code-quality-check.yml

name: Python

on:
  pull_request:

jobs:
  code-quality-check:
    name: Check Code Quality
    runs-on: ubuntu-latest

    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Set up Python
        uses: actions/setup-python@v5
        with:
          python-version: '3.13'

      - name: Install dependencies
        run: |
          pip install flake8 black

      - name: Run black and generate diff
        id: black_check
        run: |
          echo "Running black in check mode with diff output..."
          black --check --diff --line-length 99 . > formatting.diff || true

          if [ -s formatting.diff ]; then
            echo "Formatting issues detected:"
            cat formatting.diff
            echo "black_failed=true" >> $GITHUB_OUTPUT
          else
            echo "No formatting issues found."
          fi

      - name: Upload formatting.diff
        if: steps.black_check.outputs.black_failed == 'true'
        uses: actions/upload-artifact@v4
        with:
          name: python-formatting-diff
          path: formatting.diff

      - name: Detect changed Python files
        id: detect_changes
        run: |
          PR_NUMBER="${{ github.event.pull_request.number }}"
          REPO="${{ github.repository }}"

          # Fetch PR files and filter out removed files (only keep added, modified, renamed)
          curl -s -H "Authorization: Bearer ${{ secrets.GITHUB_TOKEN }}" \
            "https://api.github.com/repos/${REPO}/pulls/${PR_NUMBER}/files" \
            | jq -r '.[] | select(.status != "removed") | .filename' > all_files.txt

          grep '\.py$' all_files.txt > changed_files.txt || true

          if [[ ! -s changed_files.txt ]]; then
            echo "No Python files changed."
            echo "SKIP=true" >> $GITHUB_ENV
          else
            echo "SKIP=false" >> $GITHUB_ENV
            echo "CHANGED=$(cat changed_files.txt | xargs)" >> $GITHUB_ENV
          fi

      - name: Run Flake8 on changed files
        if: env.SKIP == 'false'
        run: |
          echo "Running flake8 on: $CHANGED"
          flake8 $CHANGED > flake8_output.txt || true

      - name: Format Flake8 results as PR comment
        if: env.SKIP == 'false'
        run: |
          python3 <<'EOF' > flake8_summary.md
          import os

          try:
              with open("flake8_output.txt") as f:
                lines = f.read().splitlines()
              
          except FileNotFoundError:
              lines = []

          print("### 🧹 Python Code Quality Check\n")
          run_url = f"https://github.com/{os.environ['GITHUB_REPOSITORY']}/actions/runs/{os.environ['GITHUB_RUN_ID']}"

          if not lines:
              print("✅ No issues found in Python Files.")
              issue_present = False
          else:
              issue_present = True
              print("⚠️ **Flake8 has detected issues, please fix the issues before merging:**")
              print(f"\n📎 [Download full report from workflow artifacts]({run_url}).")  
              print()
              print("📌 _Only Python files changed in this PR were checked._")
              
          slab_doc = f"https://fivetran.slab.com/posts/connector-sdk-examples-pr-policy-and-python-coding-standards-yzr9ggss#hb2vk-linting"
          print(f"\n🔍 [See how this check works]({slab_doc})")
          print("\n_This comment is auto-updated with every commit._")

          # Export environment variable
          with open(os.environ["GITHUB_ENV"], "a") as envf:
              envf.write(f"FLAKE8_ISSUE_PRESENT={'true' if issue_present else 'false'}\n")
              envf.write(f"RUN_URL={run_url}\n")
          EOF

      - name: Upload full report
        if: env.FLAKE8_ISSUE_PRESENT == 'true'
        uses: actions/upload-artifact@v4
        with:
          name: python-code-quality-report
          path: flake8_output.txt

      - name: Find existing comment
        uses: peter-evans/find-comment@v4
        id: find
        with:
          issue-number: ${{ github.event.pull_request.number }}
          comment-author: github-actions[bot]
          body-includes: "### 🧹 Python Code Quality Check"

      - name: Create or update PR comment
        if: env.SKIP == 'false'
        continue-on-error: true
        uses: peter-evans/create-or-update-comment@v4
        with:
          comment-id: ${{ steps.find.outputs.comment-id }}
          issue-number: ${{ github.event.pull_request.number }}
          body-path: flake8_summary.md
          edit-mode: replace

      - name: Fail if both black and flake8 failed
        if: steps.black_check.outputs.black_failed == 'true' && env.FLAKE8_ISSUE_PRESENT == 'true'
        run: |
          echo "Python formatting check failed. See formatting.diff artifact for details."
          echo "To fix the error(s) run the command below from the root of the repo and commit the changes:"
          echo "./.github/scripts/fix-python-formatting.sh"
          echo "We also detected Linting Issues in Python files. Please fix them before merging."
          echo "Download the full report from here: $RUN_URL"
          exit 1

      - name: Fail if only black failed
        if: steps.black_check.outputs.black_failed == 'true' && env.FLAKE8_ISSUE_PRESENT != 'true'
        run: |
          echo "Python formatting check failed. See formatting.diff artifact for details."
          echo "To fix the error(s) run the command below from the root of the repo and commit the changes:"
          echo "./.github/scripts/fix-python-formatting.sh"
          exit 1

      - name: Fail if only flake8 failed
        if: steps.black_check.outputs.black_failed != 'true' && env.FLAKE8_ISSUE_PRESENT == 'true'
        run: |
          echo "❌  Issues detected in Python files. Please fix them before merging."
          echo "Download the full report from here: $RUN_URL"
          exit 1