🚧 github: Use a matrix build to DRY

.github/workflows/build.yml

@@ -10,6 +10,9 @@ on:
 
 jobs:
   docker:
+    strategy:
+      matrix:
+        subimage: ["core", "dinglehopper"]  # core images need to come first!
     runs-on: ubuntu-latest
     steps:
       -
@@ -23,7 +26,6 @@ jobs:
         uses: docker/setup-buildx-action@v2
 
       # TODO data
-      # TODO matrix for all Dockerfiles
       -
         name: Login to Docker Hub
         uses: docker/login-action@v2
@@ -31,22 +33,12 @@ jobs:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
       -
-        name: Build core
+        name: Build ${{ matrix.subimage }}
         uses: docker/build-push-action@v4
         with:
           context: .
-          file: Dockerfile-core
+          file: Dockerfile-${{ matrix.subimage }}
           build-args:
             DRONE_COMMIT=${{ github.sha }}
           push: true
-          tags: quratorspk/ocrd-galley-core:${{ github.sha }}
-      -
-        name: Build dinglehopper
-        uses: docker/build-push-action@v4
-        with:
-          context: .
-          file: Dockerfile-dinglehopper
-          build-args:
-            DRONE_COMMIT=${{ github.sha }}
-          push: true
-          tags: quratorspk/ocrd-galley-dinglehopper:${{ github.sha }}
+          tags: quratorspk/ocrd-galley-${{ matrix.subimage }}:${{ github.sha }}