# 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 a 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 to initialize 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)

  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)

  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.

  Examples:

      # 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(
          region='B')
      johndoe_servers = johndoe_servers_client_B.list_servers()

available_modules()

  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.

  Raises:

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

  Examples:

      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,
                                       client_parameters=params)

tempest_modules()

  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

- Compute Client Usage
  - `ServersClient`

this page last updated: 2026-06-02 11:22:24

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