Dep: Ensure -vendor-only ignores -v

[lwc]

Thanks so much for adding -vendor-only - this is a much needed feature for guaranteeing reliable CI builds 👍

What version of Go (go version) and dep (git describe --tags) are you using?

$ go version
go version go1.8.1 darwin/amd64

$ git describe --tags
v0.3.0-19-g52ed251

What dep command did you run?

Looks like -vendor-only doesn't have a verbose mode:

$ dep ensure -vendor-only
$ dep ensure -v -vendor-only
$

What did you expect to see?

Some kind of indication that something is happening - a list of what is getting installed?

What did you see instead?

Nada! 😁

[sdboyer]

hi, welcome! thanks for the issue 😄

Thanks so much for adding -vendor-only - this is a much needed feature for guaranteeing reliable CI builds 👍

🎉🎉 - sorry it took so long!

Some kind of indication that something is happening - a list of what is getting installed?

HAH! this literally never even occurred to me during the design.

-vendor-only basically just skips the first half of ensure's work, jumping right to the part where we write vendor/. that segment has never produced any feedback, which has (i guess) been mostly fine, but it's particularly obvious now that -vendor-only allows you to skip ahead.

achieving this probably wouldn't be too awful. i don't think it would be terribly useful right now, as we always and unconditionally regenerate vendor/ in its entirety on every dep ensure. however, we're well on our way - #959 - to introducing a system that will allow us to do only partial writes to vendor, at which point i think such feedback is likely to become much more useful.

for now, we should take the same basic approach as with gps.SolveParameters - optionally inject a logger into gps.WriteDepTree() (the func that populates vendor/), and incrementally report progress to that. SafeWriter.Write() will also then need to take a logger argument, the presence of which it can use as an indication that it should report its own progress.

@carolynvs you've worked on those parts a bunch - does that seem sane? could that interleave sanely with existing dep init output?

[ebati]

If you can assist me by answering questions below I can work on this issue.

• We can create a global no-op logger and every function can use it. If verbose flag is set _defaultlogger_ can be set to ctx.Out.
• logger can be set optionally after creating SafeWriter. That way no signature change is needed in the public api ( gps.writeDepTree also needs signature change but it is an internal package ) .
• logger can be sent optionally to sw.Write and from there to gps.writeDepTree
• with dry-run and verbose selected together sw.PrintPreparedActions can be called in addition to vendor would be populated log.

[sdboyer]

If you can assist me by answering questions below I can work on this issue.

awesome, sure!

We can create a global no-op logger and every function can use it.

nope nope nope, no globals 😜

logger can be set optionally after creating SafeWriter. That way no signature change is needed in the public api

we're not worrying about public API stability yet, as we're pre-1.0.0. so it'll be fine to inject the desired *log.Logger (passed from *dep.Ctx) as a new parameter to sw.Write().

with dry-run and verbose selected together sw.PrintPreparedActions can be called in addition to vendor would be populated log.

hmm - we may actually need to make dry run a more explicit concept for SafeWriter, as we're probably going to need to pass that flag down to gps.WriteDepTree() as well.

[carolynvs]

dep init doesn't write until the very end, so it should play just fine with the existing output.