Added gcr.io push to Makefile

Makefile

@@ -14,8 +14,21 @@
 
 .PHONY: all csi-attacher clean test
 
-IMAGE_NAME=docker.io/k8scsi/csi-attacher
-IMAGE_VERSION=latest
+GCR_IMAGE_PATH=gcr.io/google-containers/sig-storage/csi/external-attacher
+DOCKER_IMAGE_PATH=docker.io/k8scsi/csi-attacher
+
+IMAGE_VERSION :=
+TAG := $(shell git describe --abbrev=0 --tags HEAD 2>/dev/null)
+COMMIT := $(shell git rev-parse HEAD)
+ifeq ($(TAG),)
+    IMAGE_VERSION := latest
+else
+    ifeq ($(COMMIT), $(shell git rev-list -n1 $(TAG)))
+        IMAGE_VERSION := $(TAG)
+    else
+        IMAGE_VERSION := $(TAG)-$(COMMIT)
+    endif
+endif
 
 ifdef V
 TESTARGS = -v -args -alsologtostderr -v 5
@@ -34,10 +47,15 @@ clean:
 
 container: csi-attacher
 	cp csi-attacher deploy/docker
-	docker build -t $(IMAGE_NAME):$(IMAGE_VERSION) deploy/docker
+	docker build -t $(DOCKER_IMAGE_PATH):$(IMAGE_VERSION) deploy/docker
 
 push: container
-	docker push $(IMAGE_NAME):$(IMAGE_VERSION)
+	docker push $(DOCKER_IMAGE_PATH):$(IMAGE_VERSION)
+
+gcr-push: csi-attacher
+	cp bin/csi-attacher deploy/docker
+	docker build -t $(GCR_IMAGE_PATH):$(IMAGE_VERSION) deploy/docker
+	gcloud docker -- push $(GCR_IMAGE_PATH):$(IMAGE_VERSION)
 
 test:
 	go test `go list ./... | grep -v 'vendor'` $(TESTARGS)