001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package org.apache.hadoop.yarn.client;
020    
021    import java.io.EOFException;
022    import java.net.ConnectException;
023    import java.net.InetSocketAddress;
024    import java.net.NoRouteToHostException;
025    import java.net.SocketException;
026    import java.net.UnknownHostException;
027    import java.security.PrivilegedAction;
028    import java.util.HashMap;
029    import java.util.Map;
030    import java.util.concurrent.TimeUnit;
031    
032    import org.apache.hadoop.classification.InterfaceAudience.Public;
033    import org.apache.hadoop.classification.InterfaceStability.Unstable;
034    import org.apache.hadoop.conf.Configuration;
035    import org.apache.hadoop.io.retry.RetryPolicies;
036    import org.apache.hadoop.io.retry.RetryPolicy;
037    import org.apache.hadoop.io.retry.RetryProxy;
038    import org.apache.hadoop.ipc.RetriableException;
039    import org.apache.hadoop.net.ConnectTimeoutException;
040    import org.apache.hadoop.security.UserGroupInformation;
041    import org.apache.hadoop.yarn.ipc.YarnRPC;
042    
043    import com.google.common.base.Preconditions;
044    
045    @Public
046    @Unstable
047    public class ServerProxy {
048    
049      protected static RetryPolicy createRetryPolicy(Configuration conf,
050          String maxWaitTimeStr, long defMaxWaitTime,
051          String connectRetryIntervalStr, long defRetryInterval) {
052        long maxWaitTime = conf.getLong(maxWaitTimeStr, defMaxWaitTime);
053        long retryIntervalMS =
054            conf.getLong(connectRetryIntervalStr, defRetryInterval);
055        if (maxWaitTime == -1) {
056          // wait forever.
057          return RetryPolicies.RETRY_FOREVER;
058        }
059    
060        Preconditions.checkArgument(maxWaitTime > 0, "Invalid Configuration. "
061            + maxWaitTimeStr + " should be a positive value.");
062        Preconditions.checkArgument(retryIntervalMS > 0, "Invalid Configuration. "
063            + connectRetryIntervalStr + "should be a positive value.");
064    
065        RetryPolicy retryPolicy =
066            RetryPolicies.retryUpToMaximumTimeWithFixedSleep(maxWaitTime,
067              retryIntervalMS, TimeUnit.MILLISECONDS);
068    
069        Map<Class<? extends Exception>, RetryPolicy> exceptionToPolicyMap =
070            new HashMap<Class<? extends Exception>, RetryPolicy>();
071        exceptionToPolicyMap.put(EOFException.class, retryPolicy);
072        exceptionToPolicyMap.put(ConnectException.class, retryPolicy);
073        exceptionToPolicyMap.put(NoRouteToHostException.class, retryPolicy);
074        exceptionToPolicyMap.put(UnknownHostException.class, retryPolicy);
075        exceptionToPolicyMap.put(ConnectTimeoutException.class, retryPolicy);
076        exceptionToPolicyMap.put(RetriableException.class, retryPolicy);
077        exceptionToPolicyMap.put(SocketException.class, retryPolicy);
078    
079        return RetryPolicies.retryByException(RetryPolicies.TRY_ONCE_THEN_FAIL,
080          exceptionToPolicyMap);
081      }
082    
083      @SuppressWarnings("unchecked")
084      protected static <T> T createRetriableProxy(final Configuration conf,
085          final Class<T> protocol, final UserGroupInformation user,
086          final YarnRPC rpc, final InetSocketAddress serverAddress,
087          RetryPolicy retryPolicy) {
088        T proxy = user.doAs(new PrivilegedAction<T>() {
089          @Override
090          public T run() {
091            return (T) rpc.getProxy(protocol, serverAddress, conf);
092          }
093        });
094        return (T) RetryProxy.create(protocol, proxy, retryPolicy);
095      }
096    }