Description

A repo to build Ruby container. The container image only contains essential apt package. For dated Ruby (< 2.4.0) that is built on top of recent ubuntu release (>= 20.04), some ruby version manager like rvm will be used as there will be build error due to package incompatibility when we build Ruby from scratch.

Currently support the following versions:

1. ruby-231 on ubuntu 20.04

Things to note

1. For Ruby containers that rely on RVM, login bash command is required should you want to run any Ruby command in an non-interactive shell session. In fact, this is the most common run pattern as most Ruby processes are started by doing bundle exec rails server or bundle exec sidekiq start and etc during deployment. These commands will not work in RVM managed Ruby unless you fired it in this fashion, bash -lc "bundle exec sidekiq start". This is due to the fact that RVM Ruby version selector is implemented as a bash function and it will be loaded from the .bash_profile under login shell session. So if your Ruby process is required to be run under different user (other than root), please check if the dedicated user can invoke the rvm function after login.

Branching strategy

As we are managing different flavours of Ruby in a single repo, we will be managing those flavours using branch name.

Say we want to create a Ruby build for ruby-250-ubuntu2004. The following steps are required:

1. Create a dev branch with sensible name such as ruby-250-ubuntu2004
2. Create a test branch named as test/ruby-250-ubuntu2004
3. Create a master branch named as masters/ruby-250-ubuntu2004
4. Create a PR the dev branch to masters/ruby-250-ubuntu2004
5. Add the new build config to the config file. See CI section for how to configure a CI for a new flavour.
6. Start developing and generate a test build by merging into test/ruby-250-ubuntu2004.
7. Once its tested, merge the PR.
8. Repeat step 1-7 if you need to deliver more patch to the same flavour. (config setup only needs to be done once when the flavour is first created)

Image tagging convention

Image tag is constructed by joining all the namespaces with _. Say we want to want a tag to carry the information of ruby version, os version, the tag will be something like ruby-231_ubuntu-2004.

CI

To create a new ruby flavour build, create a properly namespaced directory and put your Dockerfile inside there. You don't have to prepend masters or tests to the branch name as this will be handled during build time.

"ruby-231/ubuntu2004":          # => this is the branch name
  target: "ruby_231/ubuntu2004" # => this is the target path of the Dockerfile
  ruby_version: ruby-231             # => these are the meta info of the container image 
  os_version: ubuntu-2004
  ruby_manager: rvm
  tags:                         # => these are the tags that you want to use for the build image. The values will be extracted from the parent level
    - ruby_version
    - os_version
    - ruby_manager

Automated CI is setup branches with name starting with masters/ or test/. For example, changes in branch masters/foo will trigger new build, but changes in branch foo will not.