git-me/git-me.py

#!/usr/bin/env python3

import os, argparse, sys, csv, subprocess


def eprint(*all):
    print(*all, file=sys.stderr)


STORAGE_LOC = os.environ['GIT_ME_STORE'] if 'GIT_ME_STORE' in os.environ else os.environ['HOME'] + '/.config/git-me'

eprint("git-me identity store: " + STORAGE_LOC)

STCOL_LEN = 3
STCOL_SLUG = 0
STCOL_NAME = 1
STCOL_EMAIL = 2


def add(args):
    slug = args.slug.lower()
    name = args.name
    email = args.email

    try:
        with open(STORAGE_LOC, 'r') as fstore:
            tsvin = csv.reader(fstore, delimiter='\t')

            for row in tsvin:
                if len(row) < STCOL_LEN:
                    continue
                if row[STCOL_SLUG].lower() == slug:
                    eprint("An identity with that slug already exists!")
                    eprint(f"    Slug: {row[STCOL_SLUG]}")
                    eprint(f"    Name: {row[STCOL_NAME]}")
                    eprint(f"  E-mail: {row[STCOL_EMAIL]}")
                    return False
    except FileNotFoundError:
        pass

    # now add it
    with open(STORAGE_LOC, 'a+') as fstore:
        fstore.write(f"\n{slug}\t{name}\t{email}\n")

    return True


def list_idents(args):
    print("# Slug\t\tName\t\tE-mail Address")
    with open(STORAGE_LOC, 'r') as fstore:
        tsvin = csv.reader(fstore, delimiter='\t')

        for row in tsvin:
            if len(row) < STCOL_LEN:
                continue
            print(f"{row[STCOL_SLUG]}\t\t{row[STCOL_NAME]}\t\t{row[STCOL_EMAIL]}")
    return True


def assert_hook(args):
    result_name = subprocess.run(['git', 'config', '--local', '--get', 'user.name'], stdout=subprocess.PIPE)
    so_name = result_name.stdout.decode().strip()
    result_email = subprocess.run(['git', 'config', '--local', '--get', 'user.email'], stdout=subprocess.PIPE)
    so_email = result_email.stdout.decode().strip()

    if result_email.returncode + result_name.returncode > 0:
        if result_name.returncode > 0:
            eprint("git-me: No user.name specified!")
        else:
            eprint(f"git-me: user.name OK = {so_name}")

        if result_email.returncode > 0:
            eprint("git-me: No user.email specified!")
        else:
            eprint(f"git-me: user.email OK = {so_email}")

        eprint("git-me: Either specify a config manually or use `git me use <id>`.")
        return False
    else:
        eprint(f"git-me: OK. (user.name = {so_name}, user.email = {so_email})")
        return True


def remove(args):
    slug = args.idslug
    os.rename(STORAGE_LOC, STORAGE_LOC + "~tmp")

    with open(STORAGE_LOC + "~tmp", 'r') as tsvin, open(STORAGE_LOC, 'w') as tsvout:
        tsvin = csv.reader(tsvin, delimiter='\t')
        tsvout = csv.writer(tsvout, delimiter='\t')

        for row in tsvin:
            if len(row) < STCOL_LEN:
                continue
            if row[STCOL_SLUG].lower() == slug:
                # delete; ignore
                pass
            else:
                tsvout.writerow(row)

        os.unlink(STORAGE_LOC + "~tmp")
    return True


def switch_identity(args):
    slug = args.idslug
    with open(STORAGE_LOC, 'r') as fstore:
        tsvin = csv.reader(fstore, delimiter='\t')

        for row in tsvin:
            if len(row) < STCOL_LEN:
                continue
            if row[STCOL_SLUG].lower() == slug:
                proc_name = subprocess.run(["git", "config", "--local", "user.name", row[STCOL_NAME]])
                if proc_name.returncode != 0:
                    eprint("git-me: Failed to set user.name! (non-zero exit code. Are you in a git repo?)")
                    return False
                else:
                    proc_email = subprocess.run(["git", "config", "--local", "user.email", row[STCOL_EMAIL]])
                    if proc_name.returncode != 0:
                        eprint("git-me: Failed to set user.email! (non-zero exit code.)")
                        return False
                return True
        else:
            eprint(f"git-me: Unable to find identity with {slug}")
            return False


if __name__ == "__main__":
    parser = argparse.ArgumentParser(
        description='Manages repository identities. Environment variable GIT_ME_STORE can be used to override location of identity store.',
    )

    subparser = parser.add_subparsers(help='sub-command help', dest='cmd')
    subparser.required = True

    parser_assert = subparser.add_parser('assert', aliases=['check', 'hook', 'ck'])
    parser_assert.set_defaults(func=assert_hook)

    parser_add = subparser.add_parser('add', aliases=['mk'])
    parser_add.add_argument('slug', type=str, help='A short, easy-to-type code to represent this id')
    parser_add.add_argument('name', type=str, help='Your display name')
    parser_add.add_argument('email', type=str, help='Your e-mail address')
    parser_add.set_defaults(func=add)

    parser_list = subparser.add_parser('list', aliases=['ls'])
    parser_list.set_defaults(func=list_idents)

    parser_remove = subparser.add_parser('remove', aliases=['rm'])
    parser_remove.add_argument('idslug', type=str, help='The slug of the identity to remove.')
    parser_remove.set_defaults(func=remove)

    parser_switch = subparser.add_parser('use', aliases=['switch', 'choose', 'enable'])
    parser_switch.add_argument('idslug', type=str, help='The slug of the identity to enable.')
    parser_switch.set_defaults(func=switch_identity)

    args = parser.parse_args(sys.argv[1:])
    if 'func' in args:
        if args.func(args):
            exit(0)
        else:
            exit(1)
    else:
        print("git-me: Please specify a command!", file=sys.stderr)
        exit(2)