FROM docker.jcg.re/base-alpine


ENV GOPATH=/gopath 

ONBUILD ADD plugins.txt /plugins
ONBUILD ARG BRANCH
ONBUILD ARG CLONE_URL=github.com/mholt/caddy
ONBUILD RUN apk upgrade --update \
 && apk add --no-cache -t build-deps \
      build-base \
      libcap \
      go \
      git \
 && mkdir -p ${GOPATH}/src/${CLONE_URL} \
 && cd $GOPATH/src/${CLONE_URL} \
 && git clone https://${CLONE_URL} . \
 && git checkout ${BRANCH:-$(git describe --abbrev=0 --tags)} \
 && cd caddy/caddymain \
 && export LINE="$(grep -n "// This is where other plugins get plugged in (imported)" < run.go | sed 's/^\([0-9]\+\):.*$/\1/')" \
 && head -n ${LINE} run.go > newrun.go \
 && cat /plugins >> newrun.go \
 && line=`expr ${LINE} + 1` \
 && tail -n +${LINE} run.go >> newrun.go \
 && rm -f run.go \
 && mv newrun.go run.go \
 && go get ${CLONE_URL}/... \
 && mv $GOPATH/bin/caddy /usr/bin \
 && setcap cap_net_bind_service=+ep /usr/bin/caddy \
 && apk del --purge build-deps \
 && rm -rf $GOPATH /plugins