Compile Go code with docker run not docker build

Go code is really fast to compile so we do not really need to use the
cache features of `docker build`. So make a compile container instead.
This can also output a build context and Dockerfile if you want to do
a build.

For reference, an uncached `docker build` of our Go code takes about
7s, a cached one 1.2s, and this takes 1.7s, so the best case is a little
worse, but we save a lot of images, and the worst case is better.

This is mainly designed to make the nested builds for containerd
containers simpler too. Will add a variant for the C code as well.

Also add `-static` to the flags so we always make static executables,
which was omitted previously.

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

alpine/base/go-compile/Dockerfile

@@ -0,0 +1,8 @@
+FROM golang:1.7-alpine
+RUN apk update && apk add --no-cache build-base git
+
+RUN go get -u github.com/golang/lint/golint
+
+COPY lint.sh compile.sh /usr/bin/
+
+ENTRYPOINT ["/usr/bin/compile.sh"]

alpine/base/go-compile/Makefile

@@ -0,0 +1,29 @@
+.PHONY: tag push
+
+BASE=golang:1.7-alpine
+IMAGE=go-compile
+
+default: push
+
+hash: Dockerfile lint.sh compile.sh
+	DOCKER_CONTENT_TRUST=1 docker pull $(BASE)
+	tar cf - $^ | docker build --no-cache -t $(IMAGE):build -
+	docker run --rm --entrypoint=/bin/sh $(IMAGE):build -c 'cat /usr/local/go/bin/go /lib/apk/db/installed /usr/bin/lint.sh /go/bin/golint /usr/bin/compile.sh | sha1sum' | sed 's/ .*//' > hash
+
+push: hash
+	docker pull mobylinux/$(IMAGE):$(shell cat hash) || \
+		(docker tag $(IMAGE):build mobylinux/$(IMAGE):$(shell cat hash) && \
+		 docker push mobylinux/$(IMAGE):$(shell cat hash))
+	docker rmi $(IMAGE):build
+	rm -f hash
+
+tag: hash
+	docker pull mobylinux/$(IMAGE):$(shell cat hash) || \
+		docker tag $(IMAGE):build mobylinux/$(IMAGE):$(shell cat hash)
+	docker rmi $(IMAGE):build
+	rm -f hash
+
+clean:
+	rm -f hash
+
+.DELETE_ON_ERROR:

alpine/base/go-compile/compile.sh

@@ -0,0 +1,59 @@
+#!/bin/sh
+
+# This is designed to compile a single package to a single binary
+# so it makes some assumptions about things to simplify config
+# to output a single binary (in a tarball) just use -o file
+# use --docker to output a tarball for input to docker build -
+
+set -e
+
+usage() {
+	echo "Usage: -o file [--docker]"
+	exit 1
+}
+
+[ $# = 0 ] && usage
+
+while [ $# -gt 1 ]
+do
+	flag="$1"
+	case "$flag" in
+	-o)
+		out="$2"
+		mkdir -p "$(dirname $2)"
+		shift
+	;;
+	*)
+		echo "Unknown option $1"
+		exit 1
+	esac
+	shift
+done
+
+[ $# -gt 0 ] && [ $1 = "--docker" ] && DOCKER=1 && shift
+
+[ $# -gt 0 ] && usage
+[ -z "$out" ] && usage
+
+package=$(basename "$out")
+
+dir="$GOPATH/src/$package"
+
+mkdir -p $dir
+
+# untar input
+tar xf - -C $dir
+
+/usr/bin/lint.sh $dir
+
+go build -o $out --ldflags '-extldflags "-fno-PIC -static"' "$package"
+
+if [ -z "$DOCKER" ]
+then
+	tar cf - $out
+	exit 0
+fi
+
+printf "FROM scratch\nCOPY $out $out\nENTRYPOINT [\"$out\"]\n" > Dockerfile
+
+tar cf - Dockerfile $out

alpine/base/go-compile/lint.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+set -e
+
+cd $1
+
+>&2 echo "gofmt..."
+test -z $(gofmt -s -l .| grep -v .pb. | grep -v */vendor/ | tee /dev/stderr)
+
+>&2 echo "govet..."
+test -z $(go tool vet -printf=false . 2>&1 | grep -v */vendor/ | tee /dev/stderr)
+
+>&2 echo "golint..."
+test -z $(find . -type f -name "*.go" -not -path "*/vendor/*" -not -name "*.pb.*" -exec golint {} \; | tee /dev/stderr)
+
+>&2 echo "Successful lint check!"

