Question regarding Reactor 3

[petivagyok16]

I know this is kind of irrelevant here, but i don't know any other channel to ask Reactor 3 questions. If you know a place i can ask my question feel free to share :)

So, i'd like to refactor my code, which consists of 3 Publishers (ReactiveMongoRepository responses), and i need all the responses from the repository in the same context to make calculations on them. Other difficulty is that 1 of the publisher is not the same type as the others (2 Mono, 1 Mono). How can i compose these publishers into one single stream in a form that i can access all the three values?

One more thing: does it make any sense to use .publishOn(Schedulers.parallel()) at all the three repository requests?

It looks like this:

return this.userRepository.findById(raterUserId)
	.publishOn(Schedulers.parallel())
	.flatMap(raterUser -> Mono.just(raterUser)
	.then(
		this.messageRepository.findById(messageId)
		.publishOn(Schedulers.parallel())
	        .single()
		.doOnError(this::messageNotFound)
		.flatMap(ratedMessage -> this.userRepository.findById(ratedMessage.getUserId())
								.publishOn(Schedulers.parallel())
								.flatMap(messageOwner -> { ... }

[petivagyok16]

I refactored the code above to:

return Flux.zip(
		this.messageRepository.findById(messageId),
		this.userRepository.findById(raterUserId),
		this.userRepository.findUserByMessage(messageId))
	.single()
	.doOnError(this::handleDatabaseError)
	.publishOn(Schedulers.parallel())
	.flatMap(publisherList -> this.rateMessage(rating, prevRating, raterUserId, messageId, publisherList))
	.then(Mono.just(ResponseEntity.ok().build()));

What do you think? .publishOn does any make sense there? Does it runs the zip() and repository processes on another thread?