\x20on\x20the\x20command\x20line,\x20go\x20version\x20prints\x20its\x20own\x20version\x0ainformation.
If\x20a\x20directory\x20is\x20named,\x20go\x20version\x20walks\x20that\x20directory,\x20recursively,\x20looking\x0afor\x20recognized\x20Go\x20binaries\x20and\x20reporting\x20their\x20versions.\x20By\x20default,\x20go\x20version\x20does\x20not\x20report\x20unrecognized\x20files\x20found\x20during\x20a\x20directory\x20scan.\x20The\x0a-v\x20flag\x20causes\x20it\x20to\x20report\x20unrecognized\x20files.
The\x20-m\x20flag\x20causes\x20go\x20version\x20to\x20print\x20each\x20executable's\x20embedded\x20module\x0aversion\x20information,\x20when\x20available.\x20For\x20each\x20executable,\x20go\x20version\x20-m\x20prints\x0aa\x20table\x20with\x20tab-separated\x20columns\x20like\x20the\x20one\x20below.
$\x20go\x20version\x20-m\x20~/go/bin/goimports\x0a/home/jrgopher/go/bin/goimports:\x20go1.14.3\x0a\x20\x20\x20\x20\x20\x20\x20\x20path\x20\x20\x20\x20golang.org/x/tools/cmd/goimports\x0a\x20\x20\x20\x20\x20\x20\x20\x20mod\x20\x20\x20\x20\x20golang.org/x/tools\x20\x20\x20\x20\x20\x20v0.0.0-20200518203908-8018eb2c26ba\x20\x20\x20\x20\x20\x20h1:0Lcy64USfQQL6GAJma8BdHCgeofcchQj+Z7j0SXYAzU=\x0a\x20\x20\x20\x20\x20\x20\x20\x20dep\x20\x20\x20\x20\x20golang.org/x/mod\x20\x20\x20\x20\x20\x20\x20\x20v0.2.0\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20h1:KU7oHjnv3XNWfa5COkzUifxZmxp1TyI7ImMXqFxLwvQ=\x0a\x20\x20\x20\x20\x20\x20\x20\x20dep\x20\x20\x20\x20\x20golang.org/x/xerrors\x20\x20\x20\x20v0.0.0-20191204190536-9bdfabe68543\x20\x20\x20\x20\x20\x20h1:E7g+9GITq07hpfrRu66IVDexMakfv52eLZ2CXBWiKr4=\x0aThe\x20format\x20of\x20the\x20table\x20may\x20change\x20in\x20the\x20future.\x20The\x20same\x20information\x20may\x20be\x0aobtained\x20from\x0aruntime/debug.ReadBuildInfo.
The\x20meaning\x20of\x20each\x20row\x20in\x20the\x20table\x20is\x20determined\x20by\x20the\x20word\x20in\x20the\x20first\x0acolumn.
\x0apath:\x20the\x20path\x20of\x20the\x20main\x20package\x20used\x20to\x20build\x20the\x20executable.mod:\x20the\x20module\x20containing\x20the\x20main\x20package.\x20The\x20columns\x20are\x20the\x0amodule\x20path,\x20version,\x20and\x20sum,\x20respectively.\x20The\x20(devel)\x20and\x20no\x20sum.dep:\x20a\x20module\x20that\x20provided\x20one\x20or\x20more\x20packages\x20linked\x20into\x20the\x0aexecutable.\x20Same\x20format\x20as\x20mod.=>:\x20a\x20mod\x20and\x20dep.\x20A\x20replaced\x20module\x20has\x0ano\x20sum.go\x20clean\x20-modcacheUsage:
\x0ago\x20clean\x20[-modcache]\x0aThe\x20-modcache\x20flag\x20causes\x20go\x20clean\x20to\x20remove\x20the\x20entire\x0a
This\x20is\x20usually\x20the\x20best\x20way\x20to\x20remove\x20the\x20module\x20cache.\x20By\x20default,\x20most\x20files\x0aand\x20directories\x20in\x20the\x20module\x20cache\x20are\x20read-only\x20to\x20prevent\x20tests\x20and\x20editors\x0afrom\x20unintentionally\x20changing\x20files\x20after\x20they've\x20been\x0arm\x20-r\x20to\x20fail,\x20since\x20files\x20can't\x20be\x20removed\x20without\x20first\x20making\x20their\x20parent\x0adirectories\x20writable.
