REST_gRPC

UploadingFile_Client/src/main/java/Controllers/FileUploadController.java

-package Controllers;
-
-import Services.UploadFileService;
-import org.springframework.http.MediaType;
-import org.springframework.web.bind.annotation.*;
-import org.springframework.web.multipart.MultipartFile;
-
-@RestController
-public class FileUploadController {
-    private final UploadFileService uploadFileService;
-
-    public FileUploadController(UploadFileService uploadFileService) {
-        this.uploadFileService = uploadFileService;
-    }
-    @PostMapping(value = "/upload", consumes = MediaType.MULTIPART_FORM_DATA_VALUE)
-    public String uploadFile(@RequestParam("file") MultipartFile file) {
-        return this.uploadFileService.uploadFile(file);
-    }
-}

UploadingFile_Client/src/main/java/Services/UploadFileService.java

-package Services;
-
-import Uploading_Service.*;
-import com.google.protobuf.ByteString;
-import io.grpc.Metadata;
-import io.grpc.stub.MetadataUtils;
-import io.grpc.stub.StreamObserver;
-import net.devh.boot.grpc.client.inject.GrpcClient;
-import org.springframework.stereotype.Service;
-import org.springframework.web.multipart.MultipartFile;
-
-import java.io.IOException;
-import java.io.InputStream;
-import java.util.concurrent.CountDownLatch;
-
-@Service
-public class UploadFileService {
-   //Asynchronous stub of client
-    private final uploadingServiceGrpc.uploadingServiceStub client;
-    // @GrpcClient is help annotation refer to which server it requires to call
-    //file-upload is the key will be read from properties file
-    public UploadFileService(@GrpcClient(value = "file-upload") uploadingServiceGrpc.uploadingServiceStub client) {
-        this.client = client;
-    }
-
-    public String uploadFile(final MultipartFile multipartFile) {
-        //file name
-        String name;
-        //file size
-        int size;
-        //to read the bytes
-        InputStream inputStream;
-        name = multipartFile.getOriginalFilename();
-        try {
-            size = multipartFile.getBytes().length;
-            inputStream = multipartFile.getInputStream();
-        } catch (IOException e) {
-            return "unable to extract file info";
-        }
-        StringBuilder  response = new StringBuilder();
-        Metadata metadata = new Metadata();
-        CountDownLatch countDownLatch = new CountDownLatch(1);
-
-        metadata.put(Metadata.Key.of("file-meta-bin", Metadata.BINARY_BYTE_MARSHALLER),
-                FileMetadata.newBuilder()
-                        .setFileNameWithType(name)
-                        .setContentLength(size)
-                        .build()
-                        .toByteArray());
-        //using this object we will stream the file content to the server
-        StreamObserver<FileUploadRequest> fileUploadRequestStreamObserver = this.client
-                .withInterceptors(MetadataUtils.newAttachHeadersInterceptor(metadata))
-                .uploadFile(
-                        new StreamObserver<FileUploadResponse>() {
-                            @Override
-                            //called when server sends the response
-                            public void onNext(FileUploadResponse fileUploadResponse) {
-                                response.append(fileUploadResponse.getUploadStatus());
-
-                            }
-
-                            @Override
-                            //called when server send an error
-                            public void onError(Throwable throwable) {
-                                response.append(UploadStatus.FAILED);
-                                throwable.printStackTrace();
-                                countDownLatch.countDown();
-                            }
-
-                            @Override
-                            //called when server finish processing the request
-                            public void onCompleted() {
-                                countDownLatch.countDown();
-                            }
-                        });
-        //chunk data, i use the size 10 KB for each chunk
-        byte[] tenKB = new byte[10240];
-
-        int length;
-
-        try {
-            while ((length = inputStream.read(tenKB)) > 0) {
-                FileUploadRequest request = FileUploadRequest
-                        .newBuilder()
-                        .setFile(File.newBuilder().setContent(ByteString.copyFrom(tenKB, 0, length)))
-                        .build();
-                //sending the request that contain the chunk data of file
-                fileUploadRequestStreamObserver.onNext(request);
-            }
-            inputStream.close();
-            //notify the server we have completed sending the chunk data
-            fileUploadRequestStreamObserver.onCompleted();
-            //waiting server response
-            countDownLatch.await();
-
-        } catch (Exception e) {
-            e.printStackTrace();
-            response.append(UploadStatus.FAILED);
-        }
-        return response.toString();
-    }
-}