Mono对象而不是Mono

Question

好吧，所以我有下面的方法，但我试图摆脱使用。块()，因此尝试实现Mono，但得到错误< code >所需的类型:List

原始代码

@GetMapping("/user/{userId}")
public List<CatalogItem> getUserMoviesRating(@PathVariable String userId) {

    UserRating ratings = webClientBuilder.build()
            .get()
            .uri("http://localhost:8083/ratingsdata/users/" + userId)
            .retrieve()
            .bodyToMono(UserRating.class)
            .block();

    assert ratings != null;
    return ratings.getUserRating().stream().map(rating -> {

        Movies movie = webClientBuilder.build()
                .get()
                .uri("http://localhost:8082/movies/"  + rating.getMovieId())
                .retrieve()
                .bodyToMono(Movies.class)
                .block();

        assert movie != null;
        return new CatalogItem(movie.getName(), movie.getDesc(), rating.getRating());
    }).collect(Collectors.toList());
}}

我尝试以非阻塞方式重构使用 Mono

@GetMapping("/user/{userId}")
public List <Mono<CatalogItem>> getUserMoviesRating(@PathVariable String userId) {

    Mono<UserRating> ratings = webClientBuilder.build()
            .get()
            .uri("http://localhost:8083/ratingsdata/users/" + userId)
            .retrieve()
            .bodyToMono(UserRating.class);

    return ratings.map(userRating -> userRating.getUserRating().stream().map(rating -> {
        Mono<Movies> movies = webClientBuilder.build()
                .get()
                .uri("http://localhost:8082/movies/" + rating.getMovieId())
                .retrieve()
                .bodyToMono(Movies.class);
        return movies.map(m -> new CatalogItem(m.getName(), m.getDesc(), rating.getRating()));
    }).collect(Collectors.toList()));
}

Answer 1

将 java 8 Stream API 与 Reactor 发布者相结合并不是最佳解决方案，因为这会使代码的可读性降低，并且它们的工作方式不同。你可以看看这里了解更多细节如果userRating.getUserRating（）返回一个评级列表，你可以试试这个代码。

  public Mono <List<CatalogItem>> getUserMoviesRating(@PathVariable String userId) {

    Mono<UserRating> ratings = webClientBuilder.build()
        .get()
        .uri("http://localhost:8083/ratingsdata/users/" + userId)
        .retrieve()
        .bodyToMono(UserRating.class);

    return ratings.flatMapMany(userRating -> Flux.fromIterable(userRating.getUserRating()))
        .flatMap(rating->this.getMovie(rating.getMovieId()))
        .map(m -> new CatalogItem(m.getName(), m.getDesc(), rating.getRating()))
        .collectList();
  }
    
  private Mono<Movies> getMovie(String movieId){
    return webClientBuilder.build()
        .get()
        .uri("http://localhost:8082/movies/" + movieId)
        .retrieve()
        .bodyToMono(Movies.class);
  }