在Spring Cloud封装的Feign中并不直接支持传文件，但可以通过引入Feign的扩展包来实现，本文就来具体说说如何实现。需要JAVA Spring Cloud大型企业分布式微服务云构建的B2B2C电子商务平台源码 一零三八七七四六二六

服务提供方（接收文件）

服务提供方的实现比较简单，就按Spring MVC的正常实现方式即可，比如：

@EnableFeignClients
@EnableDiscoveryClient
@SpringBootApplication
public class Application {@RestControllerpublic class UploadController {@PostMapping(value = "/uploadFile", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)public String handleFileUpload(@RequestPart(value = "file") MultipartFile file) {return file.getName();}}public static void main(String[] args) {new SpringApplicationBuilder(Application.class).web(true).run(args);}}
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服务消费方（发送文件）

在服务消费方由于会使用Feign客户端，所以在这里需要在引入feign对表单提交的依赖，具体如下：

<dependency><groupId>io.github.openfeign.form</groupId><artifactId>feign-form</artifactId><version>3.0.3</version>
</dependency>
<dependency><groupId>io.github.openfeign.form</groupId><artifactId>feign-form-spring</artifactId><version>3.0.3</version>
</dependency>
<dependency><groupId>commons-fileupload</groupId><artifactId>commons-fileupload</artifactId><version>1.3.3</version>
</dependency>
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定义文件上传方的应用主类和FeignClient，假设服务提供方的服务名为 eureka-feign-upload-server

@EnableFeignClients
@EnableDiscoveryClient
@SpringBootApplication
public class Application {public static void main(String[] args) {new SpringApplicationBuilder(Application.class).web(true).run(args);}}@FeignClient(value = "upload-server", configuration = UploadService.MultipartSupportConfig.class)
public interface UploadService {@PostMapping(value = "/uploadFile", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)String handleFileUpload(@RequestPart(value = "file") MultipartFile file);@Configurationclass MultipartSupportConfig {@Beanpublic Encoder feignFormEncoder() {return new SpringFormEncoder();}}}
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在启动了服务提供方之后，尝试在服务消费方编写测试用例来通过上面定义的Feign客户端来传文件，比如：

@Slf4j
@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest
public class UploadTester {@Autowiredprivate UploadService uploadService;@Test@SneakyThrowspublic void testHandleFileUpload() {File file = new File("upload.txt");DiskFileItem fileItem = (DiskFileItem) new DiskFileItemFactory().createItem("file",MediaType.TEXT_PLAIN_VALUE, true, file.getName());try (InputStream input = new FileInputStream(file); OutputStream os = fileItem.getOutputStream()) {IOUtils.copy(input, os);} catch (Exception e) {throw new IllegalArgumentException("Invalid file: " + e, e);}MultipartFile multi = new CommonsMultipartFile(fileItem);log.info(uploadService.handleFileUpload(multi));}}
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java B2B2C 仿淘宝电子商城系统