The OpenStackClient plugin system is designed so that the plugin need only be properly installed for OSC to find and use it. It utilizes the setuptools entry points mechanism to advertise to OSC the plugin module and supported commands.
Plugins are discovered by enumerating the entry points found under openstack.cli.extension and initializing the specified client module.
[entry_points]
openstack.cli.extension =
oscplugin = oscplugin.client
The client module must define the following top-level variables:
The client module must implement the following interface functions:
OSC enumerates the plugin commands from the entry points in the usual manner defined for the API version:
openstack.oscplugin.v1 =
plugin_list = oscplugin.v1.plugin:ListPlugin
plugin_show = oscplugin.v1.plugin:ShowPlugin
Note that OSC defines the group name as openstack. so the version should not contain the leading ‘v’ character.
DEFAULT_OSCPLUGIN_API_VERSION = '1'
# Required by the OSC plugin interface
API_NAME = 'oscplugin'
API_VERSION_OPTION = 'os_oscplugin_api_version'
API_VERSIONS = {
'1': 'oscplugin.v1.client.Client',
}
# Required by the OSC plugin interface
def make_client(instance):
"""Returns a client to the ClientManager
Called to instantiate the requested client version. instance has
any available auth info that may be required to prepare the client.
:param ClientManager instance: The ClientManager that owns the new client
"""
plugin_client = utils.get_client_class(
API_NAME,
instance._api_version[API_NAME],
API_VERSIONS)
client = plugin_client()
return client
# Required by the OSC plugin interface
def build_option_parser(parser):
"""Hook to add global options
Called from openstackclient.shell.OpenStackShell.__init__()
after the builtin parser has been initialized. This is
where a plugin can add global options such as an API version setting.
:param argparse.ArgumentParser parser: The parser object that has been
initialized by OpenStackShell.
"""
parser.add_argument(
'--os-oscplugin-api-version',
metavar='<oscplugin-api-version>',
default=utils.env(
'OS_OSCPLUGIN_API_VERSION',
default=DEFAULT_OSCPLUGIN_API_VERSION),
help='OSC Plugin API version, default=' +
DEFAULT_OSCPLUGIN_API_VERSION +
' (Env: OS_OSCPLUGIN_API_VERSION)')
return parser