The\x20-modcacherw\x20flag\x20(accepted\x20by\x20go\x20build\x20and\x0aother\x20module-aware\x20commands)\x20causes\x20new\x20directories\x20in\x20the\x20module\x20cache\x20to\x0abe\x20writable.\x20To\x20pass\x20-modcacherw\x20to\x20all\x20module-aware\x20commands,\x20add\x20it\x20to\x20the\x0aGOFLAGS\x20variable.\x20GOFLAGS\x20may\x20be\x20set\x20in\x20the\x20environment\x20or\x20with\x20go\x20env\x20-w.\x20For\x0aexample,\x20the\x20command\x20below\x20sets\x20it\x20permanently:
go\x20env\x20-w\x20GOFLAGS=-modcacherw\x0a-modcacherw\x20should\x20be\x20used\x20with\x20caution;\x20developers\x20should\x20be\x20careful\x20not\x0ato\x20make\x20changes\x20to\x20files\x20in\x20the\x20module\x20cache.\x20go\x20mod\x20verify\x0amay\x20be\x20used\x20to\x20check\x20that\x20files\x20in\x20the\x20cache\x20match\x20hashes\x20in\x20the\x20main\x20module's\x0ago.sum\x20file.
Several\x20commands\x20allow\x20you\x20to\x20specify\x20a\x20version\x20of\x20a\x20module\x20using\x20a\x20version\x0aquery,\x20which\x20appears\x20after\x20an\x20@\x20character\x20following\x20a\x20module\x20or\x20package\x20path\x0aon\x20the\x20command\x20line.
Examples:
\x0ago\x20get\x20example.com/m@latest\x0ago\x20mod\x20download\x20example.com/m@master\x0ago\x20list\x20-m\x20-json\x20example.com/m@e3702bed2\x0aA\x20version\x20query\x20may\x20be\x20one\x20of\x20the\x20following:
\x0av1.2.3,\x20which\x20selects\x20a\x0aspecific\x20version.\x20See\x20v1\x20or\x20v1.2,\x20which\x20selects\x20the\x20highest\x0aavailable\x20version\x20with\x20that\x20prefix.<v1.2.3\x20or\x20>=v1.5.6,\x20which\x20selects\x0athe\x20nearest\x20available\x20version\x20to\x20the\x20comparison\x20target\x20(the\x20lowest\x20version\x0afor\x20>\x20and\x20>=,\x20and\x20the\x20highest\x20version\x20for\x20<\x20and\x20<=).v2\x20selects\x20the\x0alatest\x20version\x20starting\x20with\x20v2,\x20not\x20the\x20branch\x20named\x20v2.latest,\x20which\x20selects\x20the\x20highest\x20available\x20release\x20version.\x20If\x0athere\x20are\x20no\x20release\x20versions,\x20latest\x20selects\x20the\x20highest\x20pre-release\x0aversion.\x20\x20If\x20there\x20no\x20tagged\x20versions,\x20latest\x20selects\x20a\x20pseudo-version\x20for\x0athe\x20commit\x20at\x20the\x20tip\x20of\x20the\x20repository's\x20default\x20branch.upgrade,\x20which\x20is\x20like\x20latest\x20except\x20that\x20if\x20the\x20module\x20is\x0acurrently\x20required\x20at\x20a\x20higher\x20version\x20than\x20the\x20version\x20latest\x20would\x20select\x0a(for\x20example,\x20a\x20pre-release),\x20upgrade\x20will\x20select\x20the\x20current\x20version.patch,\x20which\x20selects\x20the\x20latest\x20available\x20version\x20with\x20the\x20same\x0amajor\x20and\x20minor\x20version\x20numbers\x20as\x20the\x20currently\x20required\x20version.\x20If\x20no\x0aversion\x20is\x20currently\x20required,\x20patch\x20is\x20equivalent\x20to\x20latest.Except\x20for\x20queries\x20for\x20specific\x20named\x20versions\x20or\x20revisions,\x20all\x20queries\x0aconsider\x20available\x20versions\x20reported\x20by\x20go\x20list\x20-m\x20-versions\x20(see\x20go\x20list\x20-m).\x20This\x20list\x20contains\x20only\x20tagged\x20versions,\x20not\x20pseudo-versions.\x0aModule\x20versions\x20disallowed\x20by\x20go.mod\x20file\x20are\x20not\x20considered.
