Initial spec lint action commit (#172) (#190)

* Initial spec-cleaner commit for CBL-Mariner

* Add cgmanifest.json file for GitHub workflows folder

* Set continue-on-error to true for a trial period

.github/workflows/cgmanifest.json

@@ -0,0 +1,14 @@
+{
+    "Registrations": [
+      {
+        "Component": {
+          "Type": "git",
+          "Git": {
+            "RepositoryUrl": "https://github.com/rpm-software-management/spec-cleaner",
+            "CommitHash": "f24cd83e5e2775b061696d4fd7fcf47f63514b50"
+          }
+        }
+      }
+    ],
+    "Version": 1
+  }

.github/workflows/lint-specs.yml

@@ -0,0 +1,95 @@
+name: Spec Linting
+
+on:
+  push:
+    paths:
+      - '**.spec'
+    branches: [main, dev, 1.0*]
+  pull_request:
+    paths:
+      - '**.spec'
+    branches: [main, dev, 1.0*]
+
+jobs:
+  spec-lint:
+    runs-on: ubuntu-latest
+
+    steps:
+      # Checkout the branch of our repo that triggered this action
+      - name: Workflow trigger checkout
+        uses: actions/checkout@v2
+
+      - name: Get base commit for PRs
+        if: ${{ github.event_name == 'pull_request' }}
+        run: |
+          git fetch origin ${{ github.base_ref }}
+          echo "base_sha=$(git rev-parse origin/${{ github.base_ref }})" >> $GITHUB_ENV 
+          echo "Merging ${{ github.sha }} into ${{ github.base_ref }}"
+
+      - name: Get base commit for Pushes
+        if: ${{ github.event_name == 'push' }}
+        run: |
+          git fetch origin ${{ github.event.before }}
+          echo "base_sha=${{ github.event.before }}" >> $GITHUB_ENV 
+          echo "Merging ${{ github.sha }} into ${{ github.event.before }}"
+
+      - name: Get the changed files
+        run: |
+          echo "Files changed: '$(git diff-tree --no-commit-id --name-only -r ${{ env.base_sha }} ${{ github.sha }})'"
+          changed_specs=$(git diff-tree --no-commit-id --name-only -r ${{ env.base_sha }} ${{ github.sha }} | { grep "\.spec$" || test $? = 1; })
+          echo "Files to validate: '${changed_specs}'"
+          echo "updated-specs=$(echo ${changed_specs})" >> $GITHUB_ENV
+
+      - name: Main branch checkout 
+        uses: actions/checkout@v2
+        with:
+          ref: 'main'
+          path: 'main-checkout'
+
+      # Our linter is based on the spec-cleaner tool from the folks at openSUSE
+      # We apply a patch to modify it for CBL-Mariner's needs
+      - name: spec-cleaner checkout
+        uses: actions/checkout@v2
+        with:
+          repository: 'rpm-software-management/spec-cleaner'
+          ref: 'spec-cleaner-1.2.0'
+          path: 'spec-cleaner'
+
+      # For consistency, we use the same major/minor version of Python that CBL-Mariner ships
+      - name: Setup Python 3.7
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.7
+        
+      # We take our version of the linting tool from the master branch to ensure rules
+      # are consistent across all branches
+      - name: Patch spec-cleaner with Mariner-specific lints
+        run: |
+          pushd spec-cleaner
+          git apply ../main-checkout/.github/workflows/mariner-spec-cleaner.patch
+          popd
+
+      - name: Install patched spec-cleaner
+        run: |
+          python -m pip install --upgrade pip
+          pip install -e ./spec-cleaner
+      
+      # Set continue-on-error to true if we're blocking too many PRs here
+      # We don't want this tool to have a low signal-to-noise ratio
+      - name: Lint changed spec files
+        continue-on-error: true
+        run: |
+          mkdir -p linted_specs
+          spec-cleaner -o linted_specs ${{ env.updated-specs }}
+          [ -n "$(ls -A linted_specs)" ] \
+          && echo "Specs are not correctly formatted." \
+          && echo "The linted_specs artifact contains linted versions of the specs you're checking in." \
+          && echo "Please properly format your specs according to that output before merging." \
+          && exit 1
+
+      - uses: actions/upload-artifact@v2
+        with:
+          name: linted_specs
+          path: linted_specs
+          if-no-files-found: ignore
+          if: always()