grpc java大文件上传实现
时间: 2023-08-02 18:08:17 浏览: 69
实现大文件上传的一种常见方式是使用分块上传(Chunked Transfer Encoding),即将大文件分成多个块,每个块独立上传,最后将所有块合并成完整文件。在 gRPC 中,可以使用流(Stream)的方式实现分块上传。
以下是一个简单的 gRPC Java 大文件上传示例:
1. 定义 gRPC 服务
```
service FileService {
rpc uploadFile(stream FileChunk) returns (UploadStatus);
}
message FileChunk {
bytes data = 1;
}
message UploadStatus {
bool success = 1;
}
```
2. 实现服务端逻辑
```
public class FileServiceImpl extends FileServiceGrpc.FileServiceImplBase {
private static final Logger logger = Logger.getLogger(FileServiceImpl.class.getName());
private Path filePath;
private OutputStream outputStream;
@Override
public StreamObserver<FileChunk> uploadFile(final StreamObserver<UploadStatus> responseObserver) {
return new StreamObserver<FileChunk>() {
@Override
public void onNext(FileChunk chunk) {
try {
outputStream.write(chunk.getData().toByteArray());
outputStream.flush();
} catch (IOException e) {
logger.log(Level.WARNING, "Error writing file chunk", e);
responseObserver.onError(e);
}
}
@Override
public void onError(Throwable t) {
logger.log(Level.WARNING, "File upload failed", t);
try {
outputStream.close();
} catch (IOException e) {
logger.log(Level.WARNING, "Error closing output stream", e);
}
}
@Override
public void onCompleted() {
try {
outputStream.close();
responseObserver.onNext(UploadStatus.newBuilder().setSuccess(true).build());
responseObserver.onCompleted();
} catch (IOException e) {
logger.log(Level.WARNING, "Error closing output stream", e);
responseObserver.onError(e);
}
}
};
}
}
```
3. 实现客户端逻辑
```
public class FileClient {
private static final Logger logger = Logger.getLogger(FileClient.class.getName());
private final ManagedChannel channel;
private final FileServiceGrpc.FileServiceStub stub;
public FileClient(String host, int port) {
channel = ManagedChannelBuilder.forAddress(host, port).usePlaintext().build();
stub = FileServiceGrpc.newStub(channel);
}
public void uploadFile(Path filePath) throws IOException {
FileInputStream inputStream = new FileInputStream(filePath.toFile());
StreamObserver<FileChunk> requestObserver = stub.uploadFile(new StreamObserver<UploadStatus>() {
@Override
public void onNext(UploadStatus status) {
logger.info("File uploaded successfully");
}
@Override
public void onError(Throwable t) {
logger.log(Level.WARNING, "File upload failed", t);
}
@Override
public void onCompleted() {
logger.info("File upload completed");
}
});
byte[] buffer = new byte[8192];
int bytesRead;
while ((bytesRead = inputStream.read(buffer)) != -1) {
byte[] chunkData = Arrays.copyOf(buffer, bytesRead);
requestObserver.onNext(FileChunk.newBuilder().setData(ByteString.copyFrom(chunkData)).build());
}
requestObserver.onCompleted();
}
public void shutdown() throws InterruptedException {
channel.shutdown().awaitTermination(5, TimeUnit.SECONDS);
}
}
```
以上代码仅为示例,实际应用中需要考虑更多细节,例如断点续传、上传进度显示等。