Preamble

This project aims to create a uniform interface to Openstack API clients.

Unfortunately, nova, keystone, and glance clients are very inconsistent. A lot of code is copied between all these clients instead of moving it to a common library. The code was edited without synchronization between clients, so, they have different behaviour:

• all client constructors use different parameters (api_key in nova or password in keystone and so on);
• keystoneclient authenticates immediately in __init__, while novaclient does in lazily during first method call;
• {keystone,nova}client can manage service catalogs and accept keystone's auth URI while glanceclient allows endpoints only;
• keystoneclient can support authorization with an unscoped token but novaclient doesn't;
• novaclient uses class composition while keystoneclient uses inheritance.

Quickstart

from openstackclient_base.base import monkey_patch
monkey_patch()
from openstackclient_base.client import HttpClient
http_client = HttpClient(username="...", password="...", tenant_name="...", auth_uri="...")

from openstackclient_base.nova.client import ComputeClient
print ComputeClient(http_client).servers.list()

from openstackclient_base.keystone.client import IdentityPublicClient
print IdentityPublicClient(http_client).tenants.list()

Architecture

The openstack-base library contains two main classes:

• HttpClient - an httplib2.Http descedant that manages authentication, endpoints, auth URI, service catalog, and API versioning;
• BaseClient - base class for actual clients (e.g. volume, compute, image); it uses an underlying HttpClient (class composition).

Several clients are implemented. They should be moved to actual packages (novaclient, keystoneclient etc.). Monkey patch is not necessary, but recommended. It switches different clients one common base library.

• ComputeClient, VolumeClient - compute and volume clients for nova;
• v1.ImageClient, v2.ImageClient - clients for glance;
• IdentityAdminClient, IdentityPublicClient - admin and public clients for keystone.

A sample class ClientSet can be used for convenience. It should be created only once (providing auth information) and then actual client are accessible as its properties.

from openstackclient_base.client_set import ClientSet
cs = ClientSet(username="...", password="...", tenant_name="...", auth_uri="...")

print cs.compute.servers.list()
print cs.identity_public.tenants.list()