/*
* 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.taskmanager;
import java.net.InetAddress;
import org.apache.flink.runtime.clusterframework.types.ResourceID;
import org.apache.flink.util.NetUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.annotation.Nonnull;
import static org.apache.flink.util.Preconditions.checkArgument;
import static org.apache.flink.util.Preconditions.checkNotNull;
/**
* This class encapsulates the connection information of a TaskManager.
* It describes the host where the TaskManager operates and its server port
* for data exchange. This class also contains utilities to work with the
* TaskManager's host name, which is used to localize work assignments.
*/
public class TaskManagerLocation implements Comparable<TaskManagerLocation>, java.io.Serializable {
private static final long serialVersionUID = -8254407801276350716L;
private static final Logger LOG = LoggerFactory.getLogger(TaskManagerLocation.class);
// ------------------------------------------------------------------------
/** The ID of the resource in which the TaskManager is started. This can be for example
* the YARN container ID, Mesos container ID, or any other unique identifier. */
private final ResourceID resourceID;
/** The network address that the TaskManager binds its sockets to */
private final InetAddress inetAddress;
/** The fully qualified host name of the TaskManager */
private final String fqdnHostName;
/** The pure hostname, derived from the fully qualified host name. */
private final String hostName;
/** The port that the TaskManager receive data transport connection requests at */
private final int dataPort;
/** The toString representation, eagerly constructed and cached to avoid repeated string building */
private final String stringRepresentation;
/**
* Constructs a new instance connection info object. The constructor will attempt to retrieve the instance's
* host name and domain name through the operating system's lookup mechanisms.
*
* @param inetAddress
* the network address the instance's task manager binds its sockets to
* @param dataPort
* the port instance's task manager expects to receive transfer envelopes on
*/
public TaskManagerLocation(ResourceID resourceID, InetAddress inetAddress, int dataPort) {
// -1 indicates a local instance connection info
checkArgument(dataPort > 0 || dataPort == -1, "dataPort must be > 0, or -1 (local)");
this.resourceID = checkNotNull(resourceID);
this.inetAddress = checkNotNull(inetAddress);
this.dataPort = dataPort;
// get FQDN hostname on this TaskManager.
String fqdnHostName;
try {
fqdnHostName = this.inetAddress.getCanonicalHostName();
}
catch (Throwable t) {
LOG.warn("Unable to determine the canonical hostname. Input split assignment (such as " +
"for HDFS files) may be non-local when the canonical hostname is missing.");
LOG.debug("getCanonicalHostName() Exception:", t);
fqdnHostName = this.inetAddress.getHostAddress();
}
this.fqdnHostName = fqdnHostName;
if (this.fqdnHostName.equals(this.inetAddress.getHostAddress())) {
// this happens when the name lookup fails, either due to an exception,
// or because no hostname can be found for the address
// take IP textual representation
this.hostName = this.fqdnHostName;
LOG.warn("No hostname could be resolved for the IP address {}, using IP address as host name. "
+ "Local input split assignment (such as for HDFS files) may be impacted.",
this.inetAddress.getHostAddress());
}
else {
this.hostName = NetUtils.getHostnameFromFQDN(this.fqdnHostName);
}
this.stringRepresentation = String.format(
"%s @ %s (dataPort=%d)", resourceID, fqdnHostName, dataPort);
}
// ------------------------------------------------------------------------
// Getters
// ------------------------------------------------------------------------
/**
* Gets the ID of the resource in which the TaskManager is started. The format of this depends
* on how the TaskManager is started:
* <ul>
* <li>If the TaskManager is started via YARN, this is the YARN container ID.</li>
* <li>If the TaskManager is started via Mesos, this is the Mesos container ID.</li>
* <li>If the TaskManager is started in standalone mode, or via a MiniCluster, this is a random ID.</li>
* <li>Other deployment modes can set the resource ID in other ways.</li>
* </ul>
*
* @return The ID of the resource in which the TaskManager is started
*/
public ResourceID getResourceID() {
return resourceID;
}
/**
* Returns the port instance's task manager expects to receive transfer envelopes on.
*
* @return the port instance's task manager expects to receive transfer envelopes on
*/
public int dataPort() {
return dataPort;
}
/**
* Returns the network address the instance's task manager binds its sockets to.
*
* @return the network address the instance's task manager binds its sockets to
*/
public InetAddress address() {
return inetAddress;
}
/**
* Gets the IP address where the TaskManager operates.
*
* @return The IP address.
*/
public String addressString() {
return inetAddress.toString();
}
/**
* Returns the fully-qualified domain name the TaskManager. If the name could not be
* determined, the return value will be a textual representation of the TaskManager's IP address.
*
* @return The fully-qualified domain name of the TaskManager.
*/
public String getFQDNHostname() {
return fqdnHostName;
}
/**
* Gets the hostname of the TaskManager. The hostname derives from the fully qualified
* domain name (FQDN, see {@link #getFQDNHostname()}):
* <ul>
* <li>If the FQDN is the textual IP address, then the hostname is also the IP address</li>
* <li>If the FQDN has only one segment (such as "localhost", or "host17"), then this is
* used as the hostname.</li>
* <li>If the FQDN has multiple segments (such as "worker3.subgroup.company.net"), then the first
* segment (here "worker3") will be used as the hostname.</li>
* </ul>
*
* @return The hostname of the TaskManager.
*/
public String getHostname() {
return hostName;
}
// --------------------------------------------------------------------------------------------
// Utilities
// --------------------------------------------------------------------------------------------
@Override
public String toString() {
return stringRepresentation;
}
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
else if (obj != null && obj.getClass() == TaskManagerLocation.class) {
TaskManagerLocation that = (TaskManagerLocation) obj;
return this.resourceID.equals(that.resourceID) &&
this.inetAddress.equals(that.inetAddress) &&
this.dataPort == that.dataPort;
}
else {
return false;
}
}
@Override
public int hashCode() {
return resourceID.hashCode() +
17 * inetAddress.hashCode() +
129 * dataPort;
}
@Override
public int compareTo(@Nonnull TaskManagerLocation o) {
// decide based on resource ID first
int resourceIdCmp = this.resourceID.getResourceIdString().compareTo(o.resourceID.getResourceIdString());
if (resourceIdCmp != 0) {
return resourceIdCmp;
}
// decide based on ip address next
byte[] thisAddress = this.inetAddress.getAddress();
byte[] otherAddress = o.inetAddress.getAddress();
if (thisAddress.length < otherAddress.length) {
return -1;
} else if (thisAddress.length > otherAddress.length) {
return 1;
} else {
for (int i = 0; i < thisAddress.length; i++) {
byte tb = thisAddress[i];
byte ob = otherAddress[i];
if (tb < ob) {
return -1;
} else if (tb > ob) {
return 1;
}
}
}
// addresses are identical, decide based on ports.
if (this.dataPort < o.dataPort) {
return -1;
} else if (this.dataPort > o.dataPort) {
return 1;
} else {
return 0;
}
}
}