add md5 checksum of dockerfiles to image labels (#967)

Author: dklimpel

.github/workflows/docker-integration-tests.yaml

@@ -61,12 +61,19 @@ jobs:
           username: ${{ github.repository_owner }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
+      - name: MD5 of Dockerfile
+        id: md5_result
+        run: |
+          echo "md5=$(md5sum "${{ matrix.dockerfile }}" | awk '{ print $1 }')" >> $GITHUB_OUTPUT
+
       - name: Extract metadata (tags, labels) for Docker
         id: meta
         uses: docker/metadata-action@v5
         with:
           images: |
             ghcr.io/${{ github.repository_owner }}/${{ matrix.image }}
+          labels: |
+            rocks.goss.dockerfile-md5=${{ steps.md5_result.outputs.md5 }}
 
       - name: Build and push tag
         uses: docker/build-push-action@v5

development/build_images.sh

@@ -12,6 +12,7 @@ LABEL_REVISION=$(git rev-parse HEAD)
 for docker_file in $INTEGRATION_TEST_DIR/Dockerfile_*; do
     [[ $docker_file == *.md5 ]] && continue
     os=$(cut -d '_' -f2 <<<"$docker_file")
+    md5=$(md5sum "$docker_file" | awk '{ print $1 }')
     docker build \
         --label "org.opencontainers.image.created=$LABEL_DATE" \
         --label "org.opencontainers.image.description=Quick and Easy server testing/validation" \
@@ -21,5 +22,6 @@ for docker_file in $INTEGRATION_TEST_DIR/Dockerfile_*; do
         --label "org.opencontainers.image.title=goss" \
         --label "org.opencontainers.image.url=$LABEL_URL" \
         --label "org.opencontainers.image.version=manual" \
+        --label "rocks.goss.dockerfile-md5"=$md5 \
         -t "aelsabbahy/goss_${os}:latest" - < "$docker_file"
 done