windows support

[peakschris]

Most features are working

Adds:

• Windows support
• Use tar from tar.bzl directly instead of via aspect_lib
• All rules upgraded to use runfiles libs; so --enable_runfiles not required on Windows
• Bump tar aspect_lib and crane (for required windows fixes)
• Bump container_structure_test (for windows; bump to latest)
• Windows tests pass and are enabled in CI

Limitations

• oci_load rules don't work - RUNFILES_DIR doesn't seem to be set - e.g. case11_test
• have not validated that this works to build native windows containers

Fixes:

• _maybe_wrap_launcher_for_windows selects wrapper based on target platform #420
• v2.0.0 on Windows #714
• Bazel warning regarding deprecated @@bazel_tools//src/conditions:host_windows_x64_constraint being used by oci_image #819
• Building oci_image on Windows (Git Bash) - Results in "No matching toolchains found for types @@aspect_bazel_lib~//lib:zstd_toolchain_type" #716

Other relevant PRs

• bsdtar: Allow @filename to have CRLF endings libarchive/libarchive#2717
• windows support buildbuddy-io/bazel_env.bzl#56
• crlf & better cli diagnostics aspect-build/bsdtar-prebuilt#19
• feat: fix zstd_toolchain and enable root tests on Windows bazel-lib#1137

Test results:
bazel test //... --action_env=PATH - 36 pass and 14 skipped
bazel test //... --action_env=PATH --enable_runfiles - 36 pass and 14 skipped

[peakschris]

edit: no .bazelrc.user required

[aspect-workflows]

Test

All tests were cache hits

49 tests (100.0%) were fully cached saving 25s.

[thesayyn]

This looks great, i am okay with landing this as is, if you could selectively disable tests that doesn't work windows.

[peakschris]

@thesayyn I now have bsdtar fixed on Windows; thanks to @alexeagle for pushing the patch through all the repos. rules_oci now looks like it is working pretty well.

• There is the docs update to do; I can't do this as the docs update tooling doesn't work on Windows. Would you be able to push a commit to fix the docs?
• Would it be possible to enable Windows CI?

Thanks!

[peakschris]

@thesayyn ping

[peakschris]

@thesayyn This is ready to go - except the docs update which I can't run from windows. Please would you do this and advise on next steps? Thank you!

cc @alexeagle @fmeum

[peakschris]

@thesayyn I fixed the bazel-lib docs macros whilst I was waiting :-) so these docs files are now updated and this is ready to go.

[peakschris]

@fmeum I made some fixes; could you please trigger CI again?

[kcking]

@thesayyn any chance you can take another look at this PR? :)

[thesayyn]

This is looking closer. There seems to be some bad diff from formatters and feature additions which i'd like to address in a separate PR.

[peakschris]

@thesayyn Thanks for your review; I've addressed all your comments; moved unrelated features out; rebased to latest

[thesayyn]

Looking great, a few small changes.

[thesayyn]

I'll merge this once the windows cfg selection is fixed.

[thesayyn]

@peakschris it would be nice to get windows CI back. do you mind adding that to the matrix? Also bcr presubmit will need to change to test for windows there.

[peakschris]

@peakschris it would be nice to get windows CI back. do you mind adding that to the matrix? Also bcr presubmit will need to change to test for windows there.

I've added to bcr presubmit; happy to make a change to github workflows if you can guide me - I'm not familiar with this and superficially it looks like windows is already configured

[peakschris]

@thesayyn trying to get windows CI added & not hanging by following pattern from bazel-lib; can you give me rights to trigger/retrigger the workflow?

[peakschris]

@thesayyn I could use some advice. Building case4_transition with Bazel 8.3.1 or 8.4.1:

# Case 4: Transition an oci_image and feed to oci_tarball
oci_image(
    name = "case4",
    architecture = "arm64",
    os = "linux",
)

platform_transition_filegroup(
    name = "case4_transition",
    srcs = [":case4"],
    target_platform = "//examples:linux_arm64",
)

results in ctx.toolchains["@bazel_tools//tools/sh:toolchain_type"].path returning /bin/bash instead of C:\msys64\usr\bin\bash.exe as set in BAZEL_SH envvar. This results in the bat wrappers generated for windows failing with invalid path.

Is there any way to get the @bazel_tools//tools/sh:toolchain_type without it being interfered by the transition?

This is only an issue with bazel 8; bazel 7.6.1 returns the windows bash.exe

Thanks! Chris

[peakschris]

bazelbuild/bazel#27310

[peakschris]

@thesayyn @mostynb I'm going to give up on this for now; I'm unable to get all the tests green for the same reasons that this PR struggled: #842

Upgrading to a version of bazel_lib that contains a tar that works on Windows requires us to drop support for modules under bazel 6; as @mostynb argues we could consider dropping bazel 6 completely.

If you can get #842 merged then I can have another go with this.

[thesayyn]

Thanks, I'll see how i can help.

[thesayyn]

Hmm, why this is needed? i thought we simply dropped this requirement with some release of bazel_lib.

[peakschris]

I'm not sure if it was needed; I was seeing strange errors relate to resolving zstd toolchain so I pasted it in from bazel_lib release notes.

[peakschris]

Thanks, I'll see how i can help.

Thank you!

[mostynb]

Here's an attempt to upgrade CI to test bazel 7 and 8: #854