BAEL-3595: Initial change for Multipart file upload (#10465)

* BAEL-3595: Initial change for Multipart file upload

* Corrected the name

* BAEL-3595: Added Tests

* Corrected the tests name

* Uncommented the code for live test

Co-authored-by: Amitabh Tiwari <Amitabh.Tiwari@maersk.com>

spring-cloud/spring-cloud-openfeign/pom.xml

@@ -37,12 +37,24 @@
             <groupId>io.github.openfeign</groupId>
             <artifactId>feign-okhttp</artifactId>
         </dependency>
-
+      
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>
+    
+        <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>
+	    
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>

spring-cloud/spring-cloud-openfeign/src/main/java/com/baeldung/cloud/openfeign/fileupload/config/FeignSupportConfig.java

@@ -0,0 +1,28 @@
+package com.baeldung.cloud.openfeign.fileupload.config;
+
+import org.springframework.beans.factory.ObjectFactory;
+import org.springframework.boot.autoconfigure.http.HttpMessageConverters;
+import org.springframework.cloud.openfeign.support.SpringEncoder;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.Primary;
+import org.springframework.context.annotation.Scope;
+import org.springframework.web.client.RestTemplate;
+
+import feign.codec.Encoder;
+import feign.form.spring.SpringFormEncoder;
+
+@Configuration
+public class FeignSupportConfig {
+    @Bean
+    @Primary
+    @Scope("prototype")
+    public Encoder multipartFormEncoder() {
+        return new SpringFormEncoder(new SpringEncoder(new ObjectFactory<HttpMessageConverters>() {
+            @Override
+            public HttpMessageConverters getObject() {
+                return new HttpMessageConverters(new RestTemplate().getMessageConverters());
+            }
+        }));
+    }
+}

spring-cloud/spring-cloud-openfeign/src/main/java/com/baeldung/cloud/openfeign/fileupload/controller/FileController.java

@@ -0,0 +1,28 @@
+package com.baeldung.cloud.openfeign.fileupload.controller;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestPart;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.cloud.openfeign.fileupload.service.UploadService;
+
+@RestController
+public class FileController {
+    
+    @Autowired
+    private UploadService service;
+    
+    @PostMapping(value = "/upload")
+    public String handleFileUpload(@RequestPart(value = "file") MultipartFile file) {
+        return service.uploadFile(file);
+    }
+    
+    @PostMapping(value = "/upload-mannual-client")
+    public boolean handleFileUploadWithManualClient(
+            @RequestPart(value = "file") MultipartFile file) {
+        return service.uploadFileWithManualClient(file);
+    }
+    
+}

spring-cloud/spring-cloud-openfeign/src/main/java/com/baeldung/cloud/openfeign/fileupload/service/UploadClient.java

@@ -0,0 +1,15 @@
+package com.baeldung.cloud.openfeign.fileupload.service;
+
+import org.springframework.cloud.openfeign.FeignClient;
+import org.springframework.http.MediaType;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestPart;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.cloud.openfeign.fileupload.config.FeignSupportConfig;
+
+@FeignClient(name = "file", url = "http://localhost:8081", configuration = FeignSupportConfig.class)
+public interface UploadClient {
+    @PostMapping(value = "/upload-file", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
+    String fileUpload(@RequestPart(value = "file") MultipartFile file);
+}

spring-cloud/spring-cloud-openfeign/src/main/java/com/baeldung/cloud/openfeign/fileupload/service/UploadResource.java

@@ -0,0 +1,16 @@
+package com.baeldung.cloud.openfeign.fileupload.service;
+
+import org.springframework.web.multipart.MultipartFile;
+
+import feign.Headers;
+import feign.Param;
+import feign.RequestLine;
+import feign.Response;
+
+public interface UploadResource {
+    
+    @RequestLine("POST /upload-file")
+    @Headers("Content-Type: multipart/form-data")
+    Response uploadFile(@Param("file") MultipartFile file);
+    
+}

spring-cloud/spring-cloud-openfeign/src/main/java/com/baeldung/cloud/openfeign/fileupload/service/UploadService.java

@@ -0,0 +1,29 @@
+package com.baeldung.cloud.openfeign.fileupload.service;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import org.springframework.web.multipart.MultipartFile;
+
+import feign.Feign;
+import feign.Response;
+import feign.form.spring.SpringFormEncoder;
+
+@Service
+public class UploadService {
+    private static final String HTTP_FILE_UPLOAD_URL = "http://localhost:8081";
+    
+    @Autowired
+    private UploadClient client;
+    
+    public boolean uploadFileWithManualClient(MultipartFile file) {
+        UploadResource fileUploadResource = Feign.builder().encoder(new SpringFormEncoder())
+                .target(UploadResource.class, HTTP_FILE_UPLOAD_URL);
+        Response response = fileUploadResource.uploadFile(file);
+        return response.status() == 200;
+    }
+    
+    public String uploadFile(MultipartFile file) {
+        return client.fileUpload(file);
+    }
+    
+}

spring-cloud/spring-cloud-openfeign/src/test/java/com/baeldung/cloud/openfeign/OpenFeignFileUploadLiveTest.java

@@ -0,0 +1,50 @@
+package com.baeldung.cloud.openfeign;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+
+import org.apache.commons.io.IOUtils;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.mock.web.MockMultipartFile;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.web.multipart.MultipartFile;
+
+import com.baeldung.cloud.openfeign.fileupload.service.UploadService;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest
+public class OpenFeignFileUploadLiveTest {
+    
+    @Autowired
+    private UploadService uploadService;
+    
+    private static String FILE_NAME = "fileupload.txt";
+    
+    @Test
+    public void whenFeignBuilder_thenFileUploadSuccess() throws IOException {
+        ClassLoader classloader = Thread.currentThread().getContextClassLoader();
+        File file = new File(classloader.getResource(FILE_NAME).getFile());
+        Assert.assertTrue(file.exists());
+        FileInputStream input = new FileInputStream(file);
+        MultipartFile multipartFile = new MockMultipartFile("file", file.getName(), "text/plain",
+                IOUtils.toByteArray(input));
+        Assert.assertTrue(uploadService.uploadFileWithManualClient(multipartFile));
+    }
+    
+    @Test
+    public void whenAnnotatedFeignClient_thenFileUploadSuccess() throws IOException {
+        ClassLoader classloader = Thread.currentThread().getContextClassLoader();
+        File file = new File(classloader.getResource(FILE_NAME).getFile());
+        Assert.assertTrue(file.exists());
+        FileInputStream input = new FileInputStream(file);
+        MultipartFile multipartFile = new MockMultipartFile("file", file.getName(), "text/plain",
+                IOUtils.toByteArray(input));
+        String uploadFile = uploadService.uploadFile(multipartFile);
+        Assert.assertNotNull(uploadFile);
+    }
+}