Push all images to GitHub Container Registry in addition to Docker Hub (

#62)

We are transitioning from DockerHub to GHCR. While that transition is
underway, we are pushing images to both registries.

.github/workflows/release.yml

@@ -32,11 +32,18 @@ jobs:
       - pre-artefact-creation
     steps:
       - uses: actions/checkout@v3
-      - name: Docker login
+      - name: Login to DockerHub
         run: docker login -u "$DOCKER_USERNAME" -p "$DOCKER_PASSWORD"
         env:
           DOCKER_PASSWORD: ${{ secrets.DOCKER_PASSWORD }}
           DOCKER_USERNAME: ${{ secrets.DOCKER_USERNAME }}
+      - name: Login to GitHub Container Registry
+        # v2.2.0
+        uses: docker/login-action@465a07811f14bebb1938fbed4728c6a1ff8901fc
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
       - name: Build and push
         run: make push
 

Makefile

@@ -13,16 +13,20 @@ all: build
 build: action.yml Dockerfile entrypoint scripts/*
 	docker build --pull -t "${IMAGE}:${IMAGE_TAG}" .
 	docker build --pull -t "${IMAGE}:latest" .
+	docker build --pull -t "ghcr.io/${IMAGE}:${IMAGE_TAG}" .
+	docker build --pull -t "ghcr.io/${IMAGE}:latest" .
 	touch $@
 
 push: build
 	docker push "${IMAGE}:${IMAGE_TAG}"
 	docker push "${IMAGE}:latest"
+	docker push "ghcr.io/${IMAGE}:${IMAGE_TAG}"
+	docker push "ghcr.io/${IMAGE}:latest"
 
 pylint: build $(PYTHON_COMMANDS)
 	$(foreach file, $(notdir $(PYTHON_COMMANDS)), \
 		echo "Linting $(file)"; \
-		docker run --entrypoint pylint --rm "${IMAGE}:latest" /commands/$(file); \
+		docker run --entrypoint pylint --rm "ghcr.io/${IMAGE}:latest" /commands/$(file); \
 	)
 
 .PHONY: push