Select Connection Adapter¶
Asynchronous adapter without third-party dependencies.
Interacting with Pika from another thread¶
pika.SelectConnection
’s I/O loop providesadd_callback_threadsafe()
to allow interacting with Pika from another thread.
Class Reference¶
A connection adapter that tries to use the best polling method for the platform pika is running on.
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class
pika.adapters.select_connection.
SelectConnection
(parameters=None, on_open_callback=None, on_open_error_callback=None, on_close_callback=None, custom_ioloop=None, internal_connection_workflow=True)[source]¶ An asynchronous connection adapter that attempts to use the fastest event loop adapter for the given platform.
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add_on_close_callback
(callback)¶ Add a callback notification when the connection has closed. The callback will be passed the connection and an exception instance. The exception will either be an instance of exceptions.ConnectionClosed if a fully-open connection was closed by user or broker or exception of another type that describes the cause of connection closure/failure.
Parameters: callback (callable) – Callback to call on close, having the signature: callback(pika.connection.Connection, exception)
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add_on_connection_blocked_callback
(callback)¶ RabbitMQ AMQP extension - Add a callback to be notified when the connection gets blocked (Connection.Blocked received from RabbitMQ) due to the broker running low on resources (memory or disk). In this state RabbitMQ suspends processing incoming data until the connection is unblocked, so it’s a good idea for publishers receiving this notification to suspend publishing until the connection becomes unblocked.
See also Connection.add_on_connection_unblocked_callback()
See also ConnectionParameters.blocked_connection_timeout.
Parameters: callback (callable) – Callback to call on Connection.Blocked, having the signature callback(connection, pika.frame.Method), where the method frame’s method member is of type pika.spec.Connection.Blocked
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add_on_connection_unblocked_callback
(callback)¶ RabbitMQ AMQP extension - Add a callback to be notified when the connection gets unblocked (Connection.Unblocked frame is received from RabbitMQ) letting publishers know it’s ok to start publishing again.
Parameters: callback (callable) – Callback to call on Connection.Unblocked, having the signature callback(connection, pika.frame.Method), where the method frame’s method member is of type pika.spec.Connection.Unblocked
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add_on_open_callback
(callback)¶ Add a callback notification when the connection has opened. The callback will be passed the connection instance as its only arg.
Parameters: callback (callable) – Callback to call when open
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add_on_open_error_callback
(callback, remove_default=True)¶ Add a callback notification when the connection can not be opened.
The callback method should accept the connection instance that could not connect, and either a string or an exception as its second arg.
Parameters: - callback (callable) – Callback to call when can’t connect, having the signature _(Connection, Exception)
- remove_default (bool) – Remove default exception raising callback
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channel
(channel_number=None, on_open_callback=None)¶ Create a new channel with the next available channel number or pass in a channel number to use. Must be non-zero if you would like to specify but it is recommended that you let Pika manage the channel numbers.
Parameters: - channel_number (int) – The channel number to use, defaults to the next available.
- on_open_callback (callable) – The callback when the channel is opened. The callback will be invoked with the Channel instance as its only argument.
Return type:
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close
(reply_code=200, reply_text='Normal shutdown')¶ Disconnect from RabbitMQ. If there are any open channels, it will attempt to close them prior to fully disconnecting. Channels which have active consumers will attempt to send a Basic.Cancel to RabbitMQ to cleanly stop the delivery of messages prior to closing the channel.
Parameters: Raises: pika.exceptions.ConnectionWrongStateError – if connection is closed or closing.
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consumer_cancel_notify
¶ Specifies if the server supports consumer cancel notification on the active connection.
Return type: bool
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classmethod
create_connection
(connection_configs, on_done, custom_ioloop=None, workflow=None)[source]¶ Implement :py:classmethod::pika.adapters.BaseConnection.create_connection().
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exchange_exchange_bindings
¶ Specifies if the active connection supports exchange to exchange bindings.
Return type: bool
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ioloop
¶ Returns: the native I/O loop instance underlying async services selected by user or the default selected by the specialized connection adapter (e.g., Twisted reactor, asyncio.SelectorEventLoop, select_connection.IOLoop, etc.) Return type: object
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is_closed
¶ Returns a boolean reporting the current connection state.
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is_closing
¶ Returns True if connection is in the process of closing due to client-initiated close request, but closing is not yet complete.
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is_open
¶ Returns a boolean reporting the current connection state.
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publisher_confirms
¶ Specifies if the active connection can use publisher confirmations.
Return type: bool
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update_secret
(new_secret, reason, callback=None)¶ RabbitMQ AMQP extension - This method updates the secret used to authenticate this connection. It is used when secrets have an expiration date and need to be renewed, like OAuth 2 tokens. Pass a callback to be notified of the response from the server.
Parameters: - new_secret (string) – The new secret
- reason (string) – The reason for the secret update
- callback (callable) – Callback to call on Connection.UpdateSecretOk, having the signature callback(pika.frame.Method), where the method frame’s method member is of type pika.spec.Connection.UpdateSecretOk
Raises: pika.exceptions.ConnectionWrongStateError – if connection is not open.
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