I. Do not push to the master branch

The idea is that we want the master branch to contain the main code for our project. Even if we work on our own, it might be a good idea to always push to a different branch, and then integrate the code to the main branch through a pull request (PR). That way we can introduce various checks on pull requests, and impose structure on them. Let’s see how we can do it in GitHub.

I create an empty repository to illustrate how one sets up a CI/CD pipeline step by step.

https://github.com/olegpolivin/Fizz-Buzz-CI-CD

So far it only contains a README.md file. It also has only one main branch, and nothing else. I clone it locally:

git clone https://github.com/olegpolivin/Fizz-Buzz-CI-CD.git

Rules for branches

As usual I can work on the code, and then push to the main branch. That’s what I want to prohibit. Go to the Settings menu for a given repo and choose Branches:

_images/02_setting_branches_selected.png

There are two ways to prevent pushing to the main branch, and you can choose it in the Add rule section:

1. Require pull request reviews before merging. As it is written below:

When enabled, all commits must be made to a non-protected branch and submitted via a pull request with the required number of approving reviews and no changes requested before it can be merged into a branch that matches this rule.

However, indeed, this will prevent you from pushing to main branch, but you cannot be a reviewer of your own pull request as of November 2020. Therefore, if you are working on a project alone, this won’t let you merge PR into your main branch.

There is a different way which is setting up a CI/CD pipeline. Click on Add rule. Here is the rule that I’ve added:

_images/03_branch_rule_status.png

In particular, I’ve added:

  • Require status checks to pass before merging (+ Require branches to be up to date before merging).

    • So far there are none, but we will add them later

  • Include administrators.

    • Even if we are alone on the project we don’t want to allow ourselves to push to main.

Now how can one set up a CI/CD pipeline, so as to prevent pushing to the main?

See II. Continuous Integration / Continuous Delivery section.