**Course Title:** Version Control Systems: Mastering Git **Section Title:** Integrating Git with Development Tools **Topic:** Set up a Git hook for automated tasks in your project.(Lab topic) **Introduction** Git hooks are a powerful feature in Git that allows you to execute custom scripts during various events in the Git workflow. These events can include pre-commit, post-commit, pre-push, and others. Git hooks can be used to automate tasks such as code formatting, testing, and validation. In this lab topic, we will explore how to set up a Git hook for automated tasks in your project. **What are Git Hooks?** Git hooks are scripts that run automatically at specific points during the Git workflow. They can be used to enforce certain rules or validate changes before they are committed or pushed. There are two types of Git hooks: 1. Client-side hooks: These hooks are run on the client-side, i.e., on the developer's machine. They are typically used for tasks such as code formatting and testing. 2. Server-side hooks: These hooks are run on the server-side, i.e., on the remote repository. They are typically used for tasks such as validation and authentication. **Types of Git Hooks** There are several types of Git hooks, each with its own purpose: 1. `pre-commit`: Runs before a commit is made. 2. `post-commit`: Runs after a commit is made. 3. `pre-push`: Runs before a push is made to the remote repository. 4. `post-merge`: Runs after a merge is made. 5. `post-rewrite`: Runs after a rewrite is made. **Setting up a Git Hook** To set up a Git hook, you need to create a script with the desired functionality and place it in the `.git/hooks` directory of your repository. The script should have the same name as the hook type. Here is an example of a simple `pre-commit` hook that checks for any trailing whitespace: ```bash #!/bin/sh echo "Checking for trailing whitespace..." git diff --cached --name-only | while read file; do if [ -n "$(git grep -I -c ' +' "$file")" ]; then echo "Error: Trailing whitespace found in $file" exit 1 fi done ``` **Lab Exercise: Create a `pre-commit` Hook** Create a new Git repository and add a file named `example.txt`. Then, create a `pre-commit` hook that checks for any trailing whitespace. Run the following command to create the hook: ```bash echo "#!/bin/sh" > .git/hooks/pre-commit echo "echo Checking for trailing whitespace... && git diff --cached --name-only | while read file; do if [ -n \"$(git grep -I -c ' +' \"$file\")\" ]; then echo Error: Trailing whitespace found in $file; exit 1; fi; done" >> .git/hooks/pre-commit chmod +x .git/hooks/pre-commit ``` Now, try to commit a file with trailing whitespace. The hook should prevent the commit from happening. **Tips and Best Practices** Here are some tips and best practices for using Git hooks: * Use Git hooks to automate repetitive tasks. * Keep your hooks simple and focused on a single task. * Test your hooks thoroughly to ensure they are working correctly. * Use the `--no-verify` option to skip hooks when committing. **External Resources:** * [Git Hooks Documentation](https://git-scm.com/book/en/v2/Customizing-Git-Git-Hooks) * [Git Hooks Tutorial by GitHub](https://help.github.com/en/github/using-git/using-git-hooks) **Conclusion:** In this lab topic, we have explored how to set up a Git hook for automated tasks in your project. We have learned about the different types of Git hooks and how to create a simple `pre-commit` hook to check for trailing whitespace. With this knowledge, you should be able to automate tasks in your own projects using Git hooks. **Questions or Need Help?** If you have any questions or need help with setting up a Git hook, please leave a comment below.