fix(nightly) Wait 30 min before building nightly images (#3294)

Signed-off-by: Robert Steiner <robert@flower.ai>

.github/workflows/release-nightly.yml

@@ -3,6 +3,7 @@ name: Release nightly
 on:
   schedule:
     - cron: "0 23 * * *"
+    - cron: "30 23 * * *"
 
 env:
   FLWR_TELEMETRY_ENABLED: 0
@@ -15,36 +16,33 @@ jobs:
     outputs:
       name: ${{ steps.release.outputs.name }}
       version: ${{ steps.release.outputs.version }}
+      skip: ${{ steps.release.outputs.skip }}
     steps:
       - uses: actions/checkout@v4
       - name: Bootstrap
         uses: ./.github/actions/bootstrap
       - name: Release nightly
-        id: release
+        if: github.event.schedule == '0 23 * * *'
         env:
           PYPI_TOKEN: ${{ secrets.PYPI_TOKEN }}
+        run: ./dev/publish-nightly.sh
+      - name: Read nightly version and name
+        if: github.event.schedule == '30 23 * * *'
+        id: release
         run: |
-          ./dev/publish-nightly.sh
+          RESULT=$(./dev/publish-nightly.sh --skip-publish)
+          if [ "$RESULT" == "There were no commits in the last 24 hours." ]; then
+            echo "skip=true" >> $GITHUB_OUTPUT
+          fi
+
           echo "name=$(poetry version | awk {'print $1'})" >> $GITHUB_OUTPUT
           echo "version=$(poetry version -s)" >> $GITHUB_OUTPUT
 
-  wait-on-pypi:
-    runs-on: ubuntu-22.04
-    timeout-minutes: 5
-    name: Wait on PyPI
-    needs: release-nightly
-    steps:
-      - uses: actions/checkout@v4
-      - name: Bootstrap
-        uses: ./.github/actions/bootstrap
-      - name: Wait until flwr package is avaiale on PyPI
-        run: until pip install ${{ needs.release-nightly.outputs.name }}==${{ needs.release-nightly.outputs.version }} --dry-run; do echo "Try again"; sleep 10; done
-
   build-docker-images:
     name: Build nightly images
-    if: github.repository == 'adap/flower'
+    if: github.repository == 'adap/flower' && needs.release-nightly.outputs.skip != 'true' && github.event.schedule == '30 23 * * *'
     uses: ./.github/workflows/_docker-build.yml
-    needs: [release-nightly, wait-on-pypi]
+    needs: release-nightly
     strategy:
       fail-fast: false
       matrix:

dev/publish-nightly.sh

@@ -24,12 +24,16 @@ cd "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/../
 # The version name in the pyproject.toml will be appended with "-dev" and the current date.
 # The result will be a release on PyPi of the package "flwr-nightly" of version e.g.
 # "0.1.1.dev20200716" as seen at https://pypi.org/project/flwr-nightly/
+# If the script is called with the flag `--skip-publish`, the name and version are changed
+# in the pyproject.toml but the package won't be published.
 
 if [[ $(git log --since="24 hours ago" --pretty=oneline) ]]; then
     sed -i -E "s/^name = \"(.+)\"/name = \"\1-nightly\"/" pyproject.toml
     sed -i -E "s/^version = \"(.+)\"/version = \"\1.dev$(date '+%Y%m%d')\"/" pyproject.toml
-    python -m poetry build
-    python -m poetry publish -u __token__ -p $PYPI_TOKEN
+    if [ "$1" != "--skip-publish" ]; then
+        python -m poetry build
+        python -m poetry publish -u __token__ -p $PYPI_TOKEN
+    fi
 else
     echo "There were no commits in the last 24 hours."
 fi