make gqlgen generate 10x faster in some projects

codegen/config/config.go

@@ -136,7 +136,7 @@ func (c *PackageConfig) normalize() error {
 	// If Package is not set, first attempt to load the package at the output dir. If that fails
 	// fallback to just the base dir name of the output filename.
 	if c.Package == "" {
-		c.Package = code.NameForPackage(c.ImportPath())
+		c.Package = code.NameForDir(c.Dir())
 	}
 
 	return nil

go.mod

@@ -20,8 +20,7 @@ require (
 	github.com/urfave/cli v1.20.0
 	github.com/vektah/dataloaden v0.2.0
 	github.com/vektah/gqlparser v1.1.2
-	golang.org/x/net v0.0.0-20180404174746-b3c676e531a6 // indirect
-	golang.org/x/tools v0.0.0-20190125232054-d66bd3c5d5a6
+	golang.org/x/tools v0.0.0-20190511041617-99f201b6807e
 	gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 // indirect
 	gopkg.in/yaml.v2 v2.2.2
 	sourcegraph.com/sourcegraph/appdash v0.0.0-20180110180208-2cc67fd64755

go.sum

@@ -52,10 +52,19 @@ github.com/vektah/dataloaden v0.2.0 h1:lhynDrG7c8mNLahboCo0Wq82tMjmu5yOUv2ds/tBm
 github.com/vektah/dataloaden v0.2.0/go.mod h1:vxM6NuRlgiR0M6wbVTJeKp9vQIs81ZMfCYO+4yq/jbE=
 github.com/vektah/gqlparser v1.1.2 h1:ZsyLGn7/7jDNI+y4SEhI4yAxRChlv15pUHMjijT+e68=
 github.com/vektah/gqlparser v1.1.2/go.mod h1:1ycwN7Ij5njmMkPPAOaRFY4rET2Enx7IkVv3vaXspKw=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
 golang.org/x/net v0.0.0-20180404174746-b3c676e531a6 h1:mge3qS/eMvcfyIAzTMOAy0XUzWG6Lk0N4M8zjuSmdco=
 golang.org/x/net v0.0.0-20180404174746-b3c676e531a6/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a h1:oWX7TPOiFAMXLq8o0ikBYfCJVlRHBcsciT5bXOrH628=
+golang.org/x/net v0.0.0-20190311183353-d8887717615a/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/tools v0.0.0-20190125232054-d66bd3c5d5a6 h1:iZgcI2DDp6zW5v9Z/5+f0NuqoxNdmzg4hivjk2WLXpY=
 golang.org/x/tools v0.0.0-20190125232054-d66bd3c5d5a6/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20190125232054-dbeab5af4b8d3204d444b78cafaba18a9a062a50/go.mod h1:LCzVGOaR6xXOjkQ3onu1FJEFr0SW1gC7cKk1uF8kGRs=
+golang.org/x/tools v0.0.0-20190511041617-99f201b6807e h1:wTxRxdzKt8fn3IQa3+kVlPJMxK2hJj2Orm+M2Mzw9eg=
+golang.org/x/tools v0.0.0-20190511041617-99f201b6807e/go.mod h1:RgjU9mgBXZiqYHBnxXauZ1Gv1EHHAz9KjViQ78xBX0Q=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=

internal/code/imports.go

@@ -2,53 +2,107 @@ package code
 
 import (
 	"errors"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"io/ioutil"
 	"path/filepath"
+	"regexp"
+	"strings"
 	"sync"
 
 	"golang.org/x/tools/go/packages"
 )
 
-var pathForDirCache = sync.Map{}
+var nameForPackageCache = sync.Map{}
 
-// ImportPathFromDir takes an *absolute* path and returns a golang import path for the package, and returns an error if it isn't on the gopath
-func ImportPathForDir(dir string) string {
-	if v, ok := pathForDirCache.Load(dir); ok {
-		return v.(string)
+var gopaths []string
+
+func init() {
+	gopaths = filepath.SplitList(build.Default.GOPATH)
+	for i, p := range gopaths {
+		gopaths[i] = filepath.ToSlash(filepath.Join(p, "src"))
 	}
+}
 
