i have application which consumes topic from producer application using pulsar. i need a logic or some configuration to remove the messages from queue for a topic once it is consumed by my consumer application.Whenever my consumer application is restarted it gets all the messages in queue, even the previously received one

CodePudding user response：

You are most likley not sending an acknowledgement that you have consumed the message successfully:

Documentation states:

Pulsar is built on the publish-subscribe pattern (often abbreviated to pub-sub). In this pattern, producers publish messages to topics; consumers subscribe to those topics, process incoming messages, and send acknowledgements to the broker when processing is finished.

In order to acknowledge a message after consuming it, you do:

consumer.acknowledge(msg);

Reference: https://pulsar.apache.org/docs/concepts-messaging/#acknowledgement