如何通过Spring cloud Feign发送POST请求

Question

这是我的虚拟接口

@FeignClient(
        name="mpi",
        url="${mpi.url}",
        configuration = FeignSimpleEncoderConfig.class
)
public interface MpiClient {

    @RequestMapping(method = RequestMethod.POST)
    public ResponseEntity<String> getPAReq(@QueryMap Map<String, String> queryMap
    );
}

和我的自定义配置

public class FeignSimpleEncoderConfig {
    public static final int FIVE_SECONDS = 5000;

    @Bean
    public Logger.Level feignLogger() {
        return Logger.Level.FULL;
    }

    @Bean
    public Request.Options options() {
        return new Request.Options(FIVE_SECONDS, FIVE_SECONDS);
    }

    @Bean 
    @Scope("prototype")
    public Feign.Builder feignBuilder() {
        return Feign.builder()
                .encoder(new FormEncoder());
    }
}

如果我像这样发送请求，我会看到我的请求发送了Content-Type:application/JSON；字符集=UTF-8。但是如果我设置了内容类型

consumes = "application/x-www-form-urlencoded"

我收到了这条错误消息。

feign.codec.EncodeException: Could not write request: no suitable HttpMessageConverter found for request type [java.util.HashMap] and content type [application/x-www-form-urlencoded]
    at org.springframework.cloud.netflix.feign.support.SpringEncoder.encode(SpringEncoder.java:108) ~[spring-cloud-netflix-core-1.1.7.RELEASE.jar:1.1.7.RELEASE]

如何发送POST请求，我认为我应该用编码器做更多的东西。感谢您的帮助。

Answer 1

为处理表单编码请求指定正确的编码器

您可以指定多编码器示例json/xml/formhttpurl编码

@Bean
public Encoder feignEncoder() {
    ObjectFactory<HttpMessageConverters> objectFactory = () ->
            new HttpMessageConverters(new FormHttpMessageConverter());
    return new SpringEncoder(objectFactory);
}

重要表单HttpMessageConverter仅序列化多值映射子类

Answer 2

在我看来，Map对表单体无效。MultiValueMap工作正常。

假装客户：

@FeignClient(name = "name", url="url", configuration = FromUrlEncodedClientConfiguration.class)
public interface PayPalFeignClient {

    @RequestMapping(value = "/", method = POST, consumes = MediaType.APPLICATION_FORM_URLENCODED_VALUE)
    @Headers("Content-Type: application/x-www-form-urlencoded")
    String foo(MultiValueMap<String, ?> formParams);
}

配置：

@Configuration
public class FromUrlEncodedClientConfiguration {

    @Autowired
    private ObjectFactory<HttpMessageConverters> messageConverters;

    @Bean
    @Primary
    @Scope(SCOPE_PROTOTYPE)
    Encoder feignFormEncoder() {
        return new FormEncoder(new SpringEncoder(this.messageConverters));
    }
}

梯度依赖性:

compile group: 'io.github.openfeign.form', name: 'feign-form', version: '2.0.2'
compile group: 'io.github.openfeign.form', name: 'feign-form-spring', version: '2.0.5'

之后，您所要做的就是使用多值映射参数调用它。

Answer 3

首先，您应该这样更改您的外观界面：

@FeignClient (
    configuration = FeignSimpleEncoderConfig.class
)
public interface MpiClient {
   @RequestMapping(method = RequestMethod.POST)
   ResponseEntity<String> getPAReq(Map<String, ?> queryMap);
}

然后，您应该在feign配置期间设置编码器:

public class FeignSimpleEncoderConfig {
    @Bean
    public Encoder encoder() {
        return new FormEncoder();
    }
}