Build image on pull request (#522)

.github/workflows/docker.yaml

@@ -1,6 +1,15 @@
 name: docker
 
 on:
+  pull_request:
+    branches:
+      - master
+    paths:
+      - .github/workflows/docker.yaml
+      - pkg/**
+      - go.*
+      - Dockerfile
+      - Makefile
   push:
     branches:
       - master
@@ -9,6 +18,7 @@ on:
       - pkg/**
       - go.*
       - Dockerfile
+      - Makefile
     tags:
       - v*
 
@@ -19,9 +29,17 @@ jobs:
       - uses: actions/checkout@v2
       - uses: docker/setup-qemu-action@v1
       - uses: docker/setup-buildx-action@v1
+      - uses: actions/cache@v2
+        with:
+          path: /tmp/buildx
+          key: buildx-${{ runner.os }}-${{ github.sha }}
+          restore-keys: |
+            buildx-${{ runner.os }}-
       - uses: docker/login-action@v1
         with:
           registry: ghcr.io
           username: ${{ github.repository_owner }}
-          password: ${{ secrets.CR_PAT }}
-      - run: make docker-build-push
+          password: ${{ secrets.GITHUB_TOKEN }}
+      - uses: int128/buildx-push-action@v1
+        with:
+          extra-args: --platform=linux/amd64,linux/arm64

Dockerfile

@@ -6,8 +6,7 @@ RUN go mod download
 COPY Makefile .
 COPY main.go .
 COPY pkg pkg
-ARG VERSION
-RUN make VERSION=$VERSION
+RUN make
 
 FROM gcr.io/distroless/base-debian10
 COPY --from=builder /builder/kubelogin /

Makefile

@@ -36,18 +36,6 @@ endif
 dist-release: dist
 	gh release upload $(VERSION) $(TARGET_ARCHIVE) $(TARGET_DIGEST) --clobber
 
-DOCKER_REPOSITORY := ghcr.io/int128/kubelogin
-
-.PHONY: docker-build-push
-docker-build-push: Dockerfile
-	docker buildx build . \
-		--build-arg=VERSION=$(VERSION) \
-		--tag=$(DOCKER_REPOSITORY):$(VERSION) \
-		--cache-from=type=registry,ref=$(DOCKER_REPOSITORY):latest \
-		--cache-to=type=inline \
-		--platform=linux/amd64,linux/arm64 \
-		--push
-
 .PHONY: clean
 clean:
 	-rm $(TARGET)