docker mirror packages repo

Allows to simulate upstream centos / ubuntu / opensuse package repository servers by using a docker container which contains a local package mirror.

The scripts in this project allow to build a local package mirror using rsync. When ready the rpm/deb packages get copied into a docker image which has a small web script that mimics the mirrorlist function of the original upstream package repository servers.

There is a helper script docker_mirror which can start a mirror docker image as container. The --add-hosts option prints the line for "docker run" so that calls to the original upstream package server get diverted to the ip address of the locally running docker container.

Effectively all "yum install" or "zypper install" or "apt-get install" commands run locally in the docker network. No internet access required. Without changing repo files. Without special proxy host setups. This is faster, allows for reproducible install tests, and it can be used in a disconnected environment.

The scripting has also been used with docker-compose and ansible deployment setups. Over the years a number of package repos have been tested - starting with distros from 2016 until today. Even when the upstream package repositories get disabled, for being out of support, the local docker mirrors continue to work.