env: add additional target for building env images

Revise Makefile in linux-x86-std-kube and linux-x86-nacl:

- Support a target named `dev` that allows specifying a non-default
  Docker repository name.

- Replace hard-coded image names with the directory name that Makefile
  resides in. This uses the existing convention of naming directories
  according to image name.

- When Dockerfile inherits from a custom image (i.e., linux-x86-nacl
  inherits FROM linux-x86-std-kube), use sed to dynamically set the
  repository prefix in the Dockerfile.

Change-Id: I372c834175a38bb34d80a18f2f0e23c5a1d007af
Reviewed-on: https://go-review.googlesource.com/19021
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

env/linux-x86-nacl/Dockerfile

@@ -7,7 +7,7 @@
 # We need more modern libc than Debian stable as used in base, so we're
 # using Debian sid instead.
 
-FROM gcr.io/symbolic-datum-552/linux-x86-std:latest
+FROM {{REPO}}/linux-x86-std:latest
 MAINTAINER golang-dev <golang-dev@googlegroups.com>
 
 ENV DEBIAN_FRONTEND noninteractive

env/linux-x86-nacl/Makefile

@@ -1,13 +1,30 @@
 # Copyright 2015 The Go Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
+IMAGE_NAME=$(shell basename $(CURDIR))
+STAGING_REPO=gcr.io/go-dashboard-dev
+PROD_REPO=gcr.io/symbolic-datum-552
+
 usage:
-	echo "Use staging or prod targets" ; exit 1
+	echo "Use staging, prod, or dev targets. For dev, specify your Docker repository with the REPO=foo argument." ; exit 1
 
 staging: Dockerfile
-	docker build -t gcr.io/go-dashboard-dev/linux-x86-nacl:latest .
-	gcloud docker push gcr.io/go-dashboard-dev/linux-x86-nacl:latest
+	sed 's|{{REPO}}|'"$(STAGING_REPO)"'|g' Dockerfile > Dockerfile.make
+	docker build -t $(STAGING_REPO)/$(IMAGE_NAME):latest -f Dockerfile.make .
+	gcloud docker push $(STAGING_REPO)/$(IMAGE_NAME):latest
+	rm Dockerfile.make
 
 prod: Dockerfile
-	docker build -t gcr.io/symbolic-datum-552/linux-x86-nacl:latest .
-	gcloud docker push gcr.io/symbolic-datum-552/linux-x86-nacl:latest
+	sed 's|{{REPO}}|'"$(PROD_REPO)"'|g' Dockerfile > Dockerfile.make
+	docker build -t $(PROD_REPO)/$(IMAGE_NAME):latest -f Dockerfile.make .
+	gcloud docker push $(PROD_REPO)/$(IMAGE_NAME):latest
+	rm Dockerfile.make
+
+# You must provide a REPO=your-repo-name arg when you make
+# this targarget. REPO is the name of the Docker repository
+# that will be prefixed to the name of the image being built.
+dev: Dockerfile
+	sed 's|{{REPO}}|'"$(REPO)"'|g' Dockerfile > Dockerfile.make
+	docker build -t $(REPO)/$(IMAGE_NAME):latest -f Dockerfile.make .
+	gcloud docker push $(REPO)/$(IMAGE_NAME):latest
+	rm Dockerfile.make

env/linux-x86-nacl/README

@@ -1,3 +1,16 @@
+# Building Docker image
+If you have access to the Go build staging project (`go-dashboard-dev`) or
+production project (`symbolic-datum-552`), use the `make staging` or `make
+prod` targets to build a Docker image and push it to the correct Docker
+repository.
+
+To build the image for your own dev environment, first build the
+`linux-x86-std-kube` image with `make dev REPO=your/docker/repo/prefix`, then
+build this image using the same repo prefix, i.e.,
+`make dev REPO=your/docker/repo/prefix`.
+
+
+# Running locally
 $ export BUILD=nacl-amd64p32-temp
 $ export BUILDREV=59b1bb4bf045 
 $ docker run \

env/linux-x86-std-kube/Makefile

@@ -1,13 +1,24 @@
 # Copyright 2015 The Go Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style
 # license that can be found in the LICENSE file.
+IMAGE_NAME=$(shell basename $(CURDIR))
+STAGING_REPO=gcr.io/go-dashboard-dev
+PROD_REPO=gcr.io/symbolic-datum-552
+
 usage:
-	echo "Use staging or prod targets" ; exit 1
+	echo "Use staging, prod, or dev targets. For dev, specify your Docker repository with the REPO=foo argument." ; exit 1
 
 staging: Dockerfile
-	docker build -t gcr.io/go-dashboard-dev/linux-x86-std:latest .
-	gcloud docker push gcr.io/go-dashboard-dev/linux-x86-std:latest
+	docker build -t $(STAGING_REPO)/$(IMAGE_NAME):latest .
+	gcloud docker push $(STAGING_REPO)/$(IMAGE_NAME):latest
 
 prod: Dockerfile
-	docker build -t gcr.io/symbolic-datum-552/linux-x86-std:latest .
-	gcloud docker push gcr.io/symbolic-datum-552/linux-x86-std:latest
+	docker build -t $(PROD_REPO)/$(IMAGE_NAME):latest .
+	gcloud docker push $(PROD_REPO)/$(IMAGE_NAME):latest
+
+# You must provide a REPO=your-repo-name arg when you make
+# this targarget. REPO is the name of the Docker repository
+# that will be prefixed to the name of the image being built.
+dev: Dockerfile
+	docker build -t $(REPO)/$(IMAGE_NAME):latest .
+	gcloud docker push $(REPO)/$(IMAGE_NAME):latest