v1.2.2\x20and\x20v1.2.3-pre\x20are\x20available,\x20the\x0alatest\x20query\x20will\x20select\x20v1.2.2,\x20even\x20though\x20v1.2.3-pre\x20is\x20higher.\x20The\x0a<v1.2.4\x20query\x20would\x20also\x20select\x20v1.2.2,\x20even\x20though\x20v1.2.3-pre\x20is\x20closer\x0ato\x20v1.2.4.\x20If\x20no\x20release\x20or\x20pre-release\x20version\x20is\x20available,\x20the\x20latest,\x0aupgrade,\x20and\x20patch\x20queries\x20will\x20select\x20a\x20pseudo-version\x20for\x20the\x20commit\x0aat\x20the\x20tip\x20of\x20the\x20repository's\x20default\x20branch.\x20Other\x20queries\x20will\x20report\x0aan\x20error.
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go.mod\x0afiles\x20and\x20performing\x20go.mod,\x0aand\x20start\x20over.When\x20the\x20go\x20command\x20computes\x20the\x20build\x20list,\x20it\x20loads\x20the\x20go.mod\x20file\x20for\x0aeach\x20module\x20in\x20the\x20go.mod\x20file\x20is\x20not\x0ain\x20the\x20cache,\x20the\x20go\x20command\x20will\x20download\x20it\x20from\x20the\x20proxy\x20using\x20a\x0a$module/@v/$version.mod\x20request\x20(where\x20$module\x20is\x20the\x20module\x20path\x20and\x0a$version\x20is\x20the\x20version).\x20These\x20requests\x20can\x20be\x20tested\x20with\x20a\x20tool\x20like\x0acurl.\x20For\x20example,\x20the\x20command\x20below\x20downloads\x20the\x20go.mod\x20file\x20for\x0agolang.org/x/mod\x20at\x20version\x20v0.2.0:
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The\x20major\x20version\x20number\x20of\x20a\x20semantic\x20version\x20tag\x20must\x20be\x20consistent\x20with\x20the\x0amodule\x20path's\x20major\x20version\x20suffix\x20(if\x20any).\x20For\x20example,\x20the\x20tag\x20v1.0.0\x20could\x0abelong\x20to\x20the\x20module\x20example.com/mod\x20but\x20not\x20example.com/mod/v2,\x20which\x20would\x0ahave\x20tags\x20like\x20v2.0.0.
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See\x20
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go\x20get\x20example.com/mod@master\x0aThe\x20go\x20command\x20converts\x20these\x20names\x20into\x20
If\x20a\x20revision\x20is\x20tagged\x20with\x20one\x20or\x20more\x20semantic\x20version\x20tags\x20like\x20v1.2.3,\x0athe\x20tag\x20for\x20the\x20highest\x20valid\x20version\x20will\x20be\x20used.\x20The\x20go\x20command\x20only\x0aconsiders\x20semantic\x20version\x20tags\x20that\x20could\x20belong\x20to\x20the\x20target\x20module;\x20for\x0aexample,\x20the\x20tag\x20v1.5.2\x20would\x20not\x20be\x20considered\x20for\x20example.com/mod/v2\x20since\x0athe\x20major\x20version\x20doesn't\x20match\x20the\x20module\x20path's\x20suffix.
