org.apache.flink.runtime.util.LeaderRetrievalUtils Maven / Gradle / Ivy
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* 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.util;
import org.apache.flink.runtime.leaderretrieval.LeaderRetrievalException;
import org.apache.flink.runtime.leaderretrieval.LeaderRetrievalListener;
import org.apache.flink.runtime.leaderretrieval.LeaderRetrievalService;
import org.apache.flink.runtime.net.ConnectionUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.net.InetAddress;
import java.time.Duration;
import java.util.UUID;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.TimeUnit;
/** Utility class to work with {@link LeaderRetrievalService} class. */
public class LeaderRetrievalUtils {
private static final Logger LOG = LoggerFactory.getLogger(LeaderRetrievalUtils.class);
/**
* Retrieves the leader akka url and the current leader session ID. The values are stored in a
* {@link LeaderConnectionInfo} instance.
*
* @param leaderRetrievalService Leader retrieval service to retrieve the leader connection
* information
* @param timeout Timeout when to give up looking for the leader
* @return LeaderConnectionInfo containing the leader's akka URL and the current leader session
* ID
* @throws LeaderRetrievalException
*/
public static LeaderConnectionInfo retrieveLeaderConnectionInfo(
LeaderRetrievalService leaderRetrievalService, Duration timeout)
throws LeaderRetrievalException {
LeaderConnectionInfoListener listener = new LeaderConnectionInfoListener();
try {
leaderRetrievalService.start(listener);
return listener.getLeaderConnectionInfoFuture()
.get(timeout.toMillis(), TimeUnit.MILLISECONDS);
} catch (Exception e) {
throw new LeaderRetrievalException(
"Could not retrieve the leader address and leader " + "session ID.", e);
} finally {
try {
leaderRetrievalService.stop();
} catch (Exception fe) {
LOG.warn("Could not stop the leader retrieval service.", fe);
}
}
}
public static InetAddress findConnectingAddress(
LeaderRetrievalService leaderRetrievalService, Duration timeout)
throws LeaderRetrievalException {
ConnectionUtils.LeaderConnectingAddressListener listener =
new ConnectionUtils.LeaderConnectingAddressListener();
try {
leaderRetrievalService.start(listener);
LOG.info(
"Trying to select the network interface and address to use "
+ "by connecting to the leading JobManager.");
LOG.info(
"TaskManager will try to connect for "
+ timeout
+ " before falling back to heuristics");
return listener.findConnectingAddress(timeout);
} catch (Exception e) {
throw new LeaderRetrievalException(
"Could not find the connecting address by "
+ "connecting to the current leader.",
e);
} finally {
try {
leaderRetrievalService.stop();
} catch (Exception fe) {
LOG.warn("Could not stop the leader retrieval service.", fe);
}
}
}
/**
* Helper class which is used by the retrieveLeaderConnectionInfo method to retrieve the
* leader's akka URL and the current leader session ID.
*/
public static class LeaderConnectionInfoListener implements LeaderRetrievalListener {
private final CompletableFuture connectionInfoFuture =
new CompletableFuture<>();
public CompletableFuture getLeaderConnectionInfoFuture() {
return connectionInfoFuture;
}
@Override
public void notifyLeaderAddress(String leaderAddress, UUID leaderSessionID) {
if (leaderAddress != null
&& !leaderAddress.equals("")
&& !connectionInfoFuture.isDone()) {
final LeaderConnectionInfo leaderConnectionInfo =
new LeaderConnectionInfo(leaderSessionID, leaderAddress);
connectionInfoFuture.complete(leaderConnectionInfo);
}
}
@Override
public void handleError(Exception exception) {
connectionInfoFuture.completeExceptionally(exception);
}
}
// ------------------------------------------------------------------------
/** Private constructor to prevent instantiation. */
private LeaderRetrievalUtils() {
throw new RuntimeException();
}
}