class documentation

class twisted.application.internet.ClientService(service.Service): (source)

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A ClientService maintains a single outgoing connection to a client endpoint, reconnecting after a configurable timeout when a connection fails, either before or after connecting.

Present Since16.1.0
Method __init__
Method whenConnected Retrieve the currently-connected Protocol, or the next one to connect.
Method startService Start this ClientService, initiating the connection retry loop.
Method stopService Stop attempting to reconnect and close any existing connections.
Class Variable _log Undocumented
Instance Variable _machine Undocumented

Inherited from Service:

Instance Variable running A boolean which indicates whether the service is running.
Instance Variable name A str which is the name of the service or None.
Instance Variable parent An IServiceCollection which is the parent or None.
Method __getstate__ Undocumented
Method setName Set the name of the service.
Method setServiceParent Set the parent of the service. This method is responsible for setting the parent attribute on this service (the child service).
Method disownServiceParent Use this API to remove an IService from an IServiceCollection.
Method privilegedStartService Do preparation work for starting the service.
_log = (source)


def __init__(self, endpoint, factory, retryPolicy=None, clock=None, prepareConnection=None): (source)
ParametersendpointA stream client endpoint provider which will be used to connect when the service starts.
factoryA protocol factory which will be used to create clients for the endpoint.
retryPolicyA policy configuring how long ClientService will wait between attempts to connect to endpoint. (type: callable taking (the number of failed connection attempts made in a row (int)) and returning the number of seconds to wait before making another attempt.)
clockThe clock used to schedule reconnection. It's mainly useful to be parametrized in tests. If the factory is serialized, this attribute will not be serialized, and the default value (the reactor) will be restored when deserialized. (type: IReactorTime)
prepareConnectionA single argument callable that may return a Deferred. It will be called once with the protocol each time a new connection is made. It may call methods on the protocol to prepare it for use (e.g. authenticate) or validate it (check its health).

The prepareConnection callable may raise an exception or return a Deferred which fails to reject the connection. A rejected connection is not used to fire an Deferred returned by whenConnected. Instead, ClientService handles the failure and continues as if the connection attempt were a failure (incrementing the counter passed to retryPolicy).

Deferreds returned by whenConnected will not fire until any Deferred returned by the prepareConnection callable fire. Otherwise its successful return value is consumed, but ignored.

Present Since Twisted 18.7.0

(type: callable)
_machine = (source)


def whenConnected(self, failAfterFailures=None): (source)

Retrieve the currently-connected Protocol, or the next one to connect.

ParametersfailAfterFailuresnumber of connection failures after which the Deferred will deliver a Failure (None means the Deferred will only fail if/when the service is stopped). Set this to 1 to make the very first connection failure signal an error. Use 2 to allow one failure but signal an error if the subsequent retry then fails. (type: int or None)
Returnsa Deferred that fires with a protocol produced by the factory passed to __init__ (type: Deferred that may:)
def startService(self): (source)

Start this ClientService, initiating the connection retry loop.

def stopService(self): (source)

Stop attempting to reconnect and close any existing connections.

Returnsa Deferred that fires when all outstanding connections are closed and all in-progress connection attempts halted.
API Documentation for Twisted, generated by pydoctor 20.12.1 at 2021-02-28 19:53:36.