ci(helm): update helm chart version fix

When pushing tags (annotated?), github's event.base_ref may not be set.
When this happens, we can figure out the released branch ourselves, by
inspecting all branches containing the tag, and ensuring it's the tip
and it's the current HEAD.

Signed-off-by: Tiago Castro <[email protected]>

.github/workflows/release-chart.yml

@@ -55,7 +55,13 @@ jobs:
         run: |
           tag="${{ github.ref_name }}"
           BASE_REF="${{ github.event.base_ref }}"
-          BRANCH="${BASE_REF#refs/heads/}"
+          if [ -n "$BASE_REF" ]; then
+            BRANCH="${BASE_REF#refs/heads/}"
+          else
+            BRANCH="$(nix-shell --pure --run "./scripts/helm/find-released-branch.sh "$tag"" ./scripts/helm/shell.nix)"
+          fi
+          echo "BASE_BRANCH=$BRANCH" >> $GITHUB_ENV
+
           nix-shell --pure --run "./scripts/helm/publish-chart-yaml.sh --released "$tag" --released-branch "$BRANCH"" ./scripts/helm/shell.nix
           nix-shell --pure --run "SKIP_GIT=1 ./scripts/helm/generate-readme.sh" ./scripts/helm/shell.nix
       - name: Create Pull Request
@@ -73,7 +79,7 @@ jobs:
           signoff: true
           delete-branch: true
           branch-suffix: "random"
-          base: ${{ github.event.base_ref }}
+          base: ${{ env.BASE_BRANCH }}
           token: ${{ secrets.ORG_CI_GITHUB }}
       - name: Approve Pull Request by CI Bot
         if: ${{ steps.cpr.outputs.pull-request-number }}

scripts/helm/find-released-branch.sh

@@ -0,0 +1,55 @@
+#!/usr/bin/env bash
+
+SCRIPTDIR="$(dirname "$(realpath "${BASH_SOURCE[0]:-"$0"}")")"
+ROOTDIR="$SCRIPTDIR/../.."
+
+source "$ROOTDIR/scripts/utils/log.sh"
+
+set -euo pipefail
+
+# Check if the given branch matches the tag
+# Example:
+# release/2.7 matches tag v2.7.2, v2.7.2-rc.4, etc..
+# release/2.7 does not match tag v2.6.0, etc...
+tag_matches_branch() {
+  local tag="${1#v}"
+  local release_branch="$2"
+
+  branch_version="${release_branch#release/}"
+  if ! [[ "$branch_version" =~ ^[0-9]+.[0-9]+$ ]]; then
+    return 1
+  fi
+
+  if ! [[ "$tag" = "$branch_version"* ]]; then
+    return 1
+  fi
+}
+
+# For the given tag, find the branch which is compatible
+# See tag_matches_branch for more information.
+find_released_branch() {
+  local tag="$1"
+  local branches=$(git branch -r --contains "$TAG" --points-at "$TAG" --format "%(refname:short)" 2>/dev/null)
+  local branch=""
+
+  for release_branch in $branches; do
+    release_branch=${release_branch#origin/}
+    if tag_matches_branch "$TAG" "$release_branch"; then
+      if [ -n "$branch" ]; then
+        log_fatal "Multiple branches matched!"
+      fi
+      branch="$release_branch"
+    fi
+  done
+
+  echo "$branch"
+}
+
+TAG="$1"
+BRANCH="$(find_released_branch "$TAG")"
+
+if [ -z "$BRANCH" ]; then
+  log_fatal "Failed to find matching released branch for tag '$TAG'"
+fi
+
+echo "$BRANCH"