Service Clients Usage

Tests make requests against APIs using service clients. Service clients are specializations of the RestClient class. The service clients that cover the APIs exposed by a service should be grouped in a service clients module. A service clients module is python module where all service clients are defined. If major API versions are available, submodules should be defined, one for each version.

The ClientsFactory class helps initializing all clients of a specific service client module from a set of shared parameters.

The ServiceClients class provides a convenient way to get access to all available service clients initialized with a provided set of credentials.

The clients management module

class ClientsFactory(module_path, client_names, auth_provider, **kwargs)[source]

Builds service clients for a service client module

This class implements the logic of feeding service client parameters to service clients from a specific module. It allows setting the parameters once and obtaining new instances of the clients without the need of passing any parameter.

ClientsFactory can be used directly, or consumed via the ServiceClients class, which manages the authorization part.

class ServiceClients(credentials, identity_uri, region=None, scope=None, disable_ssl_certificate_validation=True, ca_certs=None, trace_requests='', client_parameters=None, proxy_url=None)[source]

Service client provider class

The ServiceClients object provides a useful means for tests to access service clients configured for a specified set of credentials. It hides some of the complexity from the authorization and configuration layers.


# johndoe is a tempest.lib.auth.Credentials type instance
johndoe_clients = clients.ServiceClients(johndoe, identity_uri)

# List servers in default region
johndoe_servers_client = johndoe_clients.compute.ServersClient()
johndoe_servers = johndoe_servers_client.list_servers()

# List servers in Region B
johndoe_servers_client_B = johndoe_clients.compute.ServersClient(
johndoe_servers = johndoe_servers_client_B.list_servers()

Set of service client modules available in Tempest and plugins

Set of stable service clients from Tempest and service clients exposed by plugins. This set of available modules can be used for automatic configuration.


PluginRegistrationException – if a plugin exposes a service_version already defined by Tempest or another plugin.


from tempest import config
params = {}
for service_version in available_modules():
    service = service_version.split('.')[0]
    params[service] = config.service_client_config(service)
service_clients = ServiceClients(creds, identity_uri,

Dict of service client modules available in Tempest.

Provides a dict of stable service modules available in Tempest, with service_version as key, and the module object as value.

Compute service client modules