This document is for Kombu's development version, which can be significantly different from previous releases. Get the stable docs here: 4.5.
Virtual Transport Base Class - kombu.transport.virtual
¶
Transports¶
-
class
kombu.transport.virtual.
Transport
(client, **kwargs)[source]¶ Virtual transport.
- Parameters
client (kombu.Connection) – The client this is a transport for.
-
Channel
= <class 'kombu.transport.virtual.base.Channel'>¶
-
Cycle
= <class 'kombu.utils.scheduling.FairCycle'>¶
-
polling_interval
= 1.0¶ Time to sleep between unsuccessful polls.
-
default_port
= None¶ port number used when no port is specified.
-
state
= <kombu.transport.virtual.base.BrokerState object>¶ Global
BrokerState
containing declared exchanges and bindings.
Channel¶
-
class
kombu.transport.virtual.
AbstractChannel
[source]¶ Abstract channel interface.
This is an abstract class defining the channel methods you’d usually want to implement in a virtual channel.
Note
Do not subclass directly, but rather inherit from
Channel
.
-
class
kombu.transport.virtual.
Channel
(connection, **kwargs)[source]¶ Virtual channel.
- Parameters
connection (ConnectionT) – The transport instance this channel is part of.
-
Message
= <class 'kombu.transport.virtual.base.Message'>¶ message class used.
-
state
¶ Broker state containing exchanges and bindings.
-
do_restore
= True¶ flag to restore unacked messages when channel goes out of scope.
-
exchange_types
= {'direct': <class 'kombu.transport.virtual.exchange.DirectExchange'>, 'fanout': <class 'kombu.transport.virtual.exchange.FanoutExchange'>, 'topic': <class 'kombu.transport.virtual.exchange.TopicExchange'>}¶ mapping of exchange types and corresponding classes.
-
exchange_declare
(exchange=None, type='direct', durable=False, auto_delete=False, arguments=None, nowait=False, passive=False)[source]¶ Declare exchange.
-
exchange_delete
(exchange, if_unused=False, nowait=False)[source]¶ Delete exchange and all its bindings.
-
queue_bind
(queue, exchange=None, routing_key='', arguments=None, **kwargs)[source]¶ Bind queue to exchange with routing key.
-
basic_qos
(prefetch_size=0, prefetch_count=0, apply_global=False)[source]¶ Change QoS settings for this channel.
Note
Only prefetch_count is supported.
-
prepare_message
(body, priority=None, content_type=None, content_encoding=None, headers=None, properties=None)[source]¶ Prepare message data.
-
flow
(active=True)[source]¶ Enable/disable message flow.
- Raises
NotImplementedError – as flow is not implemented by the base virtual implementation.
Message¶
-
class
kombu.transport.virtual.
Message
(payload, channel=None, **kwargs)[source]¶ Message object.
-
exception
MessageStateError
¶ The message has already been acknowledged.
-
args
¶
-
with_traceback
()¶ Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.
-
-
accept
¶
-
ack
(multiple=False)[source]¶ Acknowledge this message as being processed.
This will remove the message from the queue.
- Raises
MessageStateError – If the message has already been acknowledged/requeued/rejected.
-
property
acknowledged
¶ Set to true if the message has been acknowledged.
-
body
¶
-
channel
¶
-
content_encoding
¶
-
content_type
¶
-
decode
()[source]¶ Deserialize the message body.
Returning the original python structure sent by the publisher.
Note
The return value is memoized, use _decode to force re-evaluation.
-
delivery_info
¶
-
delivery_tag
¶
-
errors
= None¶
-
headers
¶
-
property
payload
¶ The decoded message body.
-
properties
¶
-
reject
(requeue=False)[source]¶ Reject this message.
The message will be discarded by the server.
- Raises
MessageStateError – If the message has already been acknowledged/requeued/rejected.
-
requeue
()[source]¶ Reject this message and put it back on the queue.
Warning
You must not use this method as a means of selecting messages to process.
- Raises
MessageStateError – If the message has already been acknowledged/requeued/rejected.
-
exception
Quality Of Service¶
-
class
kombu.transport.virtual.
QoS
(channel, prefetch_count=0)[source]¶ Quality of Service guarantees.
Only supports prefetch_count at this point.
- Parameters
channel (ChannelT) – Connection channel.
prefetch_count (int) – Initial prefetch count (defaults to 0).
-
can_consume
()[source]¶ Return true if the channel can be consumed from.
Used to ensure the client adhers to currently active prefetch limits.
-
can_consume_max_estimate
()[source]¶ Return the maximum number of messages allowed to be returned.
Returns an estimated number of messages that a consumer may be allowed to consume at once from the broker. This is used for services where bulk ‘get message’ calls are preferred to many individual ‘get message’ calls - like SQS.
- Returns
greater than zero.
- Return type
-
prefetch_count
= 0¶ current prefetch count value
-
restore_at_shutdown
= True¶ If disabled, unacked messages won’t be restored at shutdown.
In-memory State¶
-
class
kombu.transport.virtual.
BrokerState
(exchanges=None)[source]¶ Broker state holds exchanges, queues and bindings.
-
bindings
= None¶ This is the actual bindings registry, used to store bindings and to test ‘in’ relationships in constant time. It has the following structure:
{ (queue, exchange, routing_key): arguments, # ..., }
-
exchanges
= None¶ Mapping of exchange name to
kombu.transport.virtual.exchange.ExchangeType
-
queue_index
= None¶ The queue index is used to access directly (constant time) all the bindings of a certain queue. It has the following structure:
{ queue: { (queue, exchange, routing_key), # ..., }, # ..., }
-