kafka-python consumer not receiving messages

问题

I am having trouble with KafaConsumer to make it read from the beginning, or from any other explicit offset.

Running the command line tools for the consumer for the same topic , I do see messages with the --from-beginning option and it hangs otherwise

$ ./kafka-console-consumer.sh --zookeeper {localhost:port} --topic {topic_name} --from-beginning

If I run it through python, it hangs, which I suspect to be caused by incorrect consumer configs

consumer = KafkaConsumer(topic_name,
                     bootstrap_servers=['localhost:9092'],
                     group_id=None,
                     auto_commit_enable=False,
                     auto_offset_reset='smallest')

print "Consuming messages from the given topic"
for message in consumer:
    print "Message", message
    if message is not None:
        print message.offset, message.value

print "Quit"

Output:

Consuming messages from the given topic (hangs after that)

I am using kafka-python 0.9.5 and the broker runs kafka 8.2. Not sure what the exact problem is.

Set _group_id=None_ as suggested by dpkp to emulate the behavior of console consumer.

回答1:

The difference between the console-consumer and the python consumer code you have posted is the python consumer uses a consumer group to save offsets: group_id="test-consumer-group" . If instead you set group_id=None, you should see the same behavior as the console consumer.