If you have not already done so, prepare the broker distribution before running the example.
To run the example, simply type mvn verify from this directory, or mvn -PnoServer verify if you want to start and create the server manually.
This example demonstrates Slow Consumer policy KILL and NOTIFY and the associated address-settings.
How often the broker checks for Slow Consumers is configurable by slow-consumer-check-period in the brokers address-settings. The default value is for slow-consumer-check-period is 5 seconds. A broker considers a consumer slow if the slow-consumer-threshold is not been met. The slow-consumer-threshold is the number of messages consumed by the consumer within a second. When a slow consumer is detected, the broker action depends on which slow-consumer-policy is configured.
The slow-consumer-policy KILL will kill the consumers connection
The slow-consumer-policy NOTIFY will send a CONSUMER_SLOW management notification that an application can receive
There are 2 example clients:
KillSlowConsumerExample sends messages to a queue “slow.consumer.kill”. It then starts a consumer BUT does not consume any messages. It waits for 8 seconds and tries to consume a message. It expects to receive an exception as the connection should already be closed.
NotifySlowConsumerExample sends messages to a queue “slow.consumer.notify”. It creates a consumer on the topic “notify.topic” that has been configured as the broker's management-notification-address. It then starts a consumer on “slow.consumer.notify” BUT does not consume any messages. The consumer on “notify.topic” will receive a CONSUMER_SLOW management notification and then stop the client.