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deb-python-cassandra-driver/docs/api/cassandra/protocol.rst
Mark Florisson 02be9f441a Add some API documentation for Cython-based deserializers
2015-08-11 21:30:32 +01:00

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cassandra.protocol - Protocol Features

cassandra.protocol

Custom Payloads

Native protocol version 4+ allows for a custom payload to be sent between clients and custom query handlers. The payload is specified as a string:binary_type dict holding custom key/value pairs.

By default these are ignored by the server. They can be useful for servers implementing a custom QueryHandler.

See .Session.execute, :.Session.execute_async, .ResponseFuture.custom_payload.

ProtocolHandler

message_types_by_opcode

encode_message

decode_message

Faster Deserialization

When python-driver is compiled with Cython, it uses a Cython-based deserialization path to deserialize messages. There are two additional ProtocolHandler classes that can be used to deserialize response messages: the first is LazyProtocolHandler and the second is NumpyProtocolHandler.They can be used as follows:

from cassandra.protocol import NumpyProtocolHandler, LazyProtocolHandler
s.client_protocol_handler = LazyProtocolHandler   # for a result iterator
s.client_protocol_handler = NumpyProtocolHandler  # for a dict of NumPy arrays as result