无法写入请求：没有找到适合带有 Feign 的请求类型的 HttpMessageConverter答案

【问题标题】：Could not write request: no suitable HttpMessageConverter found for request type with Feign无法写入请求：没有找到适合带有 Feign 的请求类型的 HttpMessageConverter
【发布时间】：2021-07-26 07:51:44
【问题描述】：

我想使用 Spring Cloud Feign 客户端实现请求。我试过这个：

Feign 客户端：

@FeignClient(name = "mail-service", url = "mail-service")
public interface EmailClient {

    @RequestMapping(method = RequestMethod.POST, value = "/register")
    void setUserRegistration(RegisterUserDTO registerUserDTO);

    @RequestMapping(method = RequestMethod.POST, value = "/password_reset")
    void setUserPasswordReset(PasswordResetDTO passwordResetDTO);
}

请求 DTO：

public class RegisterUserDTO {
    private int id;

    public RegisterUserDTO() {
    }
}

控制器：

@Autowire
EmailClient emailClient;

@PostMapping("/dummy")
public ResponseEntity<?> test() {

    RegisterUserDTO obj = new RegisterUserDTO();

    emailClient.setUserRegistration(obj);

    return ok().build();
}

Feign 配置：

feign:
    client:
        config:
            default:
                connectTimeout: 5000
                readTimeout: 5000
                loggerLevel: basic
eureka:
    client:
        serviceUrl:
            defaultZone: ${EUREKA_URI:http://localhost:8761/eureka}
    instance:
        preferIpAddress: true

但是当我发出 POST 请求时，我得到了异常：

22:50:05.325 [http-nio-8090-exec-1] DEBUG DispatcherServlet[logResult:1101] - Failed to complete request: feign.codec.EncodeException: Could not write request: no suitable HttpMessageConverter found for request type [org.engine.plugin.dto.RegisterUserDTO]
22:50:05.328 [http-nio-8090-exec-1] DEBUG HstsHeaderWriter[writeHeaders:169] - Not injecting HSTS header since it did not match the requestMatcher org.springframework.security.web.header.writers.HstsHeaderWriter$SecureRequestMatcher@461d6969
22:50:05.329 [http-nio-8090-exec-1] DEBUG SecurityContextPersistenceFilter[doFilter:119] - SecurityContextHolder now cleared, as request processing completed
22:50:05.334 [http-nio-8090-exec-1] ERROR [dispatcherServlet][log:175] - Servlet.service() for servlet [dispatcherServlet] in context with path [/engine] threw exception [Request processing failed; nested exception is feign.codec.EncodeException: Could not write request: no suitable HttpMessageConverter found for request type [org.engine.plugin.dto.RegisterUserDTO]] with root cause
feign.codec.EncodeException: Could not write request: no suitable HttpMessageConverter found for request type [org.engine.plugin.dto.RegisterUserDTO]

你知道我该如何解决这个问题吗？

【问题讨论】：

尝试将 getter 和 setter 添加到您的 POJO RegisterUserDTO。
我添加了 getter/setter 但我仍然得到同样的错误。
这就是问题所在。谢谢！

标签： spring spring-boot spring-cloud spring-cloud-feign feign

【解决方案1】：

在我的例子中，我使用了 openfeign 依赖，而没有 spring-boot-starter-web。添加此依赖项后，错误消失。可能是因为它包含所需的 json 映射器。

【讨论】：

【解决方案2】：

是的，您没有在 DTO 中添加 getter 方法。

public class RegisterUserDTO {
    

    private int id;
    public RegisterUserDTO() {
    }
    public int getId() {
     return id;
    }


}

查看我添加的代码。

【讨论】：