Publisher-Subscriber

Enable an Publisher to announce events to multiple interested Subscribers asynchronously, without coupling the senders to the receivers. 

When to use this pattern?

• Broadcast information to multiple consumers.

• Send information to Subscribers without requiring real-time responses from the Subscribers. 

We can achieve the above pattern using Azure service bus Topic

Considerations  

• Use Existing technologies (Service Bus, Event Hubs, Event Grid)  

• Subscription Handling  

• Security  

• Subsets of messages (topics, content filtering)

• Wildcard Subscribers  

• Bi-directional Communications  - It's always one-directional, apply a request-reply pattern for bi-directional messages

• Message Ordering  - Order is not maintained

• Message priority  

• Poison Messages - Dead letter messages 

• Repeated Messages  

• Message Expiration  

• Message Scheduling