volumes.py 文件源码

def get_config():
    '''Gather and sanity-check volume configuration data'''
    volume_config = {}
    config = hookenv.config()

    errors = False

    if config.get('volume-ephemeral') in (True, 'True', 'true', 'Yes', 'yes'):
        volume_config['ephemeral'] = True
    else:
        volume_config['ephemeral'] = False

    try:
        volume_map = yaml.safe_load(config.get('volume-map', '{}'))
    except yaml.YAMLError as e:
        hookenv.log("Error parsing YAML volume-map: {}".format(e),
                    hookenv.ERROR)
        errors = True
    if volume_map is None:
        # probably an empty string
        volume_map = {}
    elif not isinstance(volume_map, dict):
        hookenv.log("Volume-map should be a dictionary, not {}".format(
            type(volume_map)))
        errors = True

    volume_config['device'] = volume_map.get(os.environ['JUJU_UNIT_NAME'])
    if volume_config['device'] and volume_config['ephemeral']:
        # asked for ephemeral storage but also defined a volume ID
        hookenv.log('A volume is defined for this unit, but ephemeral '
                    'storage was requested', hookenv.ERROR)
        errors = True
    elif not volume_config['device'] and not volume_config['ephemeral']:
        # asked for permanent storage but did not define volume ID
        hookenv.log('Ephemeral storage was requested, but there is no volume '
                    'defined for this unit.', hookenv.ERROR)
        errors = True

    unit_mount_name = hookenv.local_unit().replace('/', '-')
    volume_config['mountpoint'] = os.path.join(MOUNT_BASE, unit_mount_name)

    if errors:
        return None
    return volume_config