Solace REST messaging uses bi-directional HTTP POST requests to exchange messages in both directions as shown in the following figure. This enables REST clients to send messages to and receive messages from any Solace PubSub+ message broker clients.
REST producers send message contents in the body of an HTTP POST request. For request/reply scenarios, the response contents are carried in the body of the HTTP 200 OK responses. For REST consumers, the message broker sends the message in the body of an HTTP POST request. And again for request/reply scenarios, the response contents are carried in the HTTP 200 OK responses. This is explained in more detail in the REST Messaging Protocol section.
The use of HTTP POST requests in both directions. It removes the possibility of message loss which can exist when using HTTP GET requests to poll for messages. It also enables much higher performance and overall message rate when multiple, parallel HTTP connections are used.