Move check to separate job

.gitea/workflows/timelimit-server-ui.yml

@@ -6,14 +6,12 @@ on:
   workflow_dispatch:
 
 jobs:
-  build:
+  check:
     runs-on: ubuntu-latest
-
+    outputs:
+      exists: ${{ steps.exists.outputs.exists }}
+      sha: ${{ steps.sha.outputs.sha }}
     steps:
-      # Checkout THIS repository (Dockerfile lives here)
-      - name: Checkout current repository
-        uses: actions/checkout@v4
-
       # Get latest timelimit-server-ui commit SHA
       - name: Get timelimit-server-ui commit SHA
         id: sha
@@ -21,13 +19,6 @@ jobs:
           SHA=$(git ls-remote https://gitea.furb.it/${{ vars.FRONTEND_PATH }}.git refs/heads/${{ vars.FRONTEND_BRANCH }} | cut -f1)
           echo "sha=$SHA" >> $GITEA_OUTPUT
 
-      # Login to registry (needed to inspect latest image)
-      - name: Docker login
-        run: |
-          echo "${{ secrets.ACCESS_TOKEN }}" | docker login gitea.furb.it \
-            -u "${{ secrets.USERNAME }}" \
-            --password-stdin
-
       # Try to read timelimit-server-ui SHA from latest image label
       - name: Check if image with timelimit-server-ui SHA exists
         id: exists
@@ -45,20 +36,21 @@ jobs:
             echo "exists=false" >> $GITEA_OUTPUT
           fi
 
-      # Exit early if unchanged
-      - name: Skip build if image already exists
-        run: |
-          if [ "${{ steps.exists.outputs.exists }}" = "true" ]; then
-            echo "Image for this timelimit-server-ui commit already exists. Skipping build."
-            exit 0
-          fi
+  build:
+    runs-on: ubuntu-latest
+    needs: check
+    if: needs.check.outputs.exists == 'false'
+    steps:
+      # Checkout THIS repository (Dockerfile lives here)
+      - name: Checkout current repository
+        uses: actions/checkout@v4
 
       # Checkout timelimit-server-ui repository for build
       - name: Checkout timelimit-server-ui repository
         uses: actions/checkout@v4
         with:
           repository: ${{ vars.FRONTEND_PATH }}.git
-          ref: ${{ steps.sha.outputs.sha }}
+          ref: ${{ needs.check.outputs.sha }}
           path: timelimit-server-ui
           token: ${{ secrets.ACCESS_TOKEN }}
 
@@ -84,18 +76,25 @@ jobs:
           rm -rf dist
           cp -r timelimit-server-ui/dist ./dist
 
+      # Login to registry (needed to inspect latest image)
+      - name: Docker login
+        run: |
+          echo "${{ secrets.ACCESS_TOKEN }}" | docker login gitea.furb.it \
+            -u "${{ secrets.USERNAME }}" \
+            --password-stdin
+
       # Build image with commit-SHA tag and label
       - name: Build Docker image
         run: |
           docker build \
             -f Dockerfile-ui \
-            --label timelimit-server-ui.sha=${{ steps.sha.outputs.sha }} \
-            -t gitea.furb.it/${{ vars.FRONTEND_IMAGE }}:${{ steps.sha.outputs.sha }} \
+            --label timelimit-server-ui.sha=${{ needs.check.outputs.sha }} \
+            -t gitea.furb.it/${{ vars.FRONTEND_IMAGE }}:${{ needs.check.outputs.sha }} \
             -t gitea.furb.it/${{ vars.FRONTEND_IMAGE }}:latest \
             .
 
       # Push images
       - name: Push Docker images
         run: |
-          docker push gitea.furb.it/${{ vars.FRONTEND_IMAGE }}:${{ steps.sha.outputs.sha }}
+          docker push gitea.furb.it/${{ vars.FRONTEND_IMAGE }}:${{ needs.check.outputs.sha }}
           docker push gitea.furb.it/${{ vars.FRONTEND_IMAGE }}:latest