- Use this if you want the response as fast as possible, immediately on the client
- Request and response model is not always ideal
- real time notification, when client wants real time notification from backend
- user just logged in/message is just received
- push model is better → it’s “forcing”, which can be good or bad
Push
- Steps
- Client connects to server
- Server sends data to client
- Client doesn’t have to request anything, the only thing it needs is the connection to server
- The protocol must be bidirectional
- Used by
RabbitMQ
- Message sent to the queue, and it pushes to the clients that are connected to it (consumers)
- Pros
- It’s real time. It’s called push because the result is pushed immediately as the moment the event is generated
- You’re literally writing to the client socket
- Cons
- client must be online
- client might not be able to handle (that’s why
kafka handles this differently than rabbitmq, it uses long polling).
- Server doesn’t have the knowledge whether the client can handle it or not
- Requires a bidirectional protocol
- Polling is preferred for light clients