If\x20a\x20revision\x20is\x20not\x20tagged\x20with\x20a\x20valid\x20semantic\x20version\x20tag,\x20the\x20go\x20command\x0awill\x20generate\x20a\x20
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GONOPROXY\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Comma-separated\x20list\x20of\x20glob\x20patterns\x20(in\x20the\x20syntax\x20of\x20Go's\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20path.Match)\x20of\x20module\x20path\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20prefixes\x20that\x20should\x20always\x20be\x20fetched\x20directly\x20from\x20version\x20control\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20repositories,\x20not\x20from\x20module\x20proxies.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20GONOPROXY\x20is\x20not\x20set,\x20it\x20defaults\x20to\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE.\x20See\x20
GONOSUMDB\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Comma-separated\x20list\x20of\x20glob\x20patterns\x20(in\x20the\x20syntax\x20of\x20Go's\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20path.Match)\x20of\x20module\x20path\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20prefixes\x20for\x20which\x20the\x20go\x20should\x20not\x20verify\x20checksums\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20using\x20the\x20checksum\x20database.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20GONOSUMDB\x20is\x20not\x20set,\x20it\x20defaults\x20to\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE.\x20See\x20
GOPATH\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20In\x20GOPATH\x20mode,\x20the\x20GOPATH\x20variable\x20is\x20a\x20list\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20of\x20directories\x20that\x20may\x20contain\x20Go\x20code.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20In\x20module-aware\x20mode,\x20the\x20pkg/mod\x20subdirectory\x20of\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20first\x20GOPATH\x20directory.\x20Module\x20source\x20code\x20outside\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20cache\x20may\x20be\x20stored\x20in\x20any\x20directory.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20GOPATH\x20is\x20not\x20set,\x20it\x20defaults\x20to\x20the\x20go\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20subdirectory\x20of\x20the\x20user's\x20home\x20directory.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
GOPRIVATEpath.Match)\x20of\x20module\x20path\x0a\x20\x20\x20\x20\x20\x20\x20\x20prefixes\x20that\x20should\x20be\x20considered\x20private.\x20GOPRIVATE\x0a\x20\x20\x20\x20\x20\x20\x20\x20is\x20a\x20default\x20value\x20for\x20GONOPROXY\x20and\x0a\x20\x20\x20\x20\x20\x20\x20\x20GONOSUMDB.\x20GOPRIVATE\x20itself\x20has\x20no\x20other\x0a\x20\x20\x20\x20\x20\x20\x20\x20meaning.\x20See\x20GOPROXY\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Comma-separated\x20list\x20of\x20module\x20proxy\x20URLs.\x20When\x20the\x20go\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20command\x20looks\x20up\x20information\x20about\x20a\x20module,\x20it\x20will\x20contact\x20each\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20proxy\x20in\x20the\x20list,\x20in\x20sequence.\x20A\x20proxy\x20may\x20respond\x20with\x20a\x20404\x20(Not\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Found)\x20or\x20410\x20(Gone)\x20status\x20to\x20indicate\x20the\x20module\x20is\x20not\x20available\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20and\x20the\x20go\x20command\x20should\x20contact\x20the\x20next\x20proxy\x20in\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20list.\x20Any\x20other\x20error\x20will\x20cause\x20the\x20go\x20command\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20to\x20stop\x20without\x20contacting\x20other\x20proxies\x20in\x20the\x20list.\x20This\x20allows\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20a\x20proxy\x20to\x20act\x20as\x20a\x20gatekeeper,\x20for\x20example,\x20by\x20responding\x20with\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20403\x20(Forbidden)\x20for\x20modules\x20not\x20on\x20an\x20approved\x20list.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPROXY\x20URLs\x20may\x20have\x20the\x20schemes\x20https,\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20http,\x20or\x20file.\x20If\x20no\x20scheme\x20is\x20specified,\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20https\x20is\x20assumed.\x20A\x20module\x20cache\x20may\x20be\x20used\x20direclty\x20as\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20a\x20file\x20proxy:\x0a\x20\x20\x20\x20\x20\x20\x20\x20
