I've noticed that some apps send incorrect messages to a certain queue in RabbitMQ. Since lots of apps can access RabbitMQ in my environment, it's too difficult to identify the producers by reviewing codes.
Is there any way to find the producers? Do I need some monitoring tools?
Not without modifying the clients.
The AMQP protocol provides the app-id property exactly for that purpose. Message publishers should set the app-id when publishing messages to RabbitMQ so that consumers can infer the source of the message.