Docker deb cache
# host
apt-get install apt-cacher-ng
# dockerfile
ARG APT_CACHE
RUN [ ! -z "$APT_CACHE" ] && echo "Acquire::http::Proxy \"http://$APT_CACHE\";" > /etc/apt/apt.conf.d/30proxy ||:
# docker build
docker build --build-arg APT_CACHE=$HOST_IP:3142 .