Sending events
Event-driven structures are based on the fire-and-forget principle. Instead of sending data and waiting until the other part returns a response, it just sends data and continues executing.
This makes it different from the request-response architecture that we saw in the previous chapter. A request-response process will wait until an appropriate response is generated. Meanwhile, the execution of more code will stop, as the new data produced by the external system is required to continue.
In an event-driven system, there's no response data, at least not in the same sense. Instead, an event containing the request will be sent, and the task will just continue. Some minimal information could be returned to ensure that the event can be tracked later.
Event-driven systems can be implemented with request-response servers. This doesn't make them a pure request-response system. For example, a RESTful API that creates an event and returns an event...