cmd/go: package modules into mod format for upload

[doddi]

Currently, there is no mechanism to package the content of a module project into a zip that is compatible with the go mod system

This PR adds a go mod pack command that does just that and a go mod push to then upload the generated zip to a hosted repository

Fixes #33312

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This PR (HEAD: 82637ab) has been imported to Gerrit for code review.

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This PR (HEAD: f69f202) has been imported to Gerrit for code review.

Please visit https://go-review.googlesource.com/c/go/+/193557 to see it.

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Message from Bryan C. Mills:

Patch Set 3:

We should discuss the API on the linked issue before we get into too much detail on the implementation. (For example, it's not obvious to me that this should be built in to the go command — it could almost as easily be a standalone binary in x/tools.)

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Message from Mark Dodgson:

Patch Set 3:

Patch Set 3:

We should discuss the API on the linked issue before we get into too much detail on the implementation. (For example, it's not obvious to me that this should be built in to the go command — it could almost as easily be a standalone binary in x/tools.)

How should I progress with this? (apologies never contributed in this way before)
Should I just wait until further discussion has been had with other peers on the way forward?

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Message from Bryan C. Mills:

Patch Set 3:

Patch Set 3:

Patch Set 3:

We should discuss the API on the linked issue before we get into too much detail on the implementation. (For example, it's not obvious to me that this should be built in to the go command — it could almost as easily be a standalone binary in x/tools.)

How should I progress with this? (apologies never contributed in this way before)
Should I just wait until further discussion has been had with other peers on the way forward?

Not sure. I think Jay is planning to look at this for the gorelease tool, so probably he'll have some ideas about where to put it.

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Message from Jay Conrod:

Patch Set 3:

How should I progress with this? (apologies never contributed in this way before)
Should I just wait until further discussion has been had with other peers on the way forward?

Not sure. I think Jay is planning to look at this for the gorelease tool, so probably he'll have some ideas about where to put it.

I'm working on a CL that will add a package golang.org/x/mod/archive with the functions:

func CreateFromDir(w io.Writer, m module.Version, dir string) error
func CreateFromZip(w io.Writer, m module.Version, zipPath, subdir string) error
func Unzip(dir string, m module.Version, zipPath string) error

Once that's merged and we've verified it produces the same zips as the go command currently does, we can delete that functionality from the go command and use the x/mod packages.

It will be trivial to write "pack" and "push" tools around that. I may include a "pack" tool, but I expect that the "push" workflow will need to be customized a bit for every server, so it's probably best if people write their own tools for that.

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Message from Go Bot:

Patch Set 1:

Congratulations on opening your first change. Thank you for your contribution!

Next steps:
Within the next week or so, a maintainer will review your change and provide
feedback. See https://golang.org/doc/contribute.html#review for more info and
tips to get your patch through code review.

Most changes in the Go project go through a few rounds of revision. This can be
surprising to people new to the project. The careful, iterative review process
is our way of helping mentor contributors and ensuring that their contributions
have a lasting impact.

During May-July and Nov-Jan the Go project is in a code freeze, during which
little code gets reviewed or merged. If a reviewer responds with a comment like
R=go1.11, it means that this CL will be reviewed as part of the next development
cycle. See https://golang.org/s/release for more details.

---

Please don’t reply on this GitHub thread. Visit golang.org/cl/193557.
After addressing review feedback, remember to publish your drafts!