.juju_plugins.yaml

plugins_repos:
  - https://github.com/juju/plugins.git
  - https://github.com/bloodearnest/plugins.git#juju-local-dns
  - https://github.com/bloodearnest/plugins.git#juju-add-local-env

juju-pluginator.py

#!/usr/bin/env python

import errno
from hashlib import md5
from os import listdir, makedirs, path, symlink, unlink
import subprocess
import sys
import yaml

CONFIG_PATH = '~/.juju_plugins.yaml'
PLUGINS_DIR = '~/.juju_plugins'
CHECKOUTS_DIR = '~/.juju_plugins_checkouts'
PLUGINS_REPOS = ['https://github.com/juju/plugins.git']


def load_config(config_path=CONFIG_PATH):
    with file(path.expanduser(config_path)) as f:
        config = yaml.load(f)
    config.setdefault('plugins_repos', PLUGINS_REPOS)
    config.setdefault('plugins_dir', PLUGINS_DIR)
    config.setdefault('checkouts_dir', CHECKOUTS_DIR)
    return config


def pluginate(config):
    seen_commands = []

    for repo in config['plugins_repos']:
        parts = repo.split('#')
        if len(parts) > 1:
            repo = parts[0]
            branch = parts[1]
        else:
            branch = 'master'

        plugins_dir = path.expanduser(config['plugins_dir'])
        mkdir_p(plugins_dir, 0o744)
        checkouts_dir = path.expanduser(config['checkouts_dir'])
        mkdir_p(checkouts_dir, 0o774)

        repo_hash = md5()
        repo_hash.update('{}#{}'.format(repo, branch))
        co_path = path.join(checkouts_dir, repo_hash.hexdigest())

        if not path.exists(co_path):
            base_path = checkouts_dir
            cmds = ['git clone -b {} {} {}'.format(branch, repo,
                                                   repo_hash.hexdigest())]
        else:
            base_path = co_path
            cmds = ['git fetch --all',
                    'git reset --hard origin/{}'.format(branch)]

        for cmd in cmds:
            pipes = subprocess.Popen(cmd, cwd=base_path,
                                     stdout=sys.stdout,
                                     stderr=sys.stderr,
                                     shell=True)
            pipes.wait()

        new_commands = set(listdir(co_path)).difference(set(seen_commands))
        symlink_commands(co_path, new_commands, plugins_dir)
        map(lambda f: seen_commands.append(f), new_commands)

    print("\nDon't forget to add to your .bashrc:\n\nexport"
          " PATH=$PATH:{}".format(plugins_dir))


def symlink_commands(base, commands, plugins_dir):
    for f in commands:
        file_path = path.join(base, f)
        if '.' not in f and path.isfile(file_path):
            dest = path.join(plugins_dir, f)
            if path.exists(dest):
                unlink(dest)
            symlink(file_path, dest)


def mkdir_p(dir_path, perms):
    if not path.exists(dir_path):
        try:
            makedirs(dir_path, perms)
        except OSError as exc:
            if exc.errno == errno.EEXIST and path.isdir(dir_path):
                pass
            else:
                raise


if __name__ == '__main__':
    config_path = CONFIG_PATH
    if len(sys.argv) > 1:
        config_path = sys.argv[1]
    pluginate(load_config(config_path))