Git Hooks and Automation

What You’ll Learn 📚

• Understand what Git hooks are and why they’re useful
• Learn how to set up and use Git hooks with simple examples
• Explore progressively complex examples to automate tasks
• Common questions and troubleshooting tips

Introduction to Git Hooks

Git hooks are scripts that Git executes before or after events such as commit, push, and receive. They allow you to automate tasks and enforce rules in your workflow. Think of them as little helpers that make sure everything runs smoothly. 🚀

Key Terminology

• Hook: A script that runs automatically when a specific Git event occurs.
• Pre-commit: A hook that runs before a commit is finalized.
• Post-commit: A hook that runs after a commit is completed.

Getting Started with Git Hooks

Simple Example: Pre-commit Hook

#!/bin/sh # This is a simple pre-commit hook that checks for TODO comments in your code. if grep -r 'TODO' .; then echo 'Please resolve TODOs before committing!' exit 1 fi

How to Set Up

1. Navigate to your Git project’s .git/hooks directory.
2. Create a file named pre-commit (no extension).
3. Copy the script above into the file.
4. Make the script executable:

   chmod +x .git/hooks/pre-commit

Progressively Complex Examples

Example 1: Post-commit Hook

#!/bin/sh # This post-commit hook sends a notification after a successful commit. echo 'Commit successful! 🎉'

Example 2: Pre-push Hook

#!/bin/sh # This pre-push hook checks for linting errors before pushing. npm run lint if [ $? -ne 0 ]; then echo 'Linting errors found. Push aborted! ❌' exit 1 fi

Example 3: Custom Hook for Code Formatting

#!/bin/sh # This custom hook formats code before committing. npm run format

Common Questions and Answers

1. What are Git hooks?

   Git hooks are scripts that run automatically at specific points in your Git workflow, allowing you to automate tasks.

2. How do I create a Git hook?

   Create a script in the .git/hooks directory of your project and make it executable.

3. Can I have multiple hooks for the same event?

   Yes, you can chain scripts together within a single hook file.

4. Why isn’t my hook running?

   Ensure the hook script is executable and located in the correct directory.

Troubleshooting Common Issues

Ensure your hook scripts are executable by running chmod +x on them.

If your hooks aren’t running, check the file paths and permissions. Hooks must be in the .git/hooks directory and have the correct name.

Practice Exercises

• Create a pre-commit hook that checks for console.log statements in your JavaScript code.
• Write a post-merge hook that sends a notification when a merge is completed.

Remember, practice makes perfect! Keep experimenting with different hooks to see what works best for your workflow. 💪

Additional Resources

• Official Git Hooks Documentation
• Pre-commit Framework