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.Password(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).
For more information on this keystoneauth API, see Using Sessions.
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: 1GB server>,
<Flavor: 2GB server>,
<Flavor: 4GB server>,
<Flavor: 8GB server>,
<Flavor: 15.5GB 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.