Ignore Files - gitignore

Ignoring Files with .gitignore

Git’s ability to track files is powerful, but sometimes you need to exclude certain files or directories from version control. This is typically done using a .gitignore file.

Why Ignore Files?

• Sensitive Information: Avoid accidentally sharing passwords, API keys, authentication tokens, or other sensitive data in your repository.
• System-Specific Files: Operating systems (e.g., macOS’s .DS_Store files) and applications (e.g., IDE configuration files) often create files that are not relevant to the project itself.
• Generated Files: Files automatically generated by build processes or other tools (e.g., node_modules in Node.js projects) should typically be ignored. These can be recreated easily.
• Local Notes: Keep personal notes or to-do lists separate from your main project.

Creating a .gitignore File

1. Create a file named .gitignore in the root directory of your project.
2. Add patterns to specify which files or directories to ignore.

Patterns in .gitignore:

• *.txt: Ignores all files ending with .txt.
• /folder/: Ignores the entire folder directory (note the trailing slash).
• folder/*: Ignores all files within the folder directory.
• !file.txt: Excludes file.txt from being ignored (used to override a more general rule).

Example .gitignore Content:

.DS_Store
/node_modules/
/vscode/
/notes/
authentication.js

Adding and Committing .gitignore:

After creating and editing .gitignore, add it to your repository and commit the changes:

git add .gitignore
git commit -m "Added .gitignore to ignore specific files"

Global .gitignore

For consistent ignoring across multiple projects, you can create a global .gitignore file. Git’s configuration allows you to specify a path to a global .gitignore file:

git config --global core.excludesfile ~/.gitignore_global

(This uses ~/.gitignore_global as the path for the global file; you can choose a different location.)

Cleaning the Git Cache

If you add a pattern to .gitignore after already tracking files matching the pattern, you might need to clear the Git cache:

git rm -r --cached .
git add .
git commit -m "Cleaned cache after updating .gitignore"

It’s best practice to create a .gitignore file early in your project’s lifecycle to prevent accidental tracking of unwanted files.