Use OpenAI to generate git commits

README.md

A python script that when run will look at the files committed to git staging and uses a openai api key from the zsh environment and write a commit summary, and use that to commit the changes.

Uses uv to make this a standalone script.

Written using Claude.

I use this to automatically generate git commits to my blog source code.

git_commit_ai.py

#!/usr/bin/env -S uv run
# /// script
# requires-python = ">=3.10"
# dependencies = [
#     "openai",
# ]
# ///
"""
AI-powered Git Commit Script
Generates commit messages using OpenAI API based on staged changes
"""

import os
import subprocess
import sys
from openai import OpenAI


def run_git_command(args):
    """Run a git command and return the output."""
    try:
        result = subprocess.run(
            ["git"] + args,
            capture_output=True,
            text=True,
            check=True
        )
        return result.stdout.strip()
    except subprocess.CalledProcessError as e:
        print(f"Error running git command: {e.stderr}")
        sys.exit(1)


def get_staged_diff():
    """Get the diff of staged changes."""
    diff = run_git_command(["diff", "--cached"])
    if not diff:
        print("No staged changes found. Please stage your changes first with 'git add'.")
        sys.exit(1)
    return diff


def get_staged_files():
    """Get list of staged files."""
    files = run_git_command(["diff", "--cached", "--name-only"])
    return files.split('\n') if files else []


def generate_commit_message(diff, files):
    """Generate commit message using OpenAI API."""
    api_key = os.environ.get("OPENAI_API_KEY")
    
    if not api_key:
        print("Error: OPENAI_API_KEY not found in environment variables.")
        print("Please set it in your ~/.zshrc or export it in your current session:")
        print("  export OPENAI_API_KEY='your-api-key-here'")
        sys.exit(1)
    
    client = OpenAI(api_key=api_key)
    
    # Prepare the prompt
    files_list = "\n".join(files)
    prompt = f"""Based on the following git diff, generate a concise and descriptive commit message.

The commit message should:
- Start with a conventional commit type (feat, fix, docs, style, refactor, test, chore)
- Be clear and specific about what changed
- Be under 72 characters for the first line
- Optionally include a blank line and more details if the change is complex

Files changed:
{files_list}

Git diff:
{diff[:4000]}

Generate only the commit message, nothing else."""

    try:
        response = client.chat.completions.create(
            model="gpt-4o-mini",
            messages=[
                {"role": "system", "content": "You are a helpful assistant that writes clear, concise git commit messages following conventional commit standards."},
                {"role": "user", "content": prompt}
            ],
            temperature=0.7,
            max_tokens=200
        )
        
        commit_message = response.choices[0].message.content.strip()
        # Remove surrounding quotes if present
        commit_message = commit_message.strip('"\'')
        return commit_message
        
    except Exception as e:
        print(f"Error calling OpenAI API: {e}")
        sys.exit(1)


def commit_changes(message):
    """Commit the staged changes with the generated message."""
    try:
        subprocess.run(
            ["git", "commit", "-m", message],
            check=True
        )
        print("\n✓ Changes committed successfully!")
        print(f"\nCommit message:\n{message}")
    except subprocess.CalledProcessError as e:
        print(f"Error committing changes: {e}")
        sys.exit(1)


def main():
    print("Checking staged changes...")
    
    # Get staged files and diff
    staged_files = get_staged_files()
    staged_diff = get_staged_diff()
    
    print(f"\nStaged files ({len(staged_files)}):")
    for file in staged_files:
        print(f"  - {file}")
    
    print("\nGenerating commit message using OpenAI...")
    commit_message = generate_commit_message(staged_diff, staged_files)
    
    print(f"\nProposed commit message:")
    print("-" * 60)
    print(commit_message)
    print("-" * 60)
    
    # Ask for confirmation
    response = input("\nProceed with this commit message? (y/n): ").lower().strip()
    
    if response == 'y':
        commit_changes(commit_message)
    else:
        print("\nCommit cancelled.")
        sys.exit(0)


if __name__ == "__main__":
    main()