GOPROXY=file://$(go\x20env\x20GOPATH)/pkg/mod/cache/download\x0a\x20\x20\x20\x20\x20\x20\x20\x20
Two\x20keywords\x20may\x20be\x20used\x20in\x20place\x20of\x20proxy\x20URLs:
\x0a\x20\x20\x20\x20\x20\x20\x20\x20off:\x20disallows\x20downloading\x20modules\x20from\x20any\x20source.\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20direct:\x20download\x20directly\x20from\x20version\x20control\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20repositories.\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPROXY\x20defaults\x20to\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20https://proxy.golang.org,direct.\x20Under\x20that\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20configuration,\x20the\x20go\x20command\x20will\x20first\x20contact\x20the\x20Go\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20module\x20mirror\x20run\x20by\x20Google,\x20then\x20fall\x20back\x20to\x20a\x20direct\x20connection\x20if\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20mirror\x20does\x20not\x20have\x20the\x20module.\x20See\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE\x20and\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GONOPROXY\x20environment\x20variables\x20may\x20be\x20set\x20to\x20prevent\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20specific\x20modules\x20from\x20being\x20downloaded\x20using\x20proxies.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20See\x20
GOSUMDB\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Identifies\x20the\x20name\x20of\x20the\x20checksum\x20database\x20to\x20use\x20and\x20optionally\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20its\x20public\x20key\x20and\x20URL.\x20For\x20example:\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x0aGOSUMDB=\"sum.golang.org\"\x0aGOSUMDB=\"sum.golang.org+<publickey>\"\x0aGOSUMDB=\"sum.golang.org+<publickey>\x20https://sum.golang.org\x0a\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20The\x20go\x20command\x20knows\x20the\x20public\x20key\x20of\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20sum.golang.org\x20and\x20also\x20that\x20the\x20name\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20sum.golang.google.cn\x20(available\x20inside\x20mainland\x20China)\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20connects\x20to\x20the\x20sum.golang.org\x20database;\x20use\x20of\x20any\x20other\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20database\x20requires\x20giving\x20the\x20public\x20key\x20explicitly.\x20The\x20URL\x20defaults\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20to\x20https://\x20followed\x20by\x20the\x20database\x20name.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20 \x0a\x20\x20\x20\x20\x20\x20\x20\x20 \x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20If\x20 \x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20See\x20GOSUMDB\x20defaults\x20to\x20sum.golang.org,\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20Go\x20checksum\x20database\x20run\x20by\x20Google.\x20See\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOSUMDB\x20is\x20set\x20to\x20off\x20or\x20if\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20go\x20get\x20is\x20invoked\x20with\x20the\x20-insecure\x20flag,\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20checksum\x20database\x20is\x20not\x20consulted,\x20and\x20all\x20unrecognized\x20modules\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20are\x20accepted,\x20at\x20the\x20cost\x20of\x20giving\x20up\x20the\x20security\x20guarantee\x20of\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20verified\x20repeatable\x20downloads\x20for\x20all\x20modules.\x20A\x20better\x20way\x20to\x20bypass\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20the\x20checksum\x20database\x20for\x20specific\x20modules\x20is\x20to\x20use\x20the\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20GOPRIVATE\x20or\x20GONOSUMDB\x20environment\x0a\x20\x20\x20\x20\x20\x20\x20\x20\x20\x20variables.\x0a\x20\x20\x20\x20\x20\x20\x20\x20
foo_linux_amd64.go)\x20or\x20with\x20build\x20constraint\x20comments\x0a(for\x20example,\x20//\x20+build\x20linux,amd64).\x20See\x20
go\x20build,\x20go\x20list,\x20or\x20go\x20test.\x20The\x20build\x20list\x20is\x0adetermined\x20from\x20the\x20go.mod\x0afile\x20and\x20go.mod\x20files\x20in\x20transitively\x20required\x20modules\x0ausing\x20
+incompatible.\x20For\x20example,\x20v1.2.3\x0ais\x20a\x20canonical\x20version,\x20but\x20v1.2.3+meta\x20is\x20not.
