Feign-Form Encoder-實現基於Spring MultipartFile 和Spring FeignClient 表單文件上傳

Feign-Form Encoder-實現基於Spring MultipartFile 和Spring FeignClient 表單文件上傳

OpenFeign Form Encoder 支持對application/x-www-form-urlencoded and multipart/form-data 格式的表單數據編碼。支持基於Spring MultipartFile 和Spring Cloud Netflix @FeignClient框架的表單文件上傳。

1、在 pom.xml文件引入如下依賴:

<dependencies>
  <dependency>
    <groupId>io.github.openfeign.form</groupId>
    <artifactId>feign-form</artifactId>
    <version>3.8.0</version>
  </dependency>
  <dependency>
    <groupId>io.github.openfeign.form</groupId>
    <artifactId>feign-form-spring</artifactId>
    <version>3.8.0</version>
  </dependency>
</dependencies>

2、如何使用FeignForm Encoder

@FeignClient(
    name = "file-upload-service",
    configuration = FileUploadServiceClient.MultipartSupportConfig.class
)
public interface FileUploadServiceClient extends IFileUploadServiceClient {

  public class MultipartSupportConfig {

    @Autowired
    private ObjectFactory<HttpMessageConverters> messageConverters;

    @Bean
    public Encoder feignFormEncoder () {
      return new SpringFormEncoder(new SpringEncoder(messageConverters));
    }
  }
}

或者你不需要使用Spring的標準 encoder:

@FeignClient(
    name = "file-upload-service",
    configuration = FileUploadServiceClient.MultipartSupportConfig.class
)
public interface FileUploadServiceClient extends IFileUploadServiceClient {

  public class MultipartSupportConfig {

    @Bean
    public Encoder feignFormEncoder () {
      return new SpringFormEncoder();
    }
  }
}

這樣就可以利用Spring FeignClient 框架實現Spring MultipartFile 格式文件表單提交。

3、其他特性

tf-haotrii-pham提供了一個特性—利用Apache commons-fileupload庫處理multipart響應的解析，body 數據部分作爲字節數組保存在內存中。要使用這個特性，需要在解碼器的消息轉換器列表中包含SpringManyMultipartFilesReader，並讓Feign客戶端返回一個MultipartFile數組:

@FeignClient(
    name = "${feign.name}",
    url = "${feign.url}"
    configuration = DownloadClient.ClientConfiguration.class
)
public interface DownloadClient {

  @RequestMapping("/multipart/download/{fileId}")
  MultipartFile[] download(@PathVariable("fileId") String fileId);

  class ClientConfiguration {

    @Autowired
    private ObjectFactory<HttpMessageConverters> messageConverters;

    @Bean
    public Decoder feignDecoder () {
      List<HttpMessageConverter<?>> springConverters =
            messageConverters.getObject().getConverters();

      List<HttpMessageConverter<?>> decoderConverters =
            new ArrayList<HttpMessageConverter<?>>(springConverters.size() + 1);

      decoderConverters.addAll(springConverters);
      decoderConverters.add(new SpringManyMultipartFilesReader(4096));

      HttpMessageConverters httpMessageConverters = new HttpMessageConverters(decoderConverters);

      return new SpringDecoder(new ObjectFactory<HttpMessageConverters>() {

        @Override
        public HttpMessageConverters getObject() {
          return httpMessageConverters;
        }
      });
    }
  }
}

參考

https://github.com/OpenFeign/feign-form