alpine/packages/diagnostics/Dockerfile

@@ -1,12 +0,0 @@
-# Tag: 2c9434f1c4ff70b102f34a97d2df1a8363a11a65
-FROM mobylinux/alpine-build-go@sha256:d528bbf7102e4209bd59ef030d41de9003ab8e42c303956f62b2df47f3e17849
-
-COPY ./ /go/src/diagnostics-server/
-
-WORKDIR /go/src/diagnostics-server
-
-RUN lint.sh .
-
-RUN go install --ldflags '-extldflags "-fno-PIC"'
-
-CMD ["tar", "cf", "-", "-C", "/go/bin", "diagnostics-server"]

alpine/packages/diagnostics/Makefile

@@ -1,12 +1,13 @@
-all: usr/bin/diagnostics-server
+# Tag: 470f68ec32e016484fb8e0bcc2f06cd3f201ea68
+GO_COMPILE=mobylinux/go-compile@sha256:b723c0e95a6293300392e57d6ab52574f9217e2410b390a24cbfc4f9070edb6b
 
-DEPS=Dockerfile $(wildcard *.go)
+default: usr/bin/diagnostics-server
+
+DEPS=$(wildcard *.go)
 
 usr/bin/diagnostics-server: $(DEPS) ../vendor/manifest
-	BUILD=$$( tar cf - $(DEPS) -C .. vendor | docker build -q - ) && \
+	mkdir -p $(dir $@)
-	[ -n "$$BUILD" ] && \
+	tar cf - $(DEPS) -C .. vendor | docker run --rm --net=none --log-driver=none -i $(GO_COMPILE) -o $@ | tar xf -
-	echo "Built $$BUILD" && \
-	docker run --rm --net=none $$BUILD | tar xf - -C usr/bin
 
 clean:
 	rm -f usr/bin/diagnostics-server

alpine/packages/proxy/Makefile

@@ -1,12 +1,12 @@
+# Tag: 470f68ec32e016484fb8e0bcc2f06cd3f201ea68
+GO_COMPILE=mobylinux/go-compile@sha256:b723c0e95a6293300392e57d6ab52574f9217e2410b390a24cbfc4f9070edb6b
+
 all: usr/bin/slirp-proxy sbin/proxy-vsockd
 
 DEPS=Dockerfile $(wildcard *.go libproxy/*.go)
 
 proxy: $(DEPS) ../vendor/manifest
-	BUILD=$$( tar cf - $(DEPS) -C .. vendor | docker build -q - ) && \
+	tar cf - $(DEPS) -C .. vendor | docker run --rm --net=none --log-driver=none -i $(GO_COMPILE) -o $@ | tar xf -
-	[ -n "$$BUILD" ] && \
-	echo "Built $$BUILD" && \
-	docker run --rm --net=none $$BUILD | tar xf -
 
 usr/bin/slirp-proxy: proxy
 	mkdir -p usr/bin

alpine/packages/vsudd/Dockerfile

@@ -1,12 +0,0 @@
-# Tag: 2c9434f1c4ff70b102f34a97d2df1a8363a11a65
-FROM mobylinux/alpine-build-go@sha256:d528bbf7102e4209bd59ef030d41de9003ab8e42c303956f62b2df47f3e17849
-
-COPY ./ /go/src/vsudd/
-
-WORKDIR /go/src/vsudd
-
-RUN lint.sh .
-
-RUN go install --ldflags '-extldflags "-fno-PIC"'
-
-CMD ["tar", "cf", "-", "-C", "/go/bin", "vsudd"]

alpine/packages/vsudd/Makefile

@@ -1,13 +1,13 @@
-all: vsudd
+# Tag: 470f68ec32e016484fb8e0bcc2f06cd3f201ea68
+GO_COMPILE=mobylinux/go-compile@sha256:b723c0e95a6293300392e57d6ab52574f9217e2410b390a24cbfc4f9070edb6b
 
-DEPS=Dockerfile $(wildcard *.go)
+default: sbin/vsudd
 
-vsudd: $(DEPS) ../vendor/manifest
+DEPS=$(wildcard *.go)
-	mkdir -p sbin
+
-	BUILD=$$( tar cf - $(DEPS) -C .. vendor | docker build -q - ) && \
+sbin/vsudd: $(DEPS) ../vendor/manifest
-	[ -n "$$BUILD" ] && \
+	mkdir -p $(dir $@)
-	echo "Built $$BUILD" && \
+	tar cf - $(DEPS) -C .. vendor | docker run --rm --net=none --log-driver=none -i $(GO_COMPILE) -o $@ | tar xf -
-	docker run --rm --net=none $$BUILD | tar xf - -C sbin
 
 clean:
 	rm -rf sbin