Fix build

- Update labels to match those from https://github.com/opencontainers/image-spec/blob/master/annotations.md#pre-defined-annotation-keys
- Add missing build args.
- Remove unneeded python (which was failing to install, BTW) from the image.
- Remove `hooks` folder, which was used to build the image automatically in the Docker Hub. It's done in GitHub Actions now.

Author: Jairo Llopis

.github/workflows/test.yaml

@@ -29,6 +29,8 @@ jobs:
     env:
       DOCKER_REPO: tecnativa/docker-socket-proxy
     steps:
+      - name: Get date
+        run: echo "BUILD_DATE=$(date --rfc-3339 ns)" >> $GITHUB_ENV
       # Prepare Docker environment and build
       - uses: actions/checkout@v2
       - uses: docker/setup-qemu-action@v1
@@ -37,6 +39,9 @@ jobs:
       - name: Build image(s)
         uses: docker/build-push-action@v2
         with:
+          build-args: |
+            BUILD_DATE=${{ env.BUILD_DATE }}
+            VCS_REF=${{ github.sha }}
           context: .
           file: ./Dockerfile
           # HACK: Build single platform image for testing. See https://github.com/docker/buildx/issues/59
@@ -93,6 +98,9 @@ jobs:
           'refs/heads/master'
         uses: docker/build-push-action@v2
         with:
+          build-args: |
+            BUILD_DATE=${{ env.BUILD_DATE }}
+            VCS_REF=${{ github.sha }}
           context: .
           file: ./Dockerfile
           platforms: linux/386,linux/amd64,linux/arm/v6,linux/arm/v7,linux/arm/v8,linux/arm64,linux/ppc64le,linux/s390x

Dockerfile

@@ -1,5 +1,4 @@
-ARG REPO=library
-FROM ${REPO}/haproxy:1.9-alpine
+FROM haproxy:1.9-alpine
 
 EXPOSE 2375
 ENV ALLOW_RESTARTS=0 \
@@ -29,17 +28,11 @@ ENV ALLOW_RESTARTS=0 \
     VOLUMES=0
 COPY haproxy.cfg /usr/local/etc/haproxy/haproxy.cfg
 
-# Install python/pip
-ENV PYTHONUNBUFFERED=1
-RUN apk add --update --no-cache python3 && ln -sf $(which python3) /usr/local/bin/python
-RUN python -m ensurepip && python -m pip install --no-cache --upgrade pip setuptools
-
 # Metadata
 ARG VCS_REF
 ARG BUILD_DATE
-LABEL org.label-schema.schema-version="1.0" \
-      org.label-schema.vendor=Tecnativa \
-      org.label-schema.license=Apache-2.0 \
-      org.label-schema.build-date="$BUILD_DATE" \
-      org.label-schema.vcs-ref="$VCS_REF" \
-      org.label-schema.vcs-url="https://github.com/Tecnativa/docker-socket-proxy"
+LABEL org.opencontainers.image.vendor=Tecnativa \
+      org.opencontainers.image.licenses=Apache-2.0 \
+      org.opencontainers.image.created="$BUILD_DATE" \
+      org.opencontainers.image.revision="$VCS_REF" \
+      org.opencontainers.image.source="https://github.com/Tecnativa/docker-socket-proxy"