How to Stop Git From Monitoring Changes in File Mode (chmod)

Managing File Permissions in Git

Working on a project frequently requires modifying file permissions to meet development requirements. To ensure you have the appropriate access during development, you may, for example, use chmod -R 777 on all files. However, these changes can become troublesome when Git begins tracking them, resulting in undesired updates to your repository.

Fortunately, Git can be configured to ignore file mode changes. This post will look at how you may use Git to monitor only the essential changes, keeping your repository tidy and focused on the actual code changes.

Using Scripts to Ignore File Mode Changes in Git.

The offered scripts handle the issue of Git tracking file mode changes, ensuring that only necessary changes are committed to the repository. The first script uses Git configuration command git config core.fileMode false. This command instructs Git to disregard file mode changes globally or for the current repository, so preventing undesirable permission changes from being tracked. This is especially useful in circumstances where file permissions need to be adjusted for development but must remain unchanged in the main repository.

The second script is a pre-commit hook written in shell. The shebang line #!/bin/sh specifies the shell interpreter. The command find . -type f -exec chmod 644 {} \; searches for all files in the current directory and subdirectories and sets their permissions to 644. This guarantees that the executable bits are removed before committing. The final command, git add -u, stages all updated files for the next commit while disregarding untracked files. This automatic procedure helps to maintain consistent file permissions in the repository without requiring manual intervention.

Automating Permission Management in Python

The third script uses Python to handle file permissions and stage changes in Git. The script imports the required modules os and subprocess. It defines the directory to clean up and traverses the directory tree with os.walk. Using os.chmod(file_path, 0o644), the permissions of each identified file are changed to 644. This guarantees that all files have the appropriate permissions before they are committed to the repository.

The last step of the Python script is to stage the changes in Git. The command subprocess.run(['git', 'add', '-u']) initiates a subprocess operation to prepare all updated files for the next commit. By automating the process of updating file permissions and staging changes, the script assists developers in keeping their repository clean and consistent, free of undesirable permission changes.

git config core.fileMode false

#!/bin/sh
# Remove executable bit before commit
find . -type f -exec chmod 644 {} \;
git add -u

import os
import subprocess

# Define the directory to clean up
dir_to_clean = '.'

# Traverse the directory tree
for root, dirs, files in os.walk(dir_to_clean):
    for name in files:
        file_path = os.path.join(root, name)
        # Remove the executable bit
        os.chmod(file_path, 0o644)

# Stage the changes in Git
subprocess.run(['git', 'add', '-u'])

Advanced techniques for managing file permissions in Git.

Another facet of managing file permissions in Git is the use of the .gitattributes file. This file can be added to your repository to regulate how Git handles certain file properties, including permissions. Defining particular attributes in the .gitattributes file ensures that specific files or folders maintain the correct permissions, regardless of local changes. For example, you could use patterns to match files and configure characteristics to prevent mode changes from being tracked.

To accomplish this, create or modify a .gitattributes file in your repository. You can add lines like * -diff to restrict Git from tracking changes in file modes across all files, or *.sh -diff to limit this setting to shell scripts. This method allows for more precise control over which files' mode changes are ignored, complementing the global git config core.fileMode false setting and providing a more targeted approach.