Spring WebFlux WebClient - 如何解决 400 错误请求

Posted 2023-02-26

【中文标题】Spring WebFlux WebClient - 如何解决 400 错误请求

【英文标题】：Spring WebFlux WebClient - How to resolve 400 Bad Request

【发布时间】：2020-09-02 10:32:42

【问题描述】：

我是响应式编程的新手，我正在使用 Spring WebFlux 的 WebClient 向以下 URL 发出 POST 请求，作为我的 Spring Boot 应用程序的一部分，以将现有测验分配给候选人。我无法理解我在构建 WebClient 请求时做错了什么。

终点

https://www.flexiquiz.com/api/v1/users/user_id/quizzes

在我的请求正文中，我需要传递从另一个 API 获得的测验 ID（工作正常）。

   "quiz_id": ""

除了传递请求正文之外，我还将 X-API-KEY 作为请求标头的一部分传递。

但是，当我尝试到达终点时，我收到 "message":"400: Bad Request" 错误。

下面是我的代码。

QuizRequest.java

@JsonInclude(JsonInclude.Include.NON_NULL)
@Data
public class QuizRequest 

  @JsonProperty("quiz_id")
  @NotBlank
  private String quizId;

  public QuizRequest(@NotBlank String quizId) 
    this.quizId = quizId;
  

FlexiQuizClient.java

@Service
@Slf4j
public class FlexiQuizClient 

  private static final String USER_AGENT = "WebClient for FlexiQuiz";

  private final WebClient webClient;

  @Value("$flexiquiz.baseurl")
  private String FLEXIQUIZ_API_BASE_URL;

  @Value("$flexiquiz.key")
  private String FLEXIQUIZ_API_KEY;

  @Autowired
  public FlexiQuizClient() 
    this.webClient = WebClient.builder()
        .baseUrl(FLEXIQUIZ_API_BASE_URL)
        .defaultHeader(HttpHeaders.USER_AGENT, USER_AGENT)
        .filter(logRequest())
        .build();
  

  public String assignQuizToCandidate(String userId, QuizRequest quizRequest) 
    return Objects.requireNonNull(webClient.post()
        .uri(FLEXIQUIZ_API_BASE_URL + "/v1/users/" + userId + "/quizzes")
        .header("X-API-KEY", FLEXIQUIZ_API_KEY)
        .body(Mono.just(quizRequest), QuizRequest.class)
        .exchange()
        .block())
        .bodyToMono(String.class)
        .block();
  

  private ExchangeFilterFunction logRequest() 
    return (clientRequest, next) -> 
      log.info("Request:  ", clientRequest.method(), clientRequest.url());
      clientRequest.headers()
          .forEach((name, values) -> values.forEach(value -> log.info("=", name, value)));
      return next.exchange(clientRequest);
    ;
  

在我的资源类（控制器）中，我正在调用 Web 客户端方法，如下所示：

ResponseResource.java

private String assignQuizToCandidate(String userId, QuizRequest quizRequest)
      throws ParseException 
    log.info("Assigning a quiz based on your skill");
    String message = quizClient.assignQuizToCandidate(userId, quizRequest);
    log.info("message from status: " + message);
    JSONParser parser = new JSONParser();
    JSONObject json = (JSONObject) parser.parse(message);
    return (String) json.get("message");

在另一个方法中，我调用了上面的方法，如下所示。

QuizRequest quizRequest = new QuizRequest(openQuiz.get().getQuizId());
String status = assignQuizToCandidate(userId, quizRequest);

