[rabbitmq-discuss] Design Decision

[Michael Klishin]

On 9 April 2014 at 18:03:44, Tobias Bühlmann (tbuehlmann.android at googlemail.com) wrote:
> > So, the problem: I have a relational database with a notifications  
> table where each notification has many associated apps. Each  
> app has itself many devices. Now, a producer will check the table  
> for new notifications with a specific state. If there are any,  
> grab them and produce a message for each device in each app associated  
> with the new notification. After that, some consumer workers  
> will work the queue(s) off and deliver the messages to the devices.  

Tobias,

Can you elaborate how apps and devices are named? Does the publisher
know much about them? This is a very important detail.

If I understand your scenario correctly, all devices across all apps
should get notifications of a specific kind. If so, you can make your consumers
declare server-named queues (their names won’t be known to the publisher)
and bind them to a topic exchange with a pattern like this:

notifications.[type]

As long as routing can happen on the type, the publisher won’t have to know
anything about consumers. This is largely the point of the exchange/queue separation
in the protocol. 
--  
MK  

Software Engineer, Pivotal/RabbitMQ