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Using the BlockingChannel.consume generator to consume messages
===============================================================
.. _example_blocking_basic_get:
The :py:meth:`BlockingChannel.consume <pika.adapters.blocking_connection.BlockingChannel.consume>` method is a generator that will return a tuple of method, properties and body.
When you escape out of the loop, be sure to call consumer.cancel() to return any unprocessed messages.
Example of consuming messages and acknowledging them::
import pika
connection = pika.BlockingConnection()
channel = connection.channel()
# Get ten messages and break out
for method_frame, properties, body in channel.consume('test'):
# Display the message parts
print method_frame
print properties
print body
# Acknowledge the message
channel.basic_ack(method_frame.delivery_tag)
# Escape out of the loop after 10 messages
if method_frame.delivery_tag == 10:
break
# Cancel the consumer and return any pending messages
requeued_messages = channel.cancel()
print 'Requeued %i messages' % requeued_messages
# Close the channel and the connection
channel.close()
connection.close()
If you have pending messages in the test queue, your output should look something like::
(pika)gmr-0x02:pika gmr$ python blocking_nack.py
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=1', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=2', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=3', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=4', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=5', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=6', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=7', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=8', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=9', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
<Basic.Deliver(['consumer_tag=ctag1.0', 'redelivered=True', 'routing_key=test', 'delivery_tag=10', 'exchange=test'])>
<BasicProperties(['delivery_mode=1', 'content_type=text/plain'])>
Hello World!
Requeued 1894 messages
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