Pull image for containers in the docker-compose file, service_names is a
    python list, if omitted pull all images

    path
        Path where the docker-compose file is stored on the server
    service_names
        If specified will pull only the image for the specified services

    CLI Example:

    .. code-block:: bash

        salt myminion dockercompose.pull /path/where/docker-compose/stored
        salt myminion dockercompose.pull /path/where/docker-compose/stored '[janus]'

def pull(path, service_names=None):
    '''
    Pull image for containers in the docker-compose file, service_names is a
    python list, if omitted pull all images

    path
        Path where the docker-compose file is stored on the server
    service_names
        If specified will pull only the image for the specified services

    CLI Example:

    .. code-block:: bash

        salt myminion dockercompose.pull /path/where/docker-compose/stored
        salt myminion dockercompose.pull /path/where/docker-compose/stored '[janus]'
    '''

    project = __load_project(path)
    if isinstance(project, dict):
        return project
    else:
        try:
            project.pull(service_names)
        except Exception as inst:
            return __handle_except(inst)
    return __standardize_result(True, 'Pulling containers images via docker-compose succeeded',
                                None, None)