Contributing to Open Source Projects

Various open source projects use different tools for managing distributed development, bust most use the same set of concepts:

• Version Control (with central remote repository)
• Pull Requests
• Isolated Dev/Test environment
• Continuous Integration

Suggested Workflow

1. Clone the repository. Run setup.
2. Make a feature branch based on latest master.
3. Make changes
4. Commit changes to local branch
5. Push commits to a remote version of your feature branch
6. Make Pull Request for your branch
7. Make changes and repackage changes into new set of commits. Don't push to the remote feature branch, keep the history.
8. Ship it, undeployed commits should not sit in the master branch on GitHub. Critical code is run through a CI anyways.

Deployment Cycle

1. Git Merge
2. Build image (Container Build in Docker)
3. Automation Testing (fast because of buildkite)
   • for test failing, tests locally
4. Deploy

Version Control

Is an integral part of open source projects. Includes git, svn, and mercurial. I use git. Github and Bitbucket host central repositories for developers to contribute to. More on Git.

The following steps can be followed as an example for contributing to Rails:

• git clone https://github.com/rails/rails.git clone repo
• git checkout -b my_new_branch create new branch for local changes
• bundle install install dependencies and gems
• bundle exec rails new ~/my-test-app --dev creates dummy application to test changes. --dev uses your branch
• bundle exec rake test in a specific file will run tests for a component

Pull Requests

After making changes to a repository, a pull request is made, requesting that code changes are merged to the central repository. After your changes are in a forked repository. It is good practice to squash commits into one commit, using git rebase.

More on Pull Requests

Isolated Dev/Test environments

Projects often have a standardized developer environment for core development, using a DevOps tool like Docker or Vagrant, for various cases.

Continuous Integration

Is the practice in software engineering, of merging all developer working copies with a shared main branch. CI often refers to testing every change after being merged. Travis CI is a very popular option for continuous integration.