Enhance Dockerfile for local building (#1002)

Added a caching layer in the docker build for compiling all of the
vendor dependencies, drops compilation time to about 15s

Added support in Dockerfile for passing BUILD_VERSION and
NIGHTLY_RELEASE to build.sh

Add compile-with-docker target

Split out how we get the git commit SHA so it's reusable for docker
image tag

Dockerfile

@@ -28,14 +28,27 @@ FROM golang:1.7.6
 #ENV https_proxy ""
 ARG http_proxy
 ARG https_proxy
-ENV GOPATH=/go/ NET_CONTAINER_BUILD=1
+
+WORKDIR /go/src/github.com/contiv/netplugin/
 
 ENTRYPOINT ["netplugin"]
 CMD ["--help"]
 
-COPY ./ /go/src/github.com/contiv/netplugin/
+# by far, most of the compilation time is building vendor packages
+# build the vendor dependencies as a separate docker caching layer
+COPY ./vendor/ /go/src/github.com/contiv/netplugin/vendor/
 
-WORKDIR /go/src/github.com/contiv/netplugin/
+RUN GOGC=1500 go install -ldflags "-s -w" $(go list ./vendor/...)
+
+# build the netplugin binaries
+COPY ./ /go/src/github.com/contiv/netplugin/
 
-RUN make build
+ARG BUILD_VERSION=""
+ARG NIGHTLY_RELEASE=""
 
+RUN GOPATH=/go/ \
+    BUILD_VERSION="${BUILD_VERSION}" \
+    NIGHTLY_RELEASE="${NIGHTLY_RELEASE}" \
+    make compile \
+      && cp scripts/contrib/completion/bash/netctl /etc/bash_completion.d/netctl \
+      && netplugin -version

Makefile

@@ -1,5 +1,6 @@
 
-.PHONY: all all-CI build clean default unit-test release tar checks go-version gofmt-src golint-src govet-src
+.PHONY: all all-CI build clean default unit-test release tar checks go-version gofmt-src \
+	golint-src govet-src run-build compile-with-docker
 
 DEFAULT_DOCKER_VERSION := 1.12.6
 SHELL := /bin/bash
@@ -86,23 +87,26 @@ endif
 
 checks: go-version gofmt-src golint-src govet-src misspell-src
 
-run-build: deps checks clean
+compile:
 	cd $(GOPATH)/src/github.com/contiv/netplugin && \
 	NIGHTLY_RELEASE=${NIGHTLY_RELEASE} BUILD_VERSION=${BUILD_VERSION} \
 	TO_BUILD="${TO_BUILD}" VERSION_FILE=${VERSION_FILE} \
 	scripts/build.sh
 
+# fully prepares code for pushing to branch, includes building binaries
+run-build: deps checks clean compile
+
+compile-with-docker:
+	docker build \
+		--build-arg NIGHTLY_RELEASE=${NIGHTLY_RELEASE} \
+		--build-arg BUILD_VERSION=${BUILD_VERSION} \
+		-t netplugin:$${BUILD_VERSION:-devbuild}-$$(./scripts/getGitCommit.sh) .
+
 build-docker-image: start
 	vagrant ssh netplugin-node1 -c 'bash -lc "source /etc/profile.d/envvar.sh && cd /opt/gopath/src/github.com/contiv/netplugin && make host-build-docker-image"'
 
-
-ifdef NET_CONTAINER_BUILD
-install-shell-completion:
-	cp scripts/contrib/completion/bash/netctl /etc/bash_completion.d/netctl
-else
 install-shell-completion:
 	sudo cp scripts/contrib/completion/bash/netctl /etc/bash_completion.d/netctl
-endif
 
 build: start ssh-build stop
 
@@ -116,12 +120,8 @@ update:
 
 # setting CONTIV_NODES=<number> while calling 'make demo' can be used to bring
 # up a cluster of <number> nodes. By default <number> = 1
-ifdef NET_CONTAINER_BUILD
-start:
-else
 start:
 	CONTIV_DOCKER_VERSION="$${CONTIV_DOCKER_VERSION:-$(DEFAULT_DOCKER_VERSION)}" CONTIV_NODE_OS=${CONTIV_NODE_OS} vagrant up
-endif
 
 # ===================================================================
 #kubernetes demo targets
@@ -195,26 +195,17 @@ mesos-cni-destroy:
 demo-ubuntu:
 	CONTIV_NODE_OS=ubuntu make demo
 
-ifdef NET_CONTAINER_BUILD
-stop:
-else
 stop:
 	CONTIV_NODES=$${CONTIV_NODES:-3} vagrant destroy -f
-endif
 
 demo: ssh-build
 	vagrant ssh netplugin-node1 -c 'bash -lc "source /etc/profile.d/envvar.sh && cd /opt/gopath/src/github.com/contiv/netplugin && make host-restart host-swarm-restart"'
 
 ssh:
 	@vagrant ssh netplugin-node1 -c 'bash -lc "cd /opt/gopath/src/github.com/contiv/netplugin/ && bash"' || echo 'Please run "make demo"'
 
-ifdef NET_CONTAINER_BUILD
-ssh-build:
-	cd /go/src/github.com/contiv/netplugin && make run-build install-shell-completion
-else
 ssh-build: start
 	vagrant ssh netplugin-node1 -c 'bash -lc "source /etc/profile.d/envvar.sh && cd /opt/gopath/src/github.com/contiv/netplugin && make run-build install-shell-completion"'
-endif
 
 unit-test: stop clean
 	./scripts/unittests -vagrant

scripts/build.sh

@@ -15,15 +15,7 @@ else
 	BUILD_VERSION="$VERSION-$BUILD_TIME"
 fi
 
-if command -v git &>/dev/null && git rev-parse &>/dev/null; then
-	GIT_COMMIT=$(git rev-parse --short HEAD)
-	if [ -n "$(git status --porcelain --untracked-files=no)" ]; then
-		GIT_COMMIT="$GIT_COMMIT-unsupported"
-	fi
-else
-	echo >&2 'error: unable to determine the git revision'
-	exit 1
-fi
+GIT_COMMIT=$(./scripts/getGitCommit.sh)
 
 echo $BUILD_VERSION >$VERSION_FILE
 
@@ -32,4 +24,4 @@ GOGC=1500 go install \
 	-X $PKG_NAME.buildTime=$BUILD_TIME \
 	-X $PKG_NAME.gitCommit=$GIT_COMMIT \
 	-s -w" \
-	-v $TO_BUILD
+	$TO_BUILD

scripts/getGitCommit.sh

@@ -0,0 +1,14 @@
+#!/bin/bash
+
+set -euo pipefail
+
+if command -v git &>/dev/null && git rev-parse &>/dev/null; then
+    GIT_COMMIT=$(git rev-parse --short HEAD)
+    if [ -n "$(git status --porcelain --untracked-files=no)" ]; then
+        GIT_COMMIT="$GIT_COMMIT-unsupported"
+    fi
+    echo $GIT_COMMIT
+    exit 0
+fi
+echo >&2 'error: unable to determine the git revision'
+exit 1