feature #18172 [Cache] Redis adapter (gcds, nicolas-grekas)

This PR was merged into the 3.1-dev branch.

Discussion
----------

[Cache] Redis adapter

| Q             | A
| ------------- | ---
| Branch        | master
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #17441
| License       | MIT
| Doc PR        | -

Commits
-------

6b7a1fc [Cache] Finish Redis adapter
4893cbc Added RedisAdapter

.travis.yml

@@ -31,7 +31,9 @@ cache:
         - .phpunit
         - php-$MIN_PHP
 
-services: mongodb
+services:
+    - mongodb
+    - redis-server
 
 before_install:
     # Matrix lines for intermediate PHP versions are skipped for pull requests
@@ -48,6 +50,7 @@ before_install:
     - if [[ $TRAVIS_PHP_VERSION = 5.* && ! $deps ]]; then (cd src/Symfony/Component/Debug/Resources/ext && phpize && ./configure && make && echo extension = $(pwd)/modules/symfony_debug.so >> $INI_FILE); fi;
     - if [[ $TRAVIS_PHP_VERSION = 5.* ]]; then pecl install -f memcached-2.1.0; fi;
     - if [[ $TRAVIS_PHP_VERSION != hhvm ]]; then echo extension = ldap.so >> $INI_FILE; fi;
+    - if [[ $TRAVIS_PHP_VERSION != hhvm ]]; then echo extension = redis.so >> $INI_FILE; fi;
     - if [[ $TRAVIS_PHP_VERSION != hhvm ]]; then phpenv config-rm xdebug.ini; fi;
     - if [[ $deps != skip ]]; then composer self-update; fi;
     - if [[ $deps != skip && $TRAVIS_REPO_SLUG = symfony/symfony ]]; then cp .composer/* ~/.composer/; composer global install --prefer-dist; fi;

src/Symfony/Component/Cache/Adapter/RedisAdapter.php

@@ -0,0 +1,115 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Cache\Adapter;
+
+use Symfony\Component\Cache\Exception\InvalidArgumentException;
+
+/**
+ * @author Aurimas Niekis <aurimas@niekis.lt>
+ */
+class RedisAdapter extends AbstractAdapter
+{
+    private $redis;
+
+    public function __construct(\Redis $redisConnection, $namespace = '', $defaultLifetime = 0)
+    {
+        $this->redis = $redisConnection;
+
+        if (preg_match('#[^-+_.A-Za-z0-9]#', $namespace, $match)) {
+            throw new InvalidArgumentException(sprintf('RedisAdapter namespace contains "%s" but only characters in [-+_.A-Za-z0-9] are allowed.', $match[0]));
+        }
+
+        parent::__construct($namespace, $defaultLifetime);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doFetch(array $ids)
+    {
+        $values = $this->redis->mget($ids);
+        $index = 0;
+        $result = [];
+
+        foreach ($ids as $id) {
+            if (false !== $value = $values[$index++]) {
+                $result[$id] = unserialize($value);
+            }
+        }
+
+        return $result;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doHave($id)
+    {
+        return $this->redis->exists($id);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doClear($namespace)
+    {
+        if (!isset($namespace[0])) {
+            $this->redis->flushDB();
+        } else {
+            // As documented in Redis documentation (http://redis.io/commands/keys) using KEYS
+            // can hang your server when it is executed against large databases (millions of items).
+            // Whenever you hit this scale, it is advised to deploy one Redis database per cache pool
+            // instead of using namespaces, so that the above FLUSHDB is used instead.
+            $this->redis->eval(sprintf("local keys=redis.call('KEYS','%s*') for i=1,#keys,5000 do redis.call('DEL',unpack(keys,i,math.min(i+4999,#keys))) end", $namespace));
+        }
+
+        return true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doDelete(array $ids)
+    {
+        $this->redis->del($ids);
+
+        return true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function doSave(array $values, $lifetime)
+    {
+        $failed = array();
+
+        foreach ($values as $id => $v) {
+            try {
+                $values[$id] = serialize($v);
+            } catch (\Exception $e) {
+                $failed[] = $id;
+            }
+        }
+
+        if (!$this->redis->mSet($values)) {
+            return false;
+        }
+
+        if ($lifetime >= 1) {
+            foreach ($values as $id => $v) {
+                $this->redis->expire($id, $lifetime);
+            }
+        }
+
+        return $failed;
+    }
+}

src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php

@@ -0,0 +1,45 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Cache\Tests\Adapter;
+
+use Cache\IntegrationTests\CachePoolTest;
+use Symfony\Component\Cache\Adapter\RedisAdapter;
+
+/**
+ * @requires extension redis
+ */
+class RedisAdapterTest extends CachePoolTest
+{
+    private static $redis;
+
+    public function createCachePool()
+    {
+        if (defined('HHVM_VERSION')) {
+            $this->skippedTests['testDeferredSaveWithoutCommit'] = 'Fails on HHVM';
+        }
+
+        return new RedisAdapter(self::$redis, str_replace('\\', '.', __CLASS__));
+    }
+
+    public static function setupBeforeClass()
+    {
+        self::$redis = new \Redis();
+        self::$redis->connect('127.0.0.1');
+        self::$redis->select(1993);
+    }
+
+    public static function tearDownAfterClass()
+    {
+        self::$redis->flushDB();
+        self::$redis->close();
+    }
+}