Update workflow to rebuild daily

.gitea/workflows/build.yml

@@ -5,14 +5,22 @@ on:
     branches:
       - main
       - develop
+  schedule:
+    - cron: '0 4 * * *'  # Daily at 4:00 UTC
   workflow_dispatch:
 
 jobs:
   build:
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        # On schedule/dispatch, build both branches; otherwise only the pushed branch
+        branch: ${{ github.event_name == 'schedule' && fromJson('["main", "develop"]') || fromJson(format('["{0}"]', github.ref_name)) }}
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          ref: ${{ matrix.branch }}
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
@@ -23,25 +31,39 @@ jobs:
           # Date ISO 8601
           echo "build_date=$(date -u +%Y-%m-%dT%H:%M:%S%z)" >> "$GITHUB_OUTPUT"
 
-          # Short SHA
+          # Short SHA of docker-prowlarr repo
-          echo "sha_short=$(echo ${GITHUB_SHA} | cut -c1-7)" >> "$GITHUB_OUTPUT"
+          echo "sha_short=$(git rev-parse --short HEAD)" >> "$GITHUB_OUTPUT"
 
-          # Prowlarr version from upstream API
+          # Corresponding upstream Prowlarr branch
           PROWLARR_BRANCH="develop"
-          if [ "${GITHUB_REF_NAME}" = "main" ]; then
+          if [ "${{ matrix.branch }}" = "main" ]; then
             PROWLARR_BRANCH="master"
           fi
           echo "prowlarr_branch=${PROWLARR_BRANCH}" >> "$GITHUB_OUTPUT"
 
+          # Latest commit SHA on the upstream Prowlarr repo
+          UPSTREAM_SHA=$(git ls-remote https://github.com/Prowlarr/Prowlarr.git "refs/heads/${PROWLARR_BRANCH}" | awk '{print $1}')
+          UPSTREAM_SHA_SHORT=$(echo "${UPSTREAM_SHA}" | cut -c1-7)
+          echo "upstream_sha=${UPSTREAM_SHA}" >> "$GITHUB_OUTPUT"
+          echo "upstream_sha_short=${UPSTREAM_SHA_SHORT}" >> "$GITHUB_OUTPUT"
+          echo "Prowlarr upstream ${PROWLARR_BRANCH} is at ${UPSTREAM_SHA_SHORT}"
+
+          # Prowlarr version from upstream API
           PROWLARR_VERSION=$(curl -sL "https://prowlarr.servarr.com/v1/update/${PROWLARR_BRANCH}/changes?runtime=netcore&os=linuxmusl" | jq -r '.[0].version')
           echo "prowlarr_version=${PROWLARR_VERSION}" >> "$GITHUB_OUTPUT"
 
           # Image name
           REGISTRY="${{ vars.OCI_REGISTRY }}"
-          # Remove trailing slash if present
           REGISTRY="${REGISTRY%/}"
           echo "image_name=${REGISTRY}/prowlarr" >> "$GITHUB_OUTPUT"
 
+          # Channel tag: latest for main, develop for develop
+          if [ "${{ matrix.branch }}" = "main" ]; then
+            echo "channel_tag=latest" >> "$GITHUB_OUTPUT"
+          else
+            echo "channel_tag=develop" >> "$GITHUB_OUTPUT"
+          fi
+
       - name: Login to OCI Registry
         uses: docker/login-action@v3
         with:
@@ -49,7 +71,23 @@ jobs:
           username: ${{ vars.OCI_USERNAME }}
           password: ${{ vars.OCI_PASSWORD }}
 
+      - name: Check if upstream version already built
+        id: check
+        if: github.event_name == 'schedule'
+        run: |
+          # Check if an image tagged with the upstream SHA already exists
+          IMAGE="${{ steps.vars.outputs.image_name }}:${{ steps.vars.outputs.prowlarr_branch }}-${{ steps.vars.outputs.upstream_sha_short }}"
+          echo "Checking if ${IMAGE} already exists..."
+          if docker manifest inspect "${IMAGE}" > /dev/null 2>&1; then
+            echo "Image ${IMAGE} already exists — no upstream changes, skipping build."
+            echo "skip=true" >> "$GITHUB_OUTPUT"
+          else
+            echo "Image ${IMAGE} not found — upstream has changed, proceeding with build."
+            echo "skip=false" >> "$GITHUB_OUTPUT"
+          fi
+
       - name: Build and push
+        if: steps.check.outputs.skip != 'true'
         uses: docker/build-push-action@v6
         with:
           context: .
@@ -60,8 +98,9 @@ jobs:
             VERSION=${{ steps.vars.outputs.prowlarr_version }}-custom
             PROWLARR_BRANCH=${{ steps.vars.outputs.prowlarr_branch }}
           tags: |
-            ${{ steps.vars.outputs.image_name }}:latest
+            ${{ steps.vars.outputs.image_name }}:${{ steps.vars.outputs.channel_tag }}
             ${{ steps.vars.outputs.image_name }}:${{ steps.vars.outputs.sha_short }}
             ${{ steps.vars.outputs.image_name }}:${{ steps.vars.outputs.prowlarr_version }}-custom
+            ${{ steps.vars.outputs.image_name }}:${{ steps.vars.outputs.prowlarr_branch }}-${{ steps.vars.outputs.upstream_sha_short }}
           cache-from: type=gha
           cache-to: type=gha,mode=max