Add base image (busybox) for other arch's

.gitignore

@@ -2,3 +2,4 @@
 /.go
 /.push-*
 /.container-*
+/.dockerfile-*

Dockerfile.in

@@ -12,13 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM alpine:3.4
+FROM ARG_FROM
 
 MAINTAINER Tim Hockin <thockin@google.com>
 
-ARG ARCH
-
-ADD bin/${ARCH}/myapp /myapp
+ADD bin/ARG_ARCH/ARG_BIN /ARG_BIN
 
 USER nobody:nobody
-ENTRYPOINT ["/myapp"]
+ENTRYPOINT ["/ARG_BIN"]

Makefile

@@ -30,7 +30,21 @@ ARCH ?= amd64
 
 SRC_DIRS := cmd pkg # directories which hold app source (not vendored)
 
-ALL_ARCH := amd64 arm arm64 ppc64le # TODO: base image for non-x86 archs?
+ALL_ARCH := amd64 arm arm64 ppc64le
+
+# Set default base image dynamically for each arch
+ifeq ($(ARCH),amd64)
+    BASEIMAGE?=alpine
+endif
+ifeq ($(ARCH),arm)
+    BASEIMAGE?=armel/busybox
+endif
+ifeq ($(ARCH),arm64)
+    BASEIMAGE?=aarch64/busybox
+endif
+ifeq ($(ARCH),ppc64le)
+    BASEIMAGE?=ppc64le/busybox
+endif
 
 IMAGE := $(REGISTRY)/$(BIN)-$(ARCH)
 
@@ -81,6 +95,7 @@ bin/$(ARCH)/$(BIN): build-dirs
 	    -v $$(pwd)/.go:/go                                                 \
 	    -v $$(pwd):/go/src/$(PKG)                                          \
 	    -v $$(pwd)/bin/$(ARCH):/go/bin                                     \
+	    -v $$(pwd)/bin/$(ARCH):/go/bin/$$(go env GOOS)_$(ARCH)             \
 	    -v $$(pwd)/.go/std/$(ARCH):/usr/local/go/pkg/linux_$(ARCH)_static  \
 	    -w /go/src/$(PKG)                                                  \
 	    $(BUILD_IMAGE)                                                     \
@@ -94,8 +109,13 @@ bin/$(ARCH)/$(BIN): build-dirs
 DOTFILE_IMAGE = $(subst /,_,$(IMAGE))-$(VERSION)
 
 container: .container-$(DOTFILE_IMAGE) container-name
-.container-$(DOTFILE_IMAGE): bin/$(ARCH)/$(BIN) Dockerfile
-	@docker build -t $(IMAGE):$(VERSION) --build-arg ARCH=$(ARCH) .
+.container-$(DOTFILE_IMAGE): bin/$(ARCH)/$(BIN) Dockerfile.in
+	@sed \
+	    -e 's|ARG_BIN|$(BIN)|g' \
+	    -e 's|ARG_ARCH|$(ARCH)|g' \
+	    -e 's|ARG_FROM|$(BASEIMAGE)|g' \
+	    Dockerfile.in > .dockerfile-$(ARCH)
+	@docker build -t $(IMAGE):$(VERSION) -f .dockerfile-$(ARCH) .
 	@docker images -q $(IMAGE):$(VERSION) > $@
 
 container-name:
@@ -133,7 +153,7 @@ build-dirs:
 clean: container-clean bin-clean
 
 container-clean:
-	rm -rf .container-* .push-*
+	rm -rf .container-* .dockerfile-* .push-*
 
 bin-clean:
 	rm -rf .go bin

README.md

@@ -16,19 +16,23 @@ Makefile:
    - change `REGISTRY` to the Docker registry you want to use
    - maybe change `SRC_DIRS` if you use some other layout
 
-Dockerfile:
-   - change all `myapp` to your binary name
+Dockerfile.in:
+   - change the `MAINTAINER` to you
+   - maybe change or remove the `USER` if you need
 
 ## Building
 
 Run `make` or `make build` to compile your app.  This will use a Docker image
 to build your app, with the current directory volume-mounted into place.  This
-will store incremental state for the fastest possible build.
+will store incremental state for the fastest possible build.  Run `make
+all-build` to build for all architectures.
 
 Run `make container` to build the container image.  It will calculate the image
 tag based on the most recent git tag, and whether the repo is "dirty" since
-that tag (see `make version`).
+that tag (see `make version`).  Run `make all-container` to build containers
+for all architectures.
 
-Run `make push` to push the container image to `REGISTRY`.
+Run `make push` to push the container image to `REGISTRY`.  Run `make all-push`
+to push the container images for all architectures.
 
 Run `make clean` to clean up.