go.mod\x20file:\x20The\x20file\x20that\x20defines\x20a\x20module's\x20path,\x20requirements,\x20and\x0aother\x20metadata.\x20Appears\x20in\x20the\x20go.mod\x0afiles.
go\x20command\x20is\x20invoked.
1\x20in\x20v1.2.3).\x20In\x0aa\x20release\x20with\x20incompatible\x20changes,\x20the\x20major\x20version\x20must\x20be\x20incremented,\x20and\x0athe\x20minor\x20and\x20patch\x20versions\x20must\x20be\x20set\x20to\x200.\x20Semantic\x20versions\x20with\x20major\x0aversion\x200\x20are\x20considered\x20unstable.
example.com/mod/v2\x20in\x20the\x20repository\x20with\x20example.com/mod\x20may\x20be\x20defined\x20in\x20the\x0arepository\x20root\x20directory\x20or\x20the\x20major\x20version\x20subdirectory\x20v2.\x20See\x20
/v2\x20in\x20example.com/mod/v2.\x20Major\x20version\x20suffixes\x20are\x0arequired\x20at\x20v2.0.0\x20and\x20later\x20and\x20are\x20not\x20allowed\x20at\x20earlier\x20versions.\x20See\x0athe\x20section\x20on\x20
2\x20in\x20v1.2.3).\x20In\x0aa\x20release\x20with\x20new,\x20backwards\x20compatible\x20functionality,\x20the\x20minor\x20version\x20must\x0abe\x20incremented,\x20and\x20the\x20patch\x20version\x20must\x20be\x20set\x20to\x200.
GOPATH/pkg/mod.\x20See\x20
require\x20statement\x20in\x20a\x20go.mod\x20file\x20(subject\x20to\x20replace\x20and\x0aexclude\x20statements\x20in\x20the\x20main\x20module's\x20go.mod\x20file.
"golang.org/x/net".
GOPROXY\x0aprotocol.\x20The\x20go\x20command\x20downloads\x20version\x20information,\x0ago.mod\x20files,\x20and\x20module\x20zip\x20files\x20from\x20module\x20proxies.
go.mod\x20file\x20that\x0adefines\x20a\x20module.
"golang.org/x/net/html"\x20is\x20the\x20package\x20path\x20for\x20the\x20package\x20in\x20the\x0amodule\x20"golang.org/x/net"\x20in\x20the\x20"html"\x20subdirectory.\x20Synonym\x20of\x0a
3\x20in\x20v1.2.3).\x20In\x0aa\x20release\x20with\x20no\x20changes\x20to\x20the\x20module's\x20public\x20interface,\x20the\x20patch\x20version\x0amust\x20be\x20incremented.
v1.2.3-beta4.\x20Pre-release\x20versions\x20are\x20considered\x20unstable\x20and\x20are\x20not\x0aassumed\x20to\x20be\x20compatible\x20with\x20other\x20versions.\x20A\x20pre-release\x20version\x20sorts\x20before\x0athe\x20corresponding\x20release\x20version:\x20v1.2.3-pre\x20comes\x20before\x20v1.2.3.\x20See\x20also\x0a
v0.0.0-20191109021931-daa7c04131f5.\x20Used\x20for\x20
v1.2.3,\x20not\x20v1.2.3-pre.\x20See\x20also\x20
v\x20followed\x20by\x20a\x20semantic\x20version.\x20See\x20the\x20section\x20on\x0a