MsgEffectwhen compared to their predecessor in form of
HttpEffectis much more powerful tool, taking the possibilities to the next level. Once you're inside your Effect, use any Observable patterns you desire as long as any output from the final, returned stream, is an Event.
matchEventoperator that is just an abstraction over RxJS
filteroperator, with additional functionalities and type-safety underneath.
exhaustMapor other flattening operator. The snippet below shows the example error handling strategy for fetching an author.
actoperator that reduces the required boilerplate to minimum applying the error handling underneath the operator.
GET_USER_RESULTevent without replying to producer. As mentioned in previous chapter, event interface defines two additional metadata attributes:
correlationId. Typically when dealing with RPC (request-response) messaging, the event handler (effect) has to reply in case of success or error. In order to do that, effect has to combine the mapped outgoing event with incoming event metadata, passing the information about the correlation id that the producer will look for and the reply channel where the outgoing event should be routed to.
replyfunction that makes the mapping more explicit.