如何使用Spring data-mongodb-reactive从受限制的集合中流式传输

Question

I'm trying to use this interesting repository method :

@Tailable
Flux<Movie> findWithTailableCursorBy();

by expose it in a controller, to stream new saved docs in a capped collection:

This is a DataAppInitializr :

@EventListener(ApplicationReadyEvent.class)
public void run(ApplicationReadyEvent evt) {

      operations.collectionExists(Movie.class)
                  .flatMap(exists -> exists ? operations.dropCollection(Movie.class) : Mono.just(exists))
                  .then(operations.createCollection(Movie.class, CollectionOptions.empty()
                             .size(256 * 256)
                             .maxDocuments(10)
                             .capped()))
                  .thenMany(operations.insertAll(Flux.just("Jeyda", "Kaf Efrit").map(title-> new Movie(title)).collectList()))
                  .subscribe();
}

This is the controller method :

@GetMapping(value = "/tail", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
Flux<Movie> allTail() {
    return movieRepository.findWithTailableCursorBy();
}

I got no exception, I'm just getting a white page in the browser and no stream of new docs. Am I missing a step ?

Thank you in advance!

Answer 1

There are two aspects in your question that do not fit what you want to achieve:

1. Your code contains blocking bits: block() . Do not call .block() in initializers and event handlers during startup or when receiving events triggered by reactive infrastructure. Blocking is the easiest way to disrupt any functionality and makes your application defunct.
2. Browsers aren't the ideal tool to consume streams with a page view. Rather use cURL .

Besides that, you seem to have a mismatch between Flux<Person> and Flux<Movie> .

Answer 2

The issue comes from SecurityWebFilterChain from the spring-security-webflux. I should contact concerned people to notify them. Thank you for your support!