Update workflows to use docker metadata

Author: chrissearle

.github/workflows/backend.yaml

@@ -49,17 +49,27 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ github.token }}
 
+      - name: Docker metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ghcr.io/javabin/cupcake
+          tags: |
+            type=ref,event=branch
+            type=ref,event=tag
+            type=sha,format=short
+            type=raw,value=latest,enable={{is_default_branch}}
+
       - name: Build and push
         uses: docker/build-push-action@v6
         with:
-          context: ./backend
+          context: .
           platforms: linux/amd64,linux/arm64
           push: true
-          tags: |
-            ghcr.io/javabin/cupcake:${{ github.sha }}
-            ghcr.io/javabin/cupcake:latest
-          labels: |
-            org.opencontainers.image.source=https://github.com/${{ github.repository }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
 
       - name: Create staging
         if: github.ref == 'refs/heads/main'

.github/workflows/frontend.yaml

@@ -36,17 +36,27 @@ jobs:
           username: ${{ github.actor }}
           password: ${{ github.token }}
 
+      - name: Docker metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: ghcr.io/javabin/frosting
+          tags: |
+            type=ref,event=branch
+            type=ref,event=tag
+            type=sha,format=short
+            type=raw,value=latest,enable={{is_default_branch}}
+
       - name: Build and push
         uses: docker/build-push-action@v6
         with:
-          context: ./frontend
+          context: .
           platforms: linux/amd64,linux/arm64
           push: true
-          tags: |
-            ghcr.io/javabin/frosting:${{ github.sha }}
-            ghcr.io/javabin/frosting:latest
-          labels: |
-            org.opencontainers.image.source=https://github.com/${{ github.repository }}
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max
 
       - name: Create staging
         if: github.ref == 'refs/heads/main'