class documentation

A transport implementation which buffers data in memory and keeps track of its other state without providing any behavior.

StringTransport has a number of attributes which are not part of any of the interfaces it claims to implement. These attributes are provided for testing purposes. Implementation code should not use any of these attributes; they are not provided by other transports.

Method __init__ Undocumented
Method abortConnection Abort the connection. Same as loseConnection, but also toggles the aborted instance variable to True.
Method clear Discard all data written to this transport so far.
Method getHost Similar to getPeer, but returns an address describing this side of the connection.
Method getPeer Get the remote address of this connection.
Method loseConnection Close the connection. Does nothing besides toggle the disconnecting instance variable to True.
Method pauseProducing Pause producing data.
Method registerProducer Register to receive data from a producer.
Method resumeProducing Resume producing data.
Method stopProducing Stop producing data.
Method unregisterProducer Stop consuming data from a producer, without disconnecting.
Method value Retrieve all data which has been buffered by this transport.
Method write Write some data to the physical connection, in sequence, in a non-blocking fashion.
Method writeSequence Write an iterable of byte strings to the physical connection.
Instance Variable connected Undocumented
Instance Variable disconnected A bool which is False until abortConnection is called, then True.
Instance Variable disconnecting A bool which is False until loseConnection is called, then True.
Instance Variable hostAddr None or an object which will be returned as the host address of this transport. If None, a nasty tuple will be returned instead.
Instance Variable io A io.BytesIO which holds the data which has been written to this transport since the last call to clear. Use value instead of accessing this directly.
Instance Variable peerAddr None or an object which will be returned as the peer address of this transport. If None, a nasty tuple will be returned instead.
Instance Variable producer If a producer is currently registered, producer is a reference to it. Otherwise, None.
Instance Variable producerState The state of this StringTransport in its capacity as an IPushProducer. One of 'producing', 'paused', or 'stopped'.
Instance Variable streaming If a producer is currently registered, streaming refers to the value of the second parameter passed to registerProducer.
Method _checkState Undocumented
Instance Variable _lenient By default StringTransport enforces that resumeProducing is not called after the connection is lost. This is to ensure that any code that does call resumeProducing after the connection is lost is not blindly expecting ...
def __init__(self, hostAddress=None, peerAddress=None, lenient=False): (source)

Undocumented

def abortConnection(self): (source)

Abort the connection. Same as loseConnection, but also toggles the aborted instance variable to True.

def clear(self): (source)

Discard all data written to this transport so far.

This is not a transport method. It is intended for tests. Do not use it in implementation code.

def getHost(self): (source)

Similar to getPeer, but returns an address describing this side of the connection.

Returns
An IAddress provider.
def getPeer(self): (source)

Get the remote address of this connection.

Treat this method with caution. It is the unfortunate result of the CGI and Jabber standards, but should not be considered reliable for the usual host of reasons; port forwarding, proxying, firewalls, IP masquerading, etc.

Returns
An IAddress provider.
def loseConnection(self): (source)

Close the connection. Does nothing besides toggle the disconnecting instance variable to True.

def pauseProducing(self): (source)

Pause producing data.

Tells a producer that it has produced too much data to process for the time being, and to stop until resumeProducing() is called.

def registerProducer(self, producer, streaming): (source)

Register to receive data from a producer.

This sets self to be a consumer for a producer. When this object runs out of data (as when a send(2) call on a socket succeeds in moving the last data from a userspace buffer into a kernelspace buffer), it will ask the producer to resumeProducing().

For IPullProducer providers, resumeProducing will be called once each time data is required.

For IPushProducer providers, pauseProducing will be called whenever the write buffer fills up and resumeProducing will only be called when it empties. The consumer will only call resumeProducing to balance a previous pauseProducing call; the producer is assumed to start in an un-paused state.

Parameters
producerUndocumented
streamingTrue if producer provides IPushProducer, False if producer provides IPullProducer.
Raises
RuntimeErrorIf a producer is already registered.
def resumeProducing(self): (source)

Resume producing data.

This tells a producer to re-add itself to the main loop and produce more data for its consumer.

def stopProducing(self): (source)

Stop producing data.

This tells a producer that its consumer has died, so it must stop producing data for good.

def unregisterProducer(self): (source)

Stop consuming data from a producer, without disconnecting.

def value(self): (source)

Retrieve all data which has been buffered by this transport.

This is not a transport method. It is intended for tests. Do not use it in implementation code.

Returns
bytesA bytes giving all data written to this transport since the last call to clear.
def write(self, data): (source)

Write some data to the physical connection, in sequence, in a non-blocking fashion.

If possible, make sure that it is all written. No data will ever be lost, although (obviously) the connection may be closed before it all gets through.

Parameters
dataThe data to write.
def writeSequence(self, data): (source)

Write an iterable of byte strings to the physical connection.

If possible, make sure that all of the data is written to the socket at once, without first copying it all into a single byte string.

Parameters
dataThe data to write.
disconnected: bool = (source)

A bool which is False until abortConnection is called, then True.

disconnecting: bool = (source)

A bool which is False until loseConnection is called, then True.

hostAddr = (source)

None or an object which will be returned as the host address of this transport. If None, a nasty tuple will be returned instead.

A io.BytesIO which holds the data which has been written to this transport since the last call to clear. Use value instead of accessing this directly.

peerAddr = (source)

None or an object which will be returned as the peer address of this transport. If None, a nasty tuple will be returned instead.

producer = (source)

If a producer is currently registered, producer is a reference to it. Otherwise, None.

producerState: str = (source)

The state of this StringTransport in its capacity as an IPushProducer. One of 'producing', 'paused', or 'stopped'.

streaming = (source)

If a producer is currently registered, streaming refers to the value of the second parameter passed to registerProducer.

def _checkState(self): (source)

Undocumented

_lenient = (source)

By default StringTransport enforces that resumeProducing is not called after the connection is lost. This is to ensure that any code that does call resumeProducing after the connection is lost is not blindly expecting resumeProducing to have any impact.

However, if your test case is calling resumeProducing after connection close on purpose, and you know it won't block expecting further data to show up, this flag may safely be set to True.

Defaults to False.