Add create release & publish to pypi actions (#4)

Author: stefan-brus-frequenz

.github/workflows/ci.yaml

@@ -1,6 +1,6 @@
 name: frequenz-api-dispatch
 
-on: [pull_request, push, release]
+on: [pull_request, push]
 
 # Ensure old CI runs still being in progress are cancelled.
 concurrency:
@@ -58,3 +58,97 @@ jobs:
           python -m pip install .[dev-noxfile]
       - name: Run nox
         run: nox
+
+  build-dist:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Fetch sources
+        uses: actions/checkout@v3
+        with:
+          submodules: true
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.11"
+
+      - name: Install build dependencies
+        run: |
+          python -m pip install -U pip
+          python -m pip install -U build
+
+      - name: Build the source and binary distribution
+        run: python -m build
+
+      - name: Upload dist files
+        uses: actions/upload-artifact@v3
+        with:
+          name: frequenz-api-dispatch-dist
+          path: dist/
+          if-no-files-found: error
+
+  create-github-release:
+    needs: ["protolint", "gen-docs", "tests", "build-dist"]
+    # Create a release only on tags creation
+    if: github.event_name == 'push' && startsWith(github.ref, 'refs/tags')
+    permissions:
+      # We need write permissions on contents to create GitHub releases and on
+      # discussions to create the release announcement in the discussion forums
+      contents: write
+      discussions: write
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Download dist files
+        uses: actions/download-artifact@v3
+        with:
+          name: frequenz-api-dispatch-dist
+          path: dist
+
+      - name: Download RELEASE_NOTES.md
+        run: |
+          set -ux
+          gh api \
+              -X GET \
+              -f ref=$REF \
+              -H "Accept: application/vnd.github.raw" \
+              "/repos/$REPOSITORY/contents/RELEASE_NOTES.md" \
+            > RELEASE_NOTES.md
+        env:
+          REF: ${{ github.ref }}
+          REPOSITORY: ${{ github.repository }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Create GitHub release
+        run: |
+          set -ux
+          extra_opts=
+          if echo "$REF_NAME" | grep -- -; then extra_opts=" --prerelease"; fi
+          gh release create \
+            -R "$REPOSITORY" \
+            --discussion-category announcements \
+            --notes-file RELEASE_NOTES.md \
+            --generate-notes \
+            $extra_opts \
+            $REF_NAME \
+            dist/*
+        env:
+          REF_NAME: ${{ github.ref_name }}
+          REPOSITORY: ${{ github.repository }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+  publish-to-pypi:
+    needs: ["create-github-release"]
+    runs-on: ubuntu-20.04
+    permissions:
+      # For trusted publishing. See:
+      # https://blog.pypi.org/posts/2023-04-20-introducing-trusted-publishers/
+      id-token: write
+    steps:
+      - name: Download dist files
+        uses: actions/download-artifact@v3
+        with:
+          name: frequenz-api-dispatch-dist
+          path: dist
+
+      - name: Publish the Python distribution to PyPI
+        uses: pypa/gh-action-pypi-publish@release/v1