-	p, _ := packages.Load(&packages.Config{
-		Dir: dir,
-	}, ".")
+// NameForDir manually looks for package stanzas in files located in the given directory. This can be
+// much faster than having to consult go list, because we already know exactly where to look.
+func NameForDir(dir string) string {
+	dir, err := filepath.Abs(dir)
+	if err != nil {
+		return SanitizePackageName(filepath.Base(dir))
+	}
+	files, err := ioutil.ReadDir(dir)
+	if err != nil {
+		return SanitizePackageName(filepath.Base(dir))
+	}
+	fset := token.NewFileSet()
+	for _, file := range files {
+		if !strings.HasSuffix(strings.ToLower(file.Name()), ".go") {
+			continue
+		}
+
+		filename := filepath.Join(dir, file.Name())
+		if src, err := parser.ParseFile(fset, filename, nil, parser.PackageClauseOnly); err == nil {
+			return src.Name.Name
+		}
+	}
 
-	// If the dir dosent exist yet, keep walking up the directory tree trying to find a match
-	if len(p) != 1 {
-		parent, err := filepath.Abs(filepath.Join(dir, ".."))
+	return SanitizePackageName(filepath.Base(dir))
+}
+
+// ImportPathForDir takes a path and returns a golang import path for the package
+func ImportPathForDir(dir string) (res string) {
+	dir, err := filepath.Abs(dir)
+	if err != nil {
+		panic(err)
+	}
+	dir = filepath.ToSlash(dir)
+
+	modDir := dir
+	assumedPart := ""
+	for {
+		f, err := ioutil.ReadFile(filepath.Join(modDir, "/", "go.mod"))
+		if err == nil {
+			// found it, stop searching
+			return string(modregex.FindSubmatch(f)[1]) + assumedPart
+		}
+
+		assumedPart = "/" + filepath.Base(modDir) + assumedPart
+		modDir, err = filepath.Abs(filepath.Join(modDir, ".."))
 		if err != nil {
 			panic(err)
 		}
+
 		// Walked all the way to the root and didnt find anything :'(
-		if parent == dir {
-			return ""
+		if modDir == "/" {
+			break
 		}
-		return ImportPathForDir(parent) + "/" + filepath.Base(dir)
 	}
 
-	pathForDirCache.Store(dir, p[0].PkgPath)
+	for _, gopath := range gopaths {
+		if len(gopath) < len(dir) && strings.EqualFold(gopath, dir[0:len(gopath)]) {
+			return dir[len(gopath)+1:]
+		}
+	}
 
-	return p[0].PkgPath
+	return ""
 }
 
-var nameForPackageCache = sync.Map{}
+var modregex = regexp.MustCompile("module (.*)\n")
 
+// NameForPackage returns the package name for a given import path. This can be really slow.
 func NameForPackage(importPath string) string {
 	if importPath == "" {
 		panic(errors.New("import path can not be empty"))
 	}
 	if v, ok := nameForPackageCache.Load(importPath); ok {
 		return v.(string)
 	}
-	importPath = QualifyPackagePath(importPath)
-	p, _ := packages.Load(nil, importPath)
+	//importPath = QualifyPackagePath(importPath)
+	p, _ := packages.Load(&packages.Config{
+		Mode: packages.NeedName,
+	}, importPath)
 
 	if len(p) != 1 || p[0].Name == "" {
 		return SanitizePackageName(filepath.Base(importPath))

internal/code/imports_test.go

@@ -30,3 +30,13 @@ func TestNameForPackage(t *testing.T) {
 	assert.Equal(t, "docs", NameForPackage("github.com/99designs/gqlgen/docs"))
 	assert.Equal(t, "github_com", NameForPackage("github.com"))
 }
+
+func TestNameForDir(t *testing.T) {
+	wd, err := os.Getwd()
+	require.NoError(t, err)
+
+	assert.Equal(t, "tmp", NameForDir("/tmp"))
+	assert.Equal(t, "code", NameForDir(wd))
+	assert.Equal(t, "internal", NameForDir(wd+"/.."))
+	assert.Equal(t, "main", NameForDir(wd+"/../.."))
+}

plugin/stubgen/stubs.go

@@ -34,8 +34,11 @@ func (m *Plugin) MutateConfig(cfg *config.Config) error {
 }
 
 func (m *Plugin) GenerateCode(data *codegen.Data) error {
-	pkgPath := code.ImportPathForDir(filepath.Dir(m.filename))
-	pkgName := code.NameForPackage(pkgPath)
+	abs, err := filepath.Abs(m.filename)
+	if err != nil {
+		return err
+	}
+	pkgName := code.NameForDir(filepath.Dir(abs))
 
 	return templates.Render(templates.Options{
 		PackageName: pkgName,