Wrapping git operations in Python

Personal notes. To see how Git works in Python, use the ** subprocess ** module ** Popen **.


class GitError(BaseException): pass


def git(cmd, *args):
     command = ("git", cmd) + args
     proc = Popen(command, stdin=-1,stdout=-1,stderr=-1)
     out, err = proc.communicate()

    if len(err) == 0:
        return out.strip()
    else:
        raise GitError(err.strip())

Let's create a class called ** GitUtility ** that applies this.

from subprocess import Popen

class GitError(BaseException):
    """
    This Error raises when git command runner has error.
    """

    pass

class GitUtility(object):
    """
    The GitUtility contains utility functions for operate git.
    """

    def __init__(self):

        return

    def run(self, cmd, *args):
        """
        This command is git command runner by subprocess.
        Return output or raise GitError if runner has error.
        """

        if isinstance(args[0], tuple):
            # Avoid duplicate tuple
            # ex. self.rev_parse("--show-toplevel")
            #   ->('git', 'rev-parse', ('--show-toplevel',))
            command = ("git", cmd) + tuple([arg for arg in args[0]])
        else:
            command = ("git", cmd) + args

        proc = Popen(command, stdin=-1,stdout=-1,stderr=-1)

        out, err = proc.communicate()

        if len(err) == 0:
            return out.strip()

        else:
            raise GitError(err.strip())

    def add(self, path):
        """
        Run git add command
        """

        self.run("add", path)

    def commit(self, commit_msg):
        """
        Run git commit
        """

        return self.run("commit", "-m", commit_msg)

    def rev_parse(self, *args):
        """
        Run git rev-parse command
        """
        return self.run("rev-parse", args)

    def get_toplevel(self):
        """
        Return git top level path using git rev-parse
        """

        return self.rev_parse("--show-toplevel")

For example, you can want to commit automatically, or you can get the repository path using rev-parse. If you apply it more, you can parse the log or get the contents of the file at the time of a certain commit.