001/* 002 * (C) Copyright 2006-2014 Nuxeo SA (http://nuxeo.com/) and others. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016package org.nuxeo.ecm.core.redis; 017 018import org.nuxeo.ecm.core.redis.retry.ExponentialBackofDelay; 019import org.nuxeo.ecm.core.redis.retry.Retry; 020import org.nuxeo.ecm.core.redis.retry.Retry.ContinueException; 021import org.nuxeo.ecm.core.redis.retry.Retry.FailException; 022 023import org.nuxeo.ecm.core.redis.retry.SimpleDelay; 024import redis.clients.jedis.Jedis; 025import redis.clients.jedis.JedisPubSub; 026import redis.clients.jedis.exceptions.JedisConnectionException; 027import redis.clients.util.Pool; 028 029public class RedisFailoverExecutor extends RedisAbstractExecutor { 030 031 protected final int timeout; 032 033 protected final RedisExecutor executor; 034 035 public RedisFailoverExecutor(int timeout, RedisExecutor base) { 036 this.timeout = timeout; 037 executor = base; 038 } 039 040 @Override 041 public <T> T execute(final RedisCallable<T> callable) throws JedisConnectionException { 042 // Retry the operation with an exponential backoff limited by a configurable timeout 043 return executeWithRetryPolicy(callable, new ExponentialBackofDelay(1, timeout)); 044 } 045 046 @Override 047 public void subscribe(JedisPubSub subscriber, String channel) throws JedisConnectionException { 048 // Here it is a long running operation, we never give up retry every 2s 049 executeWithRetryPolicy(jedis -> { 050 jedis.subscribe(subscriber, channel); 051 return null; 052 }, new SimpleDelay(2000, Integer.MAX_VALUE)); 053 } 054 055 protected <T> T executeWithRetryPolicy(final RedisCallable<T> callable, Retry.Policy policy) { 056 try { 057 return new Retry().retry(new Retry.Block<T>() { 058 059 @Override 060 public T retry() throws ContinueException, FailException { 061 try { 062 return executor.execute(callable); 063 } catch (JedisConnectionException cause) { 064 throw new ContinueException(cause); 065 } 066 } 067 068 }, policy); 069 } catch (FailException cause) { 070 throw new JedisConnectionException("Cannot reconnect to jedis ..", cause); 071 } 072 } 073 074 @Override 075 public Pool<Jedis> getPool() { 076 return executor.getPool(); 077 } 078 079}