A Python script to monitor Git commits and execute a specified command upon detecting changes.

on_git_commit_change.py

#!/usr/bin/env python3

# TL;DR- Put it in PATH and `chmod +x` and enjoy `on_git_commit_change.py -c -- command to run every time I make new commit`

# https://gist.github.com/gwpl/6f2c8f2574db6df770c51795d02cd458

import argparse
import subprocess
import time
import sys

def parse_arguments():
    parser = argparse.ArgumentParser(description="Monitor Git commit changes and execute a command.")
    parser.add_argument('-f', '--frequency', type=float, default=0.5, help='Frequency of checking for new commits in seconds.')
    parser.add_argument('-s', '--silent', action='store_true', help='Run in silent mode.')
    parser.add_argument('command', nargs=argparse.REMAINDER, help='Command to execute on new commit.')
    parser.add_argument('-a', '--after-change', action='store_true', help='Execute command only after observing a change.')
    parser.add_argument('-c', '--clear', action='store_true', help='Clear the terminal before logging new commit.')
    return parser.parse_args()

def log_info(message, silent):
    if not silent:
        print(f"INFO: {message}", file=sys.stderr)

def get_current_commit():
    return subprocess.check_output(['git', 'rev-parse', 'HEAD']).strip().decode('utf-8')

def main():
    args = parse_arguments()
    if not args.command:
        print("No command provided to execute on commit change.", file=sys.stderr)
        sys.exit(1)

    current_commit = None
    if args.after_change:
        # If the after-change flag is set, initialize current_commit to the current HEAD
        current_commit = get_current_commit()
        log_info(f"Current commit: {current_commit}", args.silent)

    while True:
        new_commit = get_current_commit()
        if new_commit != current_commit:
            if args.clear:
                subprocess.run(['clear'])
            log_info(f"New commit detected: {new_commit}", args.silent)
            # Run the git log command to show the latest commit details
            subprocess.run(['git', 'log', '-1', '--pretty=oneline'])
            current_commit = new_commit
            subprocess.run(args.command[1:])
        time.sleep(args.frequency)

if __name__ == "__main__":
    main()

x_README.md

TL;DR- Put it in PATH and chmod +x and enjoy on_git_commit_change.py -c -- command to run every time I make new commit

This script is a Python utility designed to monitor changes in a Git repository and execute a specified command whenever a new commit is detected. Here's a brief breakdown of its functionality:

• Argument Parsing: The script uses the argparse library to handle command-line arguments. These include:

  • -f or --frequency: Sets the time (in seconds) between each check for new commits.
  • -s or --silent: If specified, suppresses logging output.
  • -a or --after-change: Runs the command only after a change is detected, by initialising the current commit.
  • -c or --clear: Clears the terminal before logging information about a new commit.
  • command: The command to be executed when a new commit is detected.

• Commit Monitoring: It continuously monitors the latest commit in the current Git repository using the git rev-parse HEAD command to get the latest commit hash.

• Logging: It logs information to the stderr unless the silent mode is activated.

• Execution Trigger: Upon detecting a new commit (i.e., a change in the commit hash), it conditionally clears the terminal, logs the new commit, and executes the specified command.

• Loop: The script runs indefinitely, checking for new commits at intervals specified by the frequency argument.