Known subclasses: twisted.internet.abstract.FileDescriptor, twisted.internet.iocpreactor.abstract.FileHandle

IConsumer implementations can mix this in to get registerProducer and unregisterProducer methods which take care of keeping track of a producer's state.

Subclasses must provide three attributes which _ConsumerMixin will read but not write:

  • connected: A bool which is True as long as the consumer has someplace to send bytes (for example, a TCP connection), and then False when it no longer does.
  • disconnecting: A bool which is False until something like ITransport.loseConnection is called, indicating that the send buffer should be flushed and the connection lost afterwards. Afterwards, True.
  • disconnected: A bool which is False until the consumer no longer has a place to send bytes, then True.

Subclasses must also override the startWriting method.

Instance Variable producer None if no producer is registered, otherwise the registered producer.
Instance Variable producerPaused A flag indicating whether the producer is currently paused. (type: bool)
Instance Variable streamingProducer 0 A flag indicating whether the producer was registered as a streaming (ie push) producer or not (ie a pull producer). This will determine whether the consumer may ever need to pause and resume it, or if it can merely call resumeProducing on it when buffer space is available.
Instance Variable streamingProducer bool or int
Method startWriting No summary
Method registerProducer Register to receive data from a producer.
Method unregisterProducer Stop consuming data from a producer, without disconnecting.
producer =
None if no producer is registered, otherwise the registered producer.
producerPaused =
A flag indicating whether the producer is currently paused. (type: bool)
streamingProducer 0 =
A flag indicating whether the producer was registered as a streaming (ie push) producer or not (ie a pull producer). This will determine whether the consumer may ever need to pause and resume it, or if it can merely call resumeProducing on it when buffer space is available.
streamingProducer =
bool or int
def startWriting(self):

Override in a subclass to cause the reactor to monitor this selectable for write events. This will be called once in unregisterProducer if loseConnection has previously been called, so that the connection can actually close.

def registerProducer(self, producer, streaming):

Register to receive data from a producer.

This sets this selectable to be a consumer for a producer. When this selectable runs out of data on a write() call, it will ask the producer to resumeProducing(). When the FileDescriptor's internal data buffer is filled, it will ask the producer to pauseProducing(). If the connection is lost, FileDescriptor calls producer's stopProducing() method.

If streaming is true, the producer should provide the IPushProducer interface. Otherwise, it is assumed that producer provides the IPullProducer interface. In this case, the producer won't be asked to pauseProducing(), but it has to be careful to write() data only when its resumeProducing() method is called.

def unregisterProducer(self):

Stop consuming data from a producer, without disconnecting.

API Documentation for twisted, generated by pydoctor at 2020-03-25 17:34:30.