Add support for Redis in addition to System V queues

models/RedisQueue.php

@@ -0,0 +1,108 @@
+<?php
+
+/*
+ * This file is part of RaspiSMS.
+ *
+ * (c) Pierre-Lin Bonnemaison <plebwebsas@gmail.com>
+ *
+ * This source file is subject to the GPL-3.0 license that is bundled
+ * with this source code in the file LICENSE.
+ */
+
+namespace models;
+
+use Exception;
+
+/**
+ *
+ */
+class RedisQueue implements Queue
+{
+    private \Redis $redis;
+    private $group;
+    private $consumer;
+    private $id;
+
+    /**
+     * A Redis queue to store and exchange messages using redis streams
+     * routing is based on queue uniq id as stream name, combined with ':tag' if routing is needed, messages are stored as json
+     * @param string $id : A unique identifier for the queue
+     * @param array $redis_parameters : Parameters for the redis server, such as host, port, etc. Default to a basic local redis on port 6379
+     * @param string $group : Name to use for the redis group that must read this queue, default to 'default'
+     * @param string $consumer : Name to use for the redis consumer in the group that must read this queue, default to 'default'
+     */
+    public function __construct($id, $redis_parameters = [], $group = 'default', $consumer = 'default')
+    {
+        $this->id = $id;
+        $this->redis = new \Redis();
+        $success = $this->redis->connect($redis_parameters['host'], intval($redis_parameters['port']), 1, '', 0, 0, ['auth' => $redis_parameters['auth']]);
+        
+        if (!$success) 
+        {
+            throw new \Exception('Failed to connect to redis server !');
+        }
+        
+        $this->group = $group;
+        $this->consumer = $consumer;
+    }
+
+    /**
+     * Add a message to the queue
+     * 
+     * @param string $message : The message to add to the queue
+     * @param ?string $tag : A tag to associate to the message for routing purposes, if null will add to general queue
+     */
+    public function push($message, ?string $tag = null)
+    {
+        $stream = $this->id . ($tag !== null ? ":$tag" : '');
+        $success = $this->redis->xAdd($stream, '*', ['message' => $message]);
+
+        if (!$success) 
+        {
+            throw new \Exception('Failed to push a message !');
+        }
+
+        return true;
+    }
+
+    /**
+     * Read the older message in the queue
+     * 
+     * @return mixed $message : The oldest message or null if no message found, can be anything
+     * @param ?string $tag : A tag to associate to the message for routing purposes, if null will read from general queue
+     * @param mixed : The message to add to the queue, can be anything, the queue will have to treat it by itself
+     */
+    public function read(?string $tag = null)
+    {
+        $stream = $this->id . ($tag !== null ? ":$tag" : '');
+
+        // Create the consumer group if it doesn't already exist
+        try 
+        {
+            $this->redis->xGroup('CREATE', $stream, $this->group, '$', true);
+        } 
+        catch (Exception $e) 
+        {
+            // Ignore error if the group already exists
+        }
+
+        // Read a single message starting from the oldest (>)
+        $messages = $this->redis->xReadGroup($this->group, $this->consumer, [$stream => '>'], 1);
+        if (!count($messages))
+        {
+            return null;
+        }
+
+        // Find the message, acknowledge it and return it
+        foreach ($messages as $stream_name => $entries) 
+        {
+            foreach ($entries as $message_id => $message) 
+            {
+                $success = $this->redis->xAck($stream, $this->group, [$message_id]);
+                return $message['message'];
+            }
+        }
+
+        return null;
+    }
+}