Automating with Git Hooks

In a professional environment like CodeHarborHub, we want to ensure that the code we share is always high quality. We don't want to manually check for typos, formatting errors, or broken tests every single time.

Git Hooks are scripts that Git executes automatically when specific actions happen—like committing, pushing, or receiving code.

What are Git Hooks?

Think of a Git Hook as a Security Guard standing at the entrance of your repository.

• When you try to commit, the guard checks if you formatted your code correctly.
• When you try to push, the guard checks if all your tests pass.
• If the guard finds an error, they block the action until you fix it.

The Two Types of Hooks

Type	Location	Use Case
Client-Side	Your PC	Checks code style (Linting), runs local tests, checks commit messages.
Server-Side	GitHub/Cloud	Enforces branch permissions, triggers "Deployment" to a website.

Common Hooks at CodeHarborHub

1. Pre-commit Hook

This runs before you are even allowed to create a commit.

• The Goal: Catch small mistakes early.
• Example: It can automatically run Prettier to fix your code formatting so you don't have to think about it.

2. Pre-push Hook

This runs before your code is sent to GitHub.

• The Goal: Prevent "Breaking the Build."
• Example: It runs your entire test suite. If a single test fails, the push is cancelled, preventing you from sending broken code to your teammates.

Where are Hooks stored?

Every Git project has a hidden folder called .git/hooks. If you look inside, you will see several sample files (like pre-commit.sample). To activate a hook, you simply remove the .sample extension and add your script.

Modern Tooling: Husky

Writing raw shell scripts for hooks can be difficult. At CodeHarborHub, we recommend using a tool called Husky (for JavaScript/Node projects). It makes managing hooks as easy as editing your package.json.

# Example: Adding a pre-commit hook with Husky
npx husky add .husky/pre-commit "npm test"

Now, every time you run git commit, your tests will run automatically!

Industrial Best Practices

1. Don't Overdo It: If your hooks take 10 minutes to run, you will start hating the commit command. Keep hooks fast!

2. Shared Hooks: Ensure your team uses the same hooks so everyone follows the same code style.

3. The "Emergency Escape": If you absolutely MUST commit something and skip the hooks (e.g., a tiny typo fix in a README), you can use the "no-verify" flag:

   git commit -m "fix: tiny typo" --no-verify

tip

Git Hooks are stored locally in the .git folder, which is not pushed to GitHub. To share hooks with your team, use a tool like Husky or pre-commit (Python) which stores the configuration in your project files!