ci: align with bazel-contrib/rules-template and refactor e2e tests

.bazelrc

@@ -1,4 +1,23 @@
+# Bazel settings that apply to this repository.
+# Take care to document any settings that you expect users to apply.
+# Settings that apply only to CI are in .github/workflows/ci.bazelrc
+
+# Required until this is the default; expected in Bazel 7
 common --enable_bzlmod
 
+# Don’t want to push a rules author to update their deps if not needed.
+# https://bazel.build/reference/command-line-reference#flag--check_direct_dependencies
+# https://bazelbuild.slack.com/archives/C014RARENH0/p1691158021917459?thread_ts=1691156601.420349&cid=C014RARENH0
+common --check_direct_dependencies=off
+
+# Load any settings specific to the current user.
+# .bazelrc.user should appear in .gitignore so that settings are not shared with team members
+# This needs to be last statement in this
+# config, as the user configuration should be able to overwrite flags from this file.
+# See https://docs.bazel.build/versions/master/best-practices.html#bazelrc
+# (Note that we use .bazelrc.user so the file appears next to .bazelrc in directory listing,
+# rather than user.bazelrc as suggested in the Bazel docs)
 try-import %workspace%/.bazelrc.user
+
+# Load any settings specific to ci pipelines.
 try-import %workspace%/.bazelrc.ci

.gitattributes

@@ -1,6 +1,11 @@
+# In code review, collapse generated files
+docs/*.md linguist-generated=true
+
+#################################
 # Configuration for 'git archive'
-# see https://git-scm.com/docs/git-archive/2.40.0#ATTRIBUTES
-# Don't include examples in the distribution artifact, just to reduce size
-.github/ export-ignore
-examples/ export-ignore
-tests/smoke_workspace/ export-ignore
+# See https://git-scm.com/docs/git-archive#ATTRIBUTES
+
+# Don't include examples in the distribution artifact, to reduce size.
+# You may want to add additional exclusions for folders or files that users don't need.
+examples export-ignore
+.github export-ignore

.github/workflows/BUILD.bazel

@@ -0,0 +1,8 @@
+load("@buildifier_prebuilt//:rules.bzl", "buildifier")
+
+buildifier(
+    name = "buildifier.check",
+    exclude_patterns = ["./.git/*"],
+    lint_mode = "warn",
+    mode = "diff",
+)