以下是日志：

2020-05-17 10:20:09.938 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] Channel acquired, now 1 active connections and 0 inactive connections
2020-05-17 10:20:09.938 DEBUG 32600 --- [ctor-http-nio-1] r.netty.http.client.HttpClientConnect    : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] Handler is being applied: uri=https://www.flexiquiz.com/api/v1/users/userid/quizzes, method=POST
2020-05-17 10:20:09.939 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] onStateChange(POSTuri=/api/v1/users/userid/quizzes, connection=PooledConnectionchannel=[id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443], [request_prepared])
2020-05-17 10:20:09.939 DEBUG 32600 --- [ctor-http-nio-1] o.s.http.codec.json.Jackson2JsonEncoder  : [1bbedd72] Encoding [QuizRequest(quizId=quizid)]
2020-05-17 10:20:09.941 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] onStateChange(POSTuri=/api/v1/users/userid/quizzes, connection=PooledConnectionchannel=[id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443], [request_sent])
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] r.n.http.client.HttpClientOperations     : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] Received response (auto-read:false) : [Cache-Control=private, Content-Type=text/html; charset=utf-8, Server=Microsoft-IIS/10.0, Date=Sun, 17 May 2020 04:50:10 GMT, Content-Length=30]
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] onStateChange(POSTuri=/api/v1/users/userid/quizzes, connection=PooledConnectionchannel=[id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443], [response_received])
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] o.s.w.r.f.client.ExchangeFunctions       : [1bbedd72] Response 400 BAD_REQUEST
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] r.n.http.client.HttpClientOperations     : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] Received last HTTP packet
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] onStateChange(POSTuri=/api/v1/users/userid/quizzes, connection=PooledConnectionchannel=[id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443], [response_completed])
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] onStateChange(POSTuri=/api/v1/users/userid/quizzes, connection=PooledConnectionchannel=[id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443], [disconnecting])
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] Releasing channel
2020-05-17 10:20:10.189 DEBUG 32600 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] Channel cleaned, now 0 active connections and 1 inactive connections
2020-05-17 10:20:10.190 DEBUG 32600 --- [ctor-http-nio-1] reactor.netty.channel.FluxReceive        : [id: 0x2b404095, L:/192.168.0.106:62197 - R:www.flexiquiz.com/208.117.41.204:443] Subscribing inbound receiver [pending: 1, cancelled:false, inboundDone: true]
2020-05-17 10:20:10.190 DEBUG 32600 --- [ctor-http-nio-1] o.s.core.codec.StringDecoder             : [1bbedd72] Decoded ""message":"400: Bad Request""
2020-05-17 10:20:10.190  INFO 32600 --- [nio-8086-exec-6] i.d.ivrauto.resource.ResponseResource    : message from status: "message":"400: Bad Request"
2020-05-17 10:20:10.190  INFO 32600 --- [nio-8086-exec-6] i.d.ivrauto.resource.ResponseResource    : json.get(message): 400: Bad Request
2020-05-17 10:20:10.190  INFO 32600 --- [nio-8086-exec-6] o.h.e.i.AbstractFlushingEventListener    : Processing flush-time cascades
2020-05-17 10:20:10.195 DEBUG 32600 --- [nio-8086-exec-6] o.h.e.i.AbstractFlushingEventListener    : Dirty checking collections

以下是我尝试访问的终点。

POST: /v1/users/user_id/quizzes

请求示例

$ curl https://www.flexiquiz.com/api/v1/users/06e3244f-1381-4da4-aa75-996981b42edb/quizzes 
-H "X-API-KEY: fcb5f59c-2a2f-44a9-8261-33cbfa97be99"
-d quiz_id="1153af46-9580-4672-af78-f23ce2577a14"

示例响应

                             
    "message": "200: OK"

【问题讨论】：

您能否尝试在不使用自定义用户代理标头的情况下发送请求。

@ThomasAndolf 不，它没有帮助。仍然收到 400 Bad Request。

您能否发布您的日志或在调试中运行您的应用程序，以便我们查看实际发出的请求

@ThomasAndolf 用日志编辑了我的问题。

您的服务器端点是什么样的？您提供了客户端代码，但没有提供服务器方法。

【参考方案1】：

基于@ThomasAndolf 的回答是我必须做的。

public String assignQuizToCandidate(String userId, String quizId) 
    final MultiValueMap<String, String> data = new LinkedMultiValueMap<>();
    data.add("quiz_id", quizId);

    return webClient.post()
        .uri(FLEXIQUIZ_API_BASE_URL + "/v1/users/" + userId + "/quizzes")
        .header("X-API-KEY", FLEXIQUIZ_API_KEY)
        .bodyValue(data)
        .retrieve()
        .bodyToMono(String.class)
        .block();
  

我将输出作为字符串，因为响应仅包含带有以下消息的字符串： "message": "200: OK"

【参考方案2】：

您的问题可能是您以错误的格式发送数据。您在正文中以application/json 格式发布数据。

但是，如果您查看请求，它是使用 curl 中的 -d 标志发出的。

来自 curl 文档：

-d,--数据

(HTTP) 将 POST 请求中的指定数据发送到 HTTP 服务器，方式与 当用户填写 HTML 表单并按下提交按钮时，浏览器会执行此操作。这会导致 curl 使用内容类型 application/x-www-form-urlencoded 将数据传递给服务器。 与 -F、--form 比较。

这基本上意味着您需要以FORM格式发送数据。

Webflux 文档说明如何将数据作为表单请求发送。

Webflux Send FormData

所以你的代码应该看起来像（有点）：

public QuizResponse assignQuizToCandidate(String userId, String quizId) 

    final MultiValueMap<String, String> formData = new LinkedMultiValueMap<>();
    formData.add("quiz_id", quizId);

    return webClient.post()
        .uri(FLEXIQUIZ_API_BASE_URL + "/v1/users/" + userId + "/quizzes")
        .header("X-API-KEY", FLEXIQUIZ_API_KEY)
        .bodyValue(formData)
        .retrive()
        .bodyToMono(QuizResponse.class)
        .block();

【讨论】：

你是绝对正确的人！我会接受你的回答。另外，我会根据您的回答添加我的解决方案。