49 lines
1.9 KiB
Python
49 lines
1.9 KiB
Python
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"""
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This example demonstrates explicit setting of heartbeat and blocked connection
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timeouts.
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Starting with RabbitMQ 3.5.5, the broker's default hearbeat timeout decreased
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from 580 seconds to 60 seconds. As a result, applications that perform lengthy
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processing in the same thread that also runs their Pika connection may
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experience unexpected dropped connections due to heartbeat timeout. Here, we
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specify an explicit lower bound for heartbeat timeout.
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When RabbitMQ broker is running out of certain resources, such as memory and
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disk space, it may block connections that are performing resource-consuming
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operations, such as publishing messages. Once a connection is blocked, RabbiMQ
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stops reading from that connection's socket, so no commands from the client will
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get through to te broker on that connection until the broker unblocks it. A
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blocked connection may last for an indefinite period of time, stalling the
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connection and possibly resulting in a hang (e.g., in BlockingConnection) until
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the connection is unblocked. Blocked Connectin Timeout is intended to interrupt
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(i.e., drop) a connection that has been blocked longer than the given timeout
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value.
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"""
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import pika
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def main():
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# NOTE: These paramerers work with all Pika connection types
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params = pika.ConnectionParameters(heartbeat_interval=600,
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blocked_connection_timeout=300)
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conn = pika.BlockingConnection(params)
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chan = conn.channel()
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chan.basic_publish('', 'my-alphabet-queue', "abc")
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# If publish causes the connection to become blocked, then this conn.close()
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# would hang until the connection is unblocked, if ever. However, the
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# blocked_connection_timeout connection parameter would interrupt the wait,
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# resulting in ConnectionClosed exception from BlockingConnection (or the
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# on_connection_closed callback call in an asynchronous adapter)
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conn.close()
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if __name__ == '__main__':
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main()
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