Reactor Mono/Flux - 根据条件遍历数组和 return 结果

Question

这个问题看起来很基础，但我只是想学习响应式编程，无法找出最佳答案。

我有以下同步代码，它只是遍历提供者并找到第一个用户：

public interface PrincipalProvider {
    public User findUser(String name);
}

public class PrincipalProviderComposite implements PrincipalProvider {
    private final List<PrincipalProvider> providers;

    @Override
    public User findUser(String name) {
        User user = null;
        for(PrincipalProvider provider: providers) {
            user = provider.findUser(name);
            if(user != null)
                break;
        }
        return user;
    }
}

现在我需要使此代码异步，提供者可能 return 用户或可能 return Mono.empty().

public interface PrincipalProvider {
    public Mono<User> findUser(String name);
}

Answer 1

public Mono<User> findUser(String name) {
    return Flux.fromIterable(providers)
               .concatMap(provider -> provider.findUser(name))
               .next();
}

Reactor Mono/Flux - 根据条件遍历数组和 return 结果

Reactor Mono/Flux - iterating over array and return result by condition

java

reactive-programming

project-reactor