python-novaclient/doc/source/user/python-api.rst

The novaclient Python API

novaclient

novaclient

Usage

First create a client instance with your credentials:

>>> from novaclient import client
>>> nova = client.Client(VERSION, USERNAME, PASSWORD, PROJECT_ID, AUTH_URL)

Here VERSION can be a string or novaclient.api_versions.APIVersion obj. If you prefer string value, you can use 1.1 (deprecated now), 2 or 2.X (where X is a microversion).

Alternatively, you can create a client instance using the keystoneauth session API:

>>> from keystoneauth1 import loading
>>> from keystoneauth1 import session
>>> from novaclient import client
>>> loader = loading.get_plugin_loader('password')
>>> auth = loader.load_from_options(auth_url=AUTH_URL,
...                                 username=USERNAME,
...                                 password=PASSWORD,
...                                 project_id=PROJECT_ID)
>>> sess = session.Session(auth=auth)
>>> nova = client.Client(VERSION, session=sess)

If you have PROJECT_NAME instead of a PROJECT_ID, use the project_name parameter. Similarly, if your cloud uses keystone v3 and you have a DOMAIN_NAME or DOMAIN_ID, provide it as user_domain_(name|id) and if you are using a PROJECT_NAME also provide the domain information as project_domain_(name|id).

novaclient adds 'python-novaclient' and its version to the user-agent string that keystoneauth produces. If you are creating an application using novaclient and want to register a name and version in the user-agent string, pass those to the Session:

>>> sess = session.Session(
...     auth=auth, app_name'nodepool', app_version'1.2.3')

If you are making a library that consumes novaclient but is not an end-user application, you can append a (name, version) tuple to the session's additional_user_agent property:

>>> sess = session.Session(auth=auth)
>>> sess.additional_user_agent.append(('shade', '1.2.3'))

For more information on this keystoneauth API, see Using Sessions <using-sessions.html>.

It is also possible to use an instance as a context manager in which case there will be a session kept alive for the duration of the with statement:

>>> from novaclient import client
>>> with client.Client(VERSION, USERNAME, PASSWORD,
...                    PROJECT_ID, AUTH_URL) as nova:
...     nova.servers.list()
...     nova.flavors.list()
...

It is also possible to have a permanent (process-long) connection pool, by passing a connection_pool=True:

>>> from novaclient import client
>>> nova = client.Client(VERSION, USERNAME, PASSWORD, PROJECT_ID,
...                      AUTH_URL, connection_pool=True)

Then call methods on its managers:

>>> nova.servers.list()
[<Server: buildslave-ubuntu-9.10>]

>>> nova.flavors.list()
[<Flavor: 256 server>,
 <Flavor: 512 server>,
 <Flavor: 1GiB server>,
 <Flavor: 2GiB server>,
 <Flavor: 4GiB server>,
 <Flavor: 8GiB server>,
 <Flavor: 15.5GiB server>]

>>> fl = nova.flavors.find(ram=512)
>>> nova.servers.create("my-server", flavor=fl)
<Server: my-server>

Warning

Direct initialization of novaclient.v2.client.Client object can cause you to "shoot yourself in the foot". See launchpad bug-report 1493576 for more details.

Reference

See the module reference </reference/index>.