BUILD file generation

[alexeagle]

Like https://github.com/bazelbuild/rules_go/tree/master/go/tools/gazelle

we should be able to generate/maintain BUILD files automatically from TypeScript sources.
We do this internally at google.

[dgoldstein0]

if this were open sourced, I would be interested in using it here at Dropbox.

[ashi009]

Any updates on this? Would love to contribute on this if there is a design doc shared publicly.

AFAIK, Gazelle is aiming to provide build file generation for other languages as well, and the implementation is almost language-agnostic already.

EDIT: gazelle 0.16 is now released with custom language support

[alexeagle]

ts_auto_deps is now released, which has very minimal support for BUILD file generation.
Will move this to rules_nodejs - @Globegitter has a gazelle-based TS BUILD file generator but I'd like to see this reconciled with the library code in ts_auto_deps (both are written in Go so it should be possible)

[Globegitter]

I actually just added basic ts_library support now to the build file generator, as well as for babel_library. It does not add any test rules yet for .spec.ts files but that would also not be too difficult. In any case, I agree reconciliation would be good. I wonder how the two generators differ and what the one is missing from the other. Probably good to set a little test project up at some point. Or I might even try to use the auto-generators on all the examples/tests in this repo. Might be a decent test scenario.

[codebreach]

It seems that ts_auto_deps was removed in bazelbuild/rules_typescript@09f0469

is there a story for this moving forward?

asking as we are trying to move a relatively large project (300K LOC across 3K+ components) to bazel and were wondering if there was a tool to generate the first pass of BUILD files.

[vpanta]

As someone who recently left Google, I was just about to file a FR for taze to be open sourced XD
I was very sad to see we never got it out to the world :(

I guess this is the right place to add my "please may we get it", cause honestly taze made everything so simple...

[alexeagle]

Hi @vpanta welcome to xoogler status! Let me dump a bit of my current thinking on this.

There are a few partial attempts at this. I recently wrote a generator for ts_project and pkg_npm in https://github.com/stackb/bzl-configure. @mattem has made a bunch of progress on https://github.com/Evertz/bzlgen. @Globegitter mentions his tooling up the thread. I think we'll continue to have partial solutions contributed by lots of people without much coordination between them.

There are a bunch of ways you might want to setup your repo. taze was based on a single opinion and a single rule (ts_library). In the wild, one team might want to generate pkg_npm from every package.json while another team doesn't want to check in any package.json files. One team might use a variant of the toolchain with ts_project mixed with babel. I think we'll have increasing fragmentation of how you might want to generate BUILD files.

Finally, you have the polyglot story. You need tooling written in the same language, for example ts_project generation needs to use the typescript library (unlike taze, it asks TypeScript itself for what are the srcs in the project, so it can't be in pure Go). So I don't think there can be one tool either.

All of this leads me to think that we need a loose coupling and powerful meta-configuration facility, with possibly several tools coordinating work.

My current favorite loosely-considered proposal: Gazelle as the coordinator, with a plugin for typescript that spawns a nodejs subprocess to do the actual work. That subprocess has a generalized API for passing stdin/arguments and producing buildozer commands on stdout. In addition to running that tool under gazelle, you can also run it standalone with the @bazel/buildozer dependency to apply the edits itself. Then a separate competing coordinator that takes a richer DSL for configuration, allowing you to say "all the tsconfig.json files under this directory should be turned into ts_project using that tool, plus any foo.bar files should have my_custom_rule generated for them"

If you have any time to dig in, happy to think through this some more.

[mattem]

I was having the same thoughts around using the plugins for Gazelle in bzlgen (Evertz/bzlgen#50) as there are specific typescript libraries and implementations that make it easier to resolve deps for TS, especially when generating for ng_module (or a variant that needs the angular assets).

I think with all of these tools, they are going to be very opinionated depending on where they originated (bzlgen expects Evertz' way of doing Angular folder layouts for example, and lacks support for ts_project). Having said that, I'm happy to drive it in the right direction for this, my eventual goal is for our internal version to go away and I just have to maintain one thing (might as well be the OSS one).

[purkhusid]

Is it currently possible to create a Gazelle extension that is not purely Go? I was thinking about doing some buildfile generation but hit a wall when trying to figure out how I would let my gazelle extension call a node process that would take care of parsing the files.

[alexeagle]

With @achew22 and @mrmeku I started this "rosetta" plugin for gazelle that adapts the API to work with any subprocess
https://github.com/alexeagle/bazel-gazelle
The plan is to let you write gazelle plugins in any language.

[github-actions]

This issue has been automatically marked as stale because it has not had any activity for 90 days. It will be closed if no further activity occurs in two weeks. Collaborators can add a "cleanup" or "need: discussion" label to keep it open indefinitely. Thanks for your contributions to rules_nodejs!

[github-actions]

This issue has been automatically marked as stale because it has not had any activity for 90 days. It will be closed if no further activity occurs in two weeks. Collaborators can add a "cleanup" or "need: discussion" label to keep it open indefinitely. Thanks for your contributions to rules_nodejs!

[github-actions]

This issue was automatically closed because it went two weeks without a reply since it was labeled "Can Close?"

[andy-zhou]

What's the preferred way of making a build_cleaner like utility today? I noticed that @Globegitter's repo has been archived.