An intro to contributing to a 3rd party repo for beginners

An opinionated and probably oversimplified guidelines. Please, feel free challenging in comments.

You will find visualized what's this article is above in Google Slides.

Pre-requisites

You know and use basic git commands like init, clone, add, commit, branch, checkout, merge, pull, push.

You probably know and use git commands like fetch, pull --rebase, rebase, cherry-pick.

You want to contribute to a repo you do not have write access to.

You do not know how to or do not feel confident working with repos you do not have write access to.

You do not follow any firm workflow working with your own repos or repos you do not have write access to.

What you will learn

• How to keep your fork in sync with a source repo
• How to minimize risks of conflicts
• How to keep your repo history tree as clean as possible
• How to contribute properly via pull requests

A good workflow to start with

Some definitions:

• upstream is a repo you want to contribute to
• origin or fork is your own fork of an upstream
• local is a local clone of origin

Initialize things

1. Fork an upstream. On GitHub navigate to the upstream and click Fork button.
2. git clone origin-url.git target-directory on your machine to clone your fork
3. cd target-directory
4. git remote add upstream-url.git to enable upstream-related actions

Add your changes

It is important to have your fork in sync with upstream, employ branches and follow certain workflow to minimize conflicts risks and keep the history tree as clean as possible.

Initialize a feature branch

1. sync local and origin with upstream git checkout master && git pull upstream master && git push origin master
2. create a feature branch with a meaningful name git checkout -b feature-branch

There are many branch naming conventions. Few to mention are:

• start with author initials so other collaborators know who initialized the branch and also find branches per author, e.g. or-feature-portview
• use slashes to denominate scopes, e.g. feature/api/rest, bugfix/sleep
• use ticket/issue/epic/story id, e.g. feat/epic123/story128/search-people

Useful alias:

git config --global alias.sync-master '!git checkout master && git pull upstream master && git push origin master'

Usage: git sync-master

Feature development cycle

1. do whatever you want
2. commit often: git add . && git commit -m "Add REST api PATCH method"
3. squash eventually grouping commits as appropriate: git rebase -i <REF> (Making use of git rebase)
4. sync eventually local, origin, and feature branch with upstream
   • git checkout master && git pull upstream master && git push origin master
   • git checkout - && git merge master
   • resolve conflicts using your IDE or command line
   • when done git add . && gir commit -m "Resolved merge conflict by incorporating both suggestions"
   • see also Resolving a merge conflict using the command line
5. go to #1
6. eventually push to origin: git push origin feature-branch

Useful alias:

git config --global alias.sync-branch '!git sync-master && git checkout - && git merge master'

Usage: git sync-branch (it also does sync-master as a part of the flow)

Commit message

There are numbers of commit message structure conventions.
To mention a few:

• start with commit scope, e.g. one of feat|fix|docs|style|refactor|test|chore
• add feature/fix scope, e.g. (api)
• use imperative mood in the subject line, e.g. one of Add|Change|Fix|Refactor|Remove|Bump version|Release version

If you resolve an issue (in upstream or fork) it is useful to have a note on issue resolution.

Your commit message may look like the following

fix(foo api): Fix ABC component render conditions

Resolves: #12
See also: #34, #78

Further reading:

• Conventional Commits 1.0.0-beta.2
• How to Write a Git Commit Message
• 5 Useful Tips For A Better Commit Message
• Semantic release
• even more...

DON'Ts

Do not squash or rebase what is already on remotes!

Do not overwrite hsitory on remotes!

NB

The above doesn't cover the case when you work on the same branch with someone else, when you will prefer git pull --rebase over git pull.

Contribute via pull request

Contributing is not necessarily required. You may develop your fork for your own purposes (adhering to upstream license conditions).

Otherwise stick to the following contribution workflow:

1. git push origin feature-branch to push your feature branch to the origin.
2. Navigate to the cloud git hub (e.g. GitHub)
3. Use cloud UI to create the PR
4. Pass through code review process until your changes are merged or declined

Once your feature branch gets merged you will find your commits in upon next sync with upstream. So, you don't need merging those to your master locally.

However, you will need to merge into master if you do not contribute to the upstream or your PR is declined and you want to keep those for yourself.

Cleaning up

Once your PR approved and merged you can get rid off your feature branch.

git branch -D feature-branch

Feel free forking the source gist and editing it so it fits your particular needs (e.g. remove parts that you already know well).