org.apache.flink.runtime.blob.BlobOutputStream Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.runtime.blob;
import org.apache.flink.api.common.JobID;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.annotation.Nullable;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.security.MessageDigest;
import java.util.Arrays;
import static org.apache.flink.runtime.blob.BlobServerProtocol.BUFFER_SIZE;
import static org.apache.flink.runtime.blob.BlobServerProtocol.JOB_RELATED_CONTENT;
import static org.apache.flink.runtime.blob.BlobServerProtocol.JOB_UNRELATED_CONTENT;
import static org.apache.flink.runtime.blob.BlobServerProtocol.PUT_OPERATION;
import static org.apache.flink.runtime.blob.BlobServerProtocol.RETURN_ERROR;
import static org.apache.flink.runtime.blob.BlobServerProtocol.RETURN_OKAY;
import static org.apache.flink.runtime.blob.BlobUtils.writeLength;
/**
* The BLOB output stream is a special implementation of an {@link OutputStream} to send data vi PUT
* to the BLOB server.
*/
final class BlobOutputStream extends OutputStream {
private static final Logger LOG = LoggerFactory.getLogger(BlobOutputStream.class);
private final BlobKey.BlobType blobType;
private final OutputStream socketStream;
private final Socket socket;
private final MessageDigest md;
BlobOutputStream(JobID jobID, BlobKey.BlobType blobType, Socket socket) throws IOException {
this.blobType = blobType;
if (socket.isClosed()) {
throw new IllegalStateException(
"BLOB Client is not connected. "
+ "Client has been shut down or encountered an error before.");
}
this.socket = socket;
this.socketStream = socket.getOutputStream();
this.md = BlobUtils.createMessageDigest();
sendPutHeader(socketStream, jobID, blobType);
}
@Override
public void write(int b) throws IOException {
writeLength(1, socketStream);
socketStream.write(b);
md.update((byte) b);
}
@Override
public void write(byte[] b, int off, int len) throws IOException {
// Send the value in iterations of BUFFER_SIZE
int remainingBytes = len;
while (remainingBytes > 0) {
// want a common code path for byte[] and InputStream at the BlobServer
// -> since for InputStream we don't know a total size beforehand, send lengths
// iteratively
final int bytesToSend = Math.min(BUFFER_SIZE, remainingBytes);
writeLength(bytesToSend, socketStream);
socketStream.write(b, off, bytesToSend);
// Update the message digest
md.update(b, off, bytesToSend);
remainingBytes -= bytesToSend;
off += bytesToSend;
}
}
public BlobKey finish() throws IOException {
// send -1 as the stream end
writeLength(-1, socketStream);
// Receive blob key and compare
final InputStream is = this.socket.getInputStream();
return receiveAndCheckPutResponse(is, md, blobType);
}
/**
* Constructs and writes the header data for a PUT request to the given output stream.
*
* @param outputStream the output stream to write the PUT header data to
* @param jobId the ID of job the BLOB belongs to (or null if job-unrelated)
* @param blobType whether the BLOB should become permanent or transient
* @throws IOException thrown if an I/O error occurs while writing the header data to the output
* stream
*/
private static void sendPutHeader(
OutputStream outputStream, @Nullable JobID jobId, BlobKey.BlobType blobType)
throws IOException {
// Signal type of operation
outputStream.write(PUT_OPERATION);
if (jobId == null) {
outputStream.write(JOB_UNRELATED_CONTENT);
} else {
outputStream.write(JOB_RELATED_CONTENT);
outputStream.write(jobId.getBytes());
}
outputStream.write(blobType.ordinal());
}
/**
* Reads the response from the input stream and throws in case of errors.
*
* @param is stream to read from
* @param md message digest to check the response against
* @param blobType whether the BLOB should be permanent or transient
* @throws IOException if the response is an error, the message digest does not match or reading
* the response failed
*/
private static BlobKey receiveAndCheckPutResponse(
InputStream is, MessageDigest md, BlobKey.BlobType blobType) throws IOException {
int response = is.read();
if (response < 0) {
throw new EOFException("Premature end of response");
} else if (response == RETURN_OKAY) {
BlobKey remoteKey = BlobKey.readFromInputStream(is);
byte[] localHash = md.digest();
if (blobType != remoteKey.getType()) {
throw new IOException("Detected data corruption during transfer");
}
if (!Arrays.equals(localHash, remoteKey.getHash())) {
throw new IOException("Detected data corruption during transfer");
}
return remoteKey;
} else if (response == RETURN_ERROR) {
Throwable cause = BlobUtils.readExceptionFromStream(is);
throw new IOException("Server side error: " + cause.getMessage(), cause);
} else {
throw new IOException("Unrecognized response: " + response + '.');
}
}
}