Git commit client hook

README.md

Git commit client hook

Provides Git hook enforcing commit message.

• first line length must be less than 50 characters.
• if applicable, second line may be empty.
• length of every lines may be less than 72 characters.

Installation instructions

Setup hook for all repositories

Install git 2.9 or higher. Run the commands below:

cd /path/to/all/your/gists
git clone git@gist.github.com:0bf6ef017e1e738b344e.git
git config --global core.hooksPath $PWD

Setup hook in a specific repository

In terminal:

1. Go to a Git repository root:

cd /path/to/my/git/repository

1. Run the following command:

curl -s https://gist.githubusercontent.com/tristan0x/0bf6ef017e1e738b344e/raw/d71a6a0eb2cbebe2842fda86259593824110dda6/setup-commit-msg-hook | sh -e -

Example

$ git init /tmp/foo
$ cd /tmp/foo
$ curl -s https://gist.githubusercontent.com/tristan0x/0bf6ef017e1e738b344e/raw/d71a6a0eb2cbebe2842fda86259593824110dda6/setup-commit-msg-hook | sh -e -
# adding git/hooks/commit-msg
# adding git/hooks/validate-commit.py
$

Hint for effectiveness

You can add an alias in your shell configuration file:

alias git-setup-cogniteev-hook='curl -s https://gist.githubusercontent.com/tristan0x/0bf6ef017e1e738b344e/raw/d71a6a0eb2cbebe2842fda86259593824110dda6/setup-commit-msg-hook | sh -e -'

Resources

• Customizing Git - An Example Git-Enforced Policy
• A Note About Git Commit Messages
• Good Commit Messages And Enforcing Them With Git Hooks

commit-msg

#!/bin/sh

DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
exec < /dev/tty
"$DIR/validate-commit.py" $1

setup-commit-msg-hook

#!/bin/sh -e

gist_user=tristan0x
gist_id=0bf6ef017e1e738b344e
revision="8da1eb6e8deb6ae15963178945136e1b1c82c9ba"
gist_root="https://gist.githubusercontent.com/$gist_user/$gist_id/raw"

has_error=no
if ! [ -d .git/hooks ] ; then
  echo "Error: cannot find directory .git/hooks" >&2
  has_error=true
fi

for f in commit-msg validate-commit.py ; do
  if [ -f ".git/hooks/$f" ] ; then
    echo "Error: .git/hooks/$f already exists." >&2
    has_error=true
  fi
done
if [ "x$has_error" = xtrue ] ;then
  echo "Abort." >&2
  exit 1
fi

for f in commit-msg validate-commit.py ; do
  echo "# adding git/hooks/$f"
  curl -s "$gist_root/$revision/$f" > ".git/hooks/$f"
  chmod +x ".git/hooks/$f"
done

validate-commit.py

#!/usr/bin/python

import sys
import os
from subprocess import call

editor = os.environ.get('EDITOR', 'vim')

message_file = sys.argv[1]


def check_format_rules(lineno, line):
    real_lineno = lineno + 1
    if lineno == 0:
        if len(line) > 50:
            return 'Error %d: First line should be less than 50 characters ' \
                'in length.' % (real_lineno,)
    if lineno == 1:
        if line:
            return 'Error %d: Second line should be empty.' % (real_lineno,)
    if len(line) > 72:
        return 'Error %d: No line should be over 72 characters long.' % (
            real_lineno,)
    return False


while True:
    commit_msg = list()
    errors = list()
    with open(message_file) as commit_fd:
        lineno = 0
        for line in commit_fd:
            is_comment = line.startswith('#')
            stripped_line = line.strip()
            commit_msg.append(line)
            if is_comment:
                continue
            e = check_format_rules(lineno, stripped_line)
            if e:
                errors.append(e)
            lineno += 1
    if errors:
        with open(message_file, 'a') as commit_fd:
            commit_fd.write('#\n# GIT COMMIT MESSAGE FORMAT ERRORS:\n')
            for error in errors:
                commit_fd.write('#    %s\n' % (error,))
        re_edit = raw_input(
            'Invalid git commit message format. '
            'Press y to edit and n to cancel the commit. [y/n] ')
        if re_edit.lower() in ('n', 'no'):
            sys.exit(1)
        call('%s %s' % (editor, message_file), shell=True)
        continue
    break