agrozyme/alpine repository overview

⁠Summary

Source: https://gitlab.com/agrozyme-docker/alpine⁠

Alpine Base Image

⁠Packages

• ruby
• tini-static
• su-exec
• bash
• patch
• git

⁠Environment Variables

• DOCKER_CORE_UID
• DOCKER_CORE_GID

⁠Core User

• Run the container with the root user
• Run the service in the container with the core user
• Simply map the host OS user by setting environment variables DOCKER_CORE_UID / DOCKER_CORE_GID
  • default UID: 500
  • default GID: 500
• Use the ruby gem docker_core to call update_user to change UID / GID of core using the environment variable DOCKER_CORE_UID / DOCKER_CORE_GID
• If the service can not be run as a custom user, it can use su-exec core to execute the service

⁠Docker Build

Dockerfile example

FROM docker.io/library/alpine

RUN apk add --no-cache bash sudo ruby-rdoc ruby-bundler
COPY rootfs /

RUN sudo chmod +x /usr/local/bin/* \
#  && gem install -N thor \
  && gem install -N docker_core \
  && /usr/local/bin/docker_build.rb

SHELL [ "/bin/bash", "-c" ]
ENTRYPOINT ["/sbin/tini-static", "--"]
CMD ["/bin/bash"]

⁠/usr/local/bin/image

• Put custom ruby module scripts here
• Add the statement require_relative("./image/#{module}") to other scripts (ex: docker_build.rb / docker_run.rb)

⁠/usr/local/bin/docker_build.rb

• The docker build script
• Add the statement RUN chmod +x /usr/local/bin/* && gem update -N docker_core && gem clean && /usr/local/bin/docker_build.rb to Dockerfile

Example

#! /usr/bin/ruby

def main
  print(`apk add --no-cache su-exec tini-static busybox-suid`)
end

main

⁠Docker Run

⁠/usr/local/bin/docker_run.rb

• The docker run script
• Add the statement CMD ["/usr/local/bin/docker_run.rb"] to Dockerfile

Example

#! /usr/bin/ruby

def main
  exec('/bin/bash')
end

main

⁠/usr/local/bin

• Put the command binary / script here
• Use docker run -it --rm {image} {command} to execute the command

⁠Host scripts

• Run at host OS or VM
• See https://gitlab.com/agrozyme-package/ruby/docker_command⁠ example/stack folder

⁠Docker Files Layout

/home/core/deploy
|-- profile.sh
|-- runner.rb
|-- <core>
|-- <volume>
|-- <stack>
    |-- docker-compose.yml
    |-- [setup.sh]
    |-- [*.env]

⁠Kubernetes Files Layout

/home/core/deploy
|-- profile.sh
|-- runner.rb
|-- <core>
|-- <volume>
|-- <stack>
    |-- kustomization.yml
    |-- volume.yml
    |-- issuer.yml
    |-- deployment.yml
    |-- [setup.sh]
    |-- [*.env]

⁠Prepare

• If the core user does not exist in the host OS, create one
• It is recommended to set the uid / gid of the core user to 500
• The example files in the host folder need to be placed in the /home/core/deploy directory
• install ruby (version 2.5+)
• install docker_core gem
• clone https://gitlab.com/agrozyme-package/ruby/docker_command⁠ and change for your needs
• copy deploy folder to /home/core/deploy in host OS or VM

⁠Commands

• update_core: update gem docker_core
• update_alias: update alias
• update_swarm [orchestrator]: update default orchestrator
• swarm_run: run command
• swarm_status: show swarm service status
• swarm_setup: setup the swarm
• swarm_leave: clean everything up and leave the swarm
• stack_deploy: delpoy stack
• stack_remove: remove stack and containers

⁠Gitlab CI

• Build a multi-platform docker image and push it to Docker Hub⁠
• Use podman-qemu⁠ to build