Merge pull request #9804 from tianon/dockerfile-tweaks

Adjust Dockerfile style to be more consistent

Dockerfile

@@ -52,12 +52,14 @@ RUN	apt-get update && apt-get install -y \
 	--no-install-recommends
 
 # Get lvm2 source for compiling statically
-RUN	git clone --no-checkout https://git.fedorahosted.org/git/lvm2.git /usr/local/lvm2 && cd /usr/local/lvm2 && git checkout -q v2_02_103
+RUN git clone -b v2_02_103 https://git.fedorahosted.org/git/lvm2.git /usr/local/lvm2
 # see https://git.fedorahosted.org/cgit/lvm2.git/refs/tags for release tags
-# note: we don't use "git clone -b" above because it then spews big nasty warnings about 'detached HEAD' state that we can't silence as easily as we can silence them using "git checkout" directly
 
 # Compile and install lvm2
-RUN	cd /usr/local/lvm2 && ./configure --enable-static_link && make device-mapper && make install_device-mapper
+RUN cd /usr/local/lvm2 \
+	&& ./configure --enable-static_link \
+	&& make device-mapper \
+	&& make install_device-mapper
 # see https://git.fedorahosted.org/cgit/lvm2.git/tree/INSTALL
 
 # Install Go
@@ -76,7 +78,13 @@ ENV	DOCKER_CROSSPLATFORMS	\
 
 # (set an explicit GOARM of 5 for maximum compatibility)
 ENV GOARM 5
-RUN	cd /usr/local/go/src && bash -xc 'for platform in $DOCKER_CROSSPLATFORMS; do GOOS=${platform%/*} GOARCH=${platform##*/} ./make.bash --no-clean 2>&1; done'
+RUN cd /usr/local/go/src \
+	&& set -x \
+	&& for platform in $DOCKER_CROSSPLATFORMS; do \
+		GOOS=${platform%/*} \
+		GOARCH=${platform##*/} \
+			./make.bash --no-clean 2>&1; \
+	done
 
 # reinstall standard library with netgo
 RUN go clean -i net && go install -tags netgo std
@@ -87,12 +95,6 @@ RUN	go get golang.org/x/tools/cmd/cover
 # TODO replace FPM with some very minimal debhelper stuff
 RUN gem install --no-rdoc --no-ri fpm --version 1.3.2
 
-# Install man page generator
-RUN mkdir -p /go/src/github.com/cpuguy83 \
-    && git clone -b v1 https://github.com/cpuguy83/go-md2man.git /go/src/github.com/cpuguy83/go-md2man \
-    && cd /go/src/github.com/cpuguy83/go-md2man \
-    && go get -v ./...
-
 # Get the "busybox" image source so we can build locally instead of pulling
 RUN git clone -b buildroot-2014.02 https://github.com/jpetazzo/docker-busybox.git /docker-busybox
 
@@ -103,7 +105,11 @@ RUN	curl -sSL -o /cirros.tar.gz https://github.com/ewindisch/docker-cirros/raw/1
 RUN git clone -b 0.7.0 https://github.com/docker/docker-py.git /docker-py
 
 # Setup s3cmd config
-RUN	/bin/echo -e '[default]\naccess_key=$AWS_ACCESS_KEY\nsecret_key=$AWS_SECRET_KEY' > $HOME/.s3cfg
+RUN { \
+		echo '[default]'; \
+		echo 'access_key=$AWS_ACCESS_KEY'; \
+		echo 'secret_key=$AWS_SECRET_KEY'; \
+	} > ~/.s3cfg
 
 # Set user.email so crosbymichael's in-container merge commits go smoothly
 RUN git config --global user.email 'docker-dummy@example.com'
@@ -116,6 +122,14 @@ VOLUME	/var/lib/docker
 WORKDIR /go/src/github.com/docker/docker
 ENV DOCKER_BUILDTAGS apparmor selinux btrfs_noversion
 
+# Install man page generator
+COPY vendor /go/src/github.com/docker/docker/vendor
+# (copy vendor/ because go-md2man needs golang.org/x/net)
+RUN set -x \
+	&& git clone -b v1 https://github.com/cpuguy83/go-md2man.git /go/src/github.com/cpuguy83/go-md2man \
+	&& git clone -b v1.2 https://github.com/russross/blackfriday.git /go/src/github.com/russross/blackfriday \
+	&& go install -v github.com/cpuguy83/go-md2man
+
 # Wrap all commands in the "docker-in-docker" script to allow nested containers
 ENTRYPOINT ["hack/dind"]