spring boot没有看到请求参数

Question

我的角度应用程序正在调用Spring引导运行的REST API Web服务。以下是来自firefox Web控制台的参数转储：

我的春季启动webapp正在抛出此异常：

org.springframework.web.bind.MissingServletRequestParameterException: Required String parameter 'payload' is not present
    at org.springframework.web.method.annotation.RequestParamMethodArgumentResolver.handleMissingValue(RequestParamMethodArgumentResolver.java:198) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.method.annotation.AbstractNamedValueMethodArgumentResolver.resolveArgument(AbstractNamedValueMethodArgumentResolver.java:109) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:121) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:158) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:128) [spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) [javax.servlet-api-3.1.0.jar:3.1.0]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) [spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) [javax.servlet-api-3.1.0.jar:3.1.0]
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:841) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1650) [jetty-servlet-9.4.7.v20170914.jar:9.4.7.v20170914]
    at org.eclipse.jetty.websocket.server.WebSocketUpgradeFilter.doFilter(WebSocketUpgradeFilter.java:206) [websocket-server-9.4.7.v20170914.jar:9.4.7.v20170914]

这是我的方法......

@RequestMapping(value = "/login", method = RequestMethod.POST)
@ResponseBody
public String login(@RequestParam(NetworkKeyNames.KEY_PAYLOAD) String payload) throws IOException {
    log.error("Payload=" + payload);
    TypeReference<Map<String, String>> typeRef = new TypeReference<Map<String, String>>() {
    };
    Map<String, String> payloadMap = objectMapper.readValue(payload, typeRef);
    String username = payloadMap.get(NetworkKeyNames.KEY_USERNAME);
    String password = payloadMap.get(NetworkKeyNames.KEY_PASSWORD);

    String result = securityService.login(username, password);
    return result;
}

很明显，它正在击中我的春季启动应用程序，但参数发生了什么？有什么方法可以获得更多信息吗？

Answer 1

试试这个，我不确定你的Spring Boot版本，你可能需要调整一下。

    // Somewhere in package /service/dto
class PayloadDTO {
 String payload;

 public setPayload(String payload) {
  this.payload = payload;
 }

 public getPayload() {
  return payload;
 }
}

// Resource method
@PostMapping("/login")
public String login(@RequestBody PayloadDTO payload) throws IOException {
 log.error("Payload=" + payload.getPayload());
 TypeReference < Map < String, String >> typeRef = new TypeReference < Map < String, String >> () {};
 Map < String, String > payloadMap = objectMapper.readValue(payload.getPayload(), typeRef);
 String username = payloadMap.get(NetworkKeyNames.KEY_USERNAME);
 String password = payloadMap.get(NetworkKeyNames.KEY_PASSWORD);

 String result = securityService.login(username, password);
 return result;
}

Answer 2

我跑了一个卷发，卷曲打到了我的网络服务，所以我回到我的Angular应用程序，看看它为什么不把这些数据作为帖子发送。

感谢Abhijit Sarkar建议卷曲。我忘记了这一点，它揭示了这个问题。

Answer 3

查看代码@RequestParam(NetworkKeyNames.KEY_PAYLOAD)。我猜测NetworkKeyNames.KEY_PAYLOAD有一个字符串值。 Spring将尝试使用该字符串值作为参数名称，例如，如果NetworkKeyNames.KEY_PAYLOAD = "pay";需要发送给控制器的是pay=testing。

或你可以改变：

@RequestParam(NetworkKeyNames.KEY_PAYLOAD) String payload

到

 @RequestParam String payload

这将使用payload作为参数名称