.github/workflows/bazel.yaml

@@ -0,0 +1,170 @@
+# This is a modified version of upstream.
+# see: https://github.com/bazel-contrib/.github/issues/21
+#
+# Reusable workflow that can be referenced by repositories in their .github/workflows/ci.yaml.
+# See example usage in https://github.com/bazel-contrib/rules-template/blob/main/.github/workflows/ci.yaml
+#
+# This assumes the repo calling the workflow has at least these files:
+# - .github/workflows/ci.bazelrc
+# - .bazelrc
+#
+# This workflow uses https://github.com/bazel-contrib/setup-bazel to prepare the cache folders.
+# Caching may be disabled by setting `mount_bazel_caches` to false.
+
+on:
+  # Make this workflow reusable, see
+  # https://github.blog/2022-02-10-using-reusable-workflows-github-actions
+  workflow_call:
+    inputs:
+      folders:
+        required: true
+        # JSON is needed because list is not supported:
+        # https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#onworkflow_callinputsinput_idtype
+        description: |
+          JSON-formatted array of folders to run 'bazel test' in.
+          For example, '[".", "e2e/smoke"]'
+        type: string
+      bazelversions:
+        description: |
+          JSON-formatted array of bazelversion to run 'bazel test' for.
+
+          The version from .bazelversion is used unless this option is set.
+
+          For example, '["7.x", "8.0.0rc1"]'
+        type: string
+        default: "[]"
+      exclude:
+        description: |
+          JSON-formatted array of exclusions to the generated matrix of tests.
+
+          By default, we don't test non-linux with Bazel 8 to minimize macOS and Windows minutes
+          since they are billed at 10X and 2X respectively:
+          https://docs.github.com/en/billing/managing-billing-for-github-actions/about-billing-for-github-actions#included-storage-and-minutes
+
+          Note: independent of this setting, we don't create MacOS/Windows matrix entries for pull requests
+          unless they come from a specially-named branch. See logic below.
+        type: string
+        default: |
+          [
+            {"bazelversion": "8.0.0rc1", "os": "macos-latest"},
+            {"bazelversion": "8.0.0rc1", "os": "windows-latest"}
+          ]
+      exclude_windows:
+        description: Don't run any tests on Windows
+        type: boolean
+      bazel_test_command:
+        default: "bazel test //..."
+        description: |
+          Bazel test command that may be overridden to set custom flags and targets.
+          The `--enable_bzlmod={true,false}`, `--disk_cache=~/.cache/bazel-disk-cache`,
+          and `--repository_cache=~/.cache/bazel-repository-cache` flags are
+          automatically appended to the command.
+        type: string
+      mount_bazel_caches:
+        default: true
+        description: |
+          Whether to enable caching in the bazel-contrib/setup-bazel action.
+        type: boolean
+
+jobs:
+  # matrix-prep-* steps generate JSON used to create a dynamic actions matrix.
+  # Inspired from
+  # https://stackoverflow.com/questions/65384420/how-to-make-a-github-action-matrix-element-conditional
+
+  matrix-prep-os:
+    # Prepares the 'os' axis of the test matrix, to reduce costs since GitHub hosted runners cost more on some platforms.
+    # https://docs.github.com/en/billing/managing-billing-for-github-actions/about-billing-for-github-actions#included-storage-and-minutes
+    runs-on: ubuntu-latest
+    steps:
+      - id: linux
+        run: echo "os=ubuntu-latest" >> $GITHUB_OUTPUT
+      - id: windows
+        run: echo "os=windows-latest" >> $GITHUB_OUTPUT
+        # Only run on main branch (or PR branches that contain 'windows') to minimize Windows minutes (billed at 2X)
+        if: (github.ref == 'refs/heads/main' || contains(github.head_ref, 'windows')) && !inputs.exclude_windows
+      - id: macos
+        run: echo "os=macos-latest" >> $GITHUB_OUTPUT
+        # Only run on main branch (or PR branches that contain 'macos') to minimize macOS minutes (billed at 10X)
+        if: github.ref == 'refs/heads/main' || contains(github.head_ref, 'macos')
+    outputs:
+      # Will look like ["ubuntu-latest", "windows-latest", "macos-latest"]
+      os: ${{ toJSON(steps.*.outputs.os) }}
+
+  matrix-prep-bazelversion:
+    # Prepares the 'bazelversion' axis of the test matrix
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      # NB: we assume this is Bazel 7
+      - id: bazel_from_bazelversion
+        if: inputs.bazelversions == '[]'
+        run: echo "bazelversion=$(head -n 1 .bazelversion)" >> $GITHUB_OUTPUT
+    outputs:
+      # Will look like ["<version from .bazelversion>"]
+      bazelversions: ${{ toJSON(steps.*.outputs.bazelversion) }}
+
+  test:
+    # The type of runner that the job will run on
+    runs-on: ${{ matrix.os }}
+
+    needs:
+      - matrix-prep-bazelversion
+      - matrix-prep-os
+
+    # Run bazel test in each workspace with each version of Bazel supported
+    strategy:
+      fail-fast: false
+      matrix:
+        os: ${{ fromJSON(needs.matrix-prep-os.outputs.os) }}
+        bazelversion:
+          [
+            "${{ fromJSON(needs.matrix-prep-bazelversion.outputs.bazelversions) }}",
+            "${{ fromJSON(inputs.bazelversions) }}",
+          ]
+        folder: ${{ fromJSON(inputs.folders) }}
+        bzlmodEnabled: [true, false]
+        exclude: ${{ fromJSON(inputs.exclude) }}
+
+    env:
+      USE_BAZEL_VERSION: ${{matrix.bazelversion}}
+
+    # Steps represent a sequence of tasks that will be executed as part of the job
+    steps:
+      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+      - uses: actions/checkout@v4
+
+      - uses: bazel-contrib/setup-bazel@0.8.0
+        with:
+          repository-cache: ${{ inputs.mount_bazel_caches }}
+          bazelrc: common --announce_rc --color=yes --enable_bzlmod=${{ matrix.bzlmodEnabled }} --enable_workspace=${{ ! matrix.bzlmodEnabled }}
+
+      - name: Check Bazel version
+        working-directory: ${{ matrix.folder }}
+        run: bazel version
+
+      - name: Check for test.sh
+        # Checks for the existence of test.sh in the folder. Downstream steps can use
+        # steps.has_test_sh.outputs.files_exists as a conditional.
+        id: has_test_sh
+        uses: andstor/file-existence-action@v3
+        with:
+          files: "${{ matrix.folder }}/test.sh"
+
+      # See https://github.com/bazel-contrib/publish-to-bcr#including-patches
+      - name: verify bcr patches
+        if: matrix.bzlmodEnabled && hashFiles('.bcr/patches/*.patch') != '' && ! startsWith(matrix.os, 'windows')
+        run: patch --dry-run -p1 < .bcr/patches/*.patch
+
+      - name: Test
+        working-directory: ${{ matrix.folder }}
+        run: ${{ inputs.bazel_test_command }}
+
+      - name: Run ./test.sh
+        # Run if there is a test.sh file in the folder
+        # Don't run integration tests on Windows since they are bash scripts and Windows runs Powershell
+        if: steps.has_test_sh.outputs.files_exists == 'true' && ! startsWith(matrix.os, 'windows')
+        working-directory: ${{ matrix.folder }}
+        shell: bash
+        # Run the script potentially setting BZLMOD_FLAG=--enable_bzlmod. All test.sh
+        # scripts that run bazel directly should make use of this variable.
+        run: BZLMOD_FLAG=--enable_bzlmod=${{ matrix.bzlmodEnabled }} ./test.sh

.github/workflows/buildifier.yaml

@@ -0,0 +1,19 @@
+name: Buildifier
+
+# Controls when the action will run.
+on:
+  # Triggers the workflow on push or pull request events but only for the main branch
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: buildifier
+        run: bazel run --enable_bzlmod //.github/workflows:buildifier.check

.github/workflows/ci.bazelrc

@@ -4,8 +4,10 @@
 # Debug where options came from
 build --announce_rc
 # This directory is configured in GitHub actions to be persisted between runs.
+# We do not enable the repository cache to cache downloaded external artifacts
+# as these are generally faster to download again than to fetch them from the
+# GitHub actions cache.
 build --disk_cache=~/.cache/bazel
-build --repository_cache=~/.cache/bazel-repo
 # Don't rely on test logs being easily accessible from the test runner,
 # though it makes the log noisier.
 test --test_output=errors