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<?php
 /*
 * This file is part of the Predis package.
 *
 * (c) Daniele Alessandri <[email protected]>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
 
 require __DIR__.'/shared.php';
 
 // Predis supports redis-sentinel to provide high availability in master / slave
 // scenarios. The only but relevant difference with a basic replication scenario
 // is that sentinel servers can manage the master server and its slaves based on
 // their state, which means that they are able to provide an authoritative and
 // updated configuration to clients thus avoiding static configurations for the
 // replication servers and their roles.
 
 // Instead of connection parameters pointing to redis nodes, we provide a list
 // of instances of redis-sentinel. Users should always provide a timeout value
 // low enough to not hinder operations just in case a sentinel is unreachable
 // but Predis uses a default value of 100 milliseconds for sentinel parameters
 // without an explicit timeout value.
 //
 // NOTE: in real-world scenarios sentinels should be running on different hosts!
 $sentinels = array(
 'tcp://127.0.0.1:5380?timeout=0.100',
 'tcp://127.0.0.1:5381?timeout=0.100',
 'tcp://127.0.0.1:5382?timeout=0.100',
 );
 
 $client = new Predis\Client($sentinels, array(
 'replication' => 'sentinel',
 'service' => 'mymaster',
 ));
 
 // Read operation.
 $exists = $client->exists('foo') ? 'yes' : 'no';
 $current = $client->getConnection()->getCurrent()->getParameters();
 echo "Does 'foo' exist on {$current->alias}? $exists.", PHP_EOL;
 
 // Write operation.
 $client->set('foo', 'bar');
 $current = $client->getConnection()->getCurrent()->getParameters();
 echo "Now 'foo' has been set to 'bar' on {$current->alias}!", PHP_EOL;
 
 // Read operation.
 $bar = $client->get('foo');
 $current = $client->getConnection()->getCurrent()->getParameters();
 echo "We fetched 'foo' from {$current->alias} and its value is '$bar'.", PHP_EOL;
 
 /* OUTPUT:
 Does 'foo' exist on slave-127.0.0.1:6381? yes.
 Now 'foo' has been set to 'bar' on master!
 We fetched 'foo' from master and its value is 'bar'.
 */
 
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