Add example of replication configuration using redis-sentinel.

examples/replication_sentinel.php

@@ -0,0 +1,64 @@
+<?php
+
+/*
+ * This file is part of the Predis package.
+ *
+ * (c) Daniele Alessandri <suppakilla@gmail.com>
+ *
+ * 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.
+
+use Predis\Connection\Aggregate\SentinelReplication;
+
+// 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($sentinels, array(
+    'service' => 'mymaster',
+    'aggregate' => function () {
+        return function ($sentinels, $options) {
+            return new SentinelReplication($sentinels, $options->service, $options->connections);
+        };
+    },
+));
+
+// Read operation.
+$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? yes.
+Now 'foo' has been set to 'bar' on master!
+We fetched 'foo' from master and its value is 'bar'.
+*/