Spring Reactive WebClient

Question

我有一个被动rest api（webflux），也使用spring WebClient类来请求来自其他休息服务的数据。

简化设计：

@PostMapping(value = "/document") 
public Mono<Document> save(@RequestBody Mono<Document> document){ 

//1st Problem: I do not know how to get the documentoOwner ID 
//that is inside the Document class from the request body without using .block() 
    Mono<DocumentOwner> documentOwner = documentOwnerWebClient() 
     .get().uri("/document-owner/{id}", document.getDocumentOwner().getId()) 
     .accept(MediaType.APPLICATION_STREAM_JSON) 
     .exchange() 
     .flatMap(do -> do.bodyToMono(DocumentOwner.class)); 

    //2nd Problem: I need to check (validate) if the documentOwner object is "active", for instance 
    //documentOwner and document instances below should be the object per se, not the Mono returned from the external API 
    if (!documentOwner.isActive) throw SomeBusinessException(); 

    document.setDocumentOwner(documentOwner); 

    //Now I can save the document in some reactive repository, 
    //and return the one saved with the given ID. 
    return documentRepository.save(document) 

} 

换句话说：我明白了（几乎）所有的单独的反应的例子，但我不能把它一起，构建一个简单的用例（获得 - >验证 - >保存 - >返回），而不会阻塞对象。

---

越接近我能得到的是：

@PostMapping(value = "/document") 
    public Mono<Document> salvar(@RequestBody Mono<Document> documentRequest){ 

     return documentRequest 
       .transform(this::getDocumentOwner) 
       .transform(this::validateDocumentOwner) 
       .and(documentRequest, this::setDocumentOwner) 
       .transform(this::saveDocument); 
    } 

附配的方法是：

private Mono<DocumentOwner> getDocumentOwner(Mono<Document> document) { 
     return document.flatMap(p -> documentOwnerConsumer.getDocumentOwner(p.getDocumentOwnerId())); 
    } 

    private Mono<DocumentOwner> validateDocumentOwner(Mono<DocumentOwner> documentOwner) { 

     return documentOwner.flatMap(do -> { 
      if (do.getActive()) { 
       return Mono.error(new BusinessException("Document Owner is Inactive")); 
      } 
      return Mono.just(do); 
     }); 


    } 

    private DocumentOwnersetDocumentOwner(DocumentOwner documentOwner, Document document) { 
     document.setDocumentOwner(documentOwner); 
     return document; 
    } 

    private Mono<Document> saveDocument(Mono<Document> documentMono) { 
     return documentMono.flatMap(documentRepository::save); 
    } 

我使用了Netty，SpringBoot，春WebFlux和无功蒙戈库。但有一些问题：

1）我收到错误： java.lang.IllegalStateException：只有一个连接接收订阅者允许。也许是因为我正在使用相同的documentRequest来转换和setDocumentOwner。我真的不知道。

2）setDocumentOwner方法没有被调用。所以要保存的文档对象不会更新。我相信可以有更好的方法来实现这个setDocumentOwner（）。

谢谢

Answer 1

我真的不明白这个问题的验证方面。 但它看起来像你试图组合反应型。这是反应堆与操作员完美结合的事情。

当然，还有更好的方法来处理程序的情况下，但在Mono API makes me think about this快速搜索：

Mono<Document> document = ... 
Mono<DocumentOwner> docOwner = ... 
another = Mono.when(document, docOwner) 
       .map(tuple -> { 
         Document doc = tuple.getT1(); 
         DocumentOwner owner = tuple.getT2(); 
         if(owner.getActive()) { 
          return Mono.error(new BusinessException("Document Owner is Inactive")); 
         } 
         doc.setDocumentOwner(owner); 
         return doc; 
       }) 
       .flatMap(documentRepository::save);