Retwis ported to modern Redis data types.

The example (and related documentation at redis.io) was not updated for
5 years. Redis had no sorted sets and hashes when the original code was
written (!). An update was really needed.

We also use a modern PHP client now: Predis. A copy is shipped within
this repository to make life easier to newcomers trying Redis for the
first time via this example.

Predis/Option/ClientOptions.php

@@ -0,0 +1,125 @@
+<?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.
+ */
+
+namespace Predis\Option;
+
+/**
+ * Class that manages client options with filtering and conversion.
+ *
+ * @author Daniele Alessandri <suppakilla@gmail.com>
+ */
+class ClientOptions implements ClientOptionsInterface
+{
+    private $handlers;
+    private $defined;
+    private $options = array();
+
+    /**
+     * @param array $options Array of client options.
+     */
+    public function __construct(Array $options = array())
+    {
+        $this->handlers = $this->initialize($options);
+        $this->defined = array_fill_keys(array_keys($options), true);
+    }
+
+    /**
+     * Ensures that the default options are initialized.
+     *
+     * @return array
+     */
+    protected function getDefaultOptions()
+    {
+        return array(
+            'profile' => new ClientProfile(),
+            'connections' => new ClientConnectionFactory(),
+            'cluster' => new ClientCluster(),
+            'replication' => new ClientReplication(),
+            'prefix' => new ClientPrefix(),
+            'exceptions' => new ClientExceptions(),
+        );
+    }
+
+    /**
+     * Initializes client options handlers.
+     *
+     * @param  array $options List of client options values.
+     * @return array
+     */
+    protected function initialize(Array $options)
+    {
+        $handlers = $this->getDefaultOptions();
+
+        foreach ($options as $option => $value) {
+            if (isset($handlers[$option])) {
+                $handler = $handlers[$option];
+                $handlers[$option] = function ($options) use ($handler, $value) {
+                    return $handler->filter($options, $value);
+                };
+            } else {
+                $this->options[$option] = $value;
+            }
+        }
+
+        return $handlers;
+    }
+
+    /**
+     * Checks if the specified option is set.
+     *
+     * @param  string $option Name of the option.
+     * @return bool
+     */
+    public function __isset($option)
+    {
+        return isset($this->defined[$option]);
+    }
+
+    /**
+     * Returns the value of the specified option.
+     *
+     * @param  string $option Name of the option.
+     * @return mixed
+     */
+    public function __get($option)
+    {
+        if (isset($this->options[$option])) {
+            return $this->options[$option];
+        }
+
+        if (isset($this->handlers[$option])) {
+            $handler = $this->handlers[$option];
+            $value = $handler instanceof OptionInterface ? $handler->getDefault($this) : $handler($this);
+            $this->options[$option] = $value;
+
+            return $value;
+        }
+    }
+
+    /**
+     * Returns the default value for the specified option.
+     *
+     * @param  string|OptionInterface $option Name or instance of the option.
+     * @return mixed
+     */
+    public function getDefault($option)
+    {
+        if ($option instanceof OptionInterface) {
+            return $option->getDefault($this);
+        }
+
+        $options = $this->getDefaultOptions();
+
+        if (isset($options[$option])) {
+            return $options[$option]->getDefault($this);
+        }
+    }
+}