Thread safe add() for Cache Repository for the MemcachedStore

src/Illuminate/Cache/MemcachedStore.php

@@ -1,8 +1,9 @@
 <?php namespace Illuminate\Cache;
 
 use Illuminate\Contracts\Cache\Store;
+use Illuminate\Contracts\Cache\ThreadSafeStore;
 
-class MemcachedStore extends TaggableStore implements Store {
+class MemcachedStore extends TaggableStore implements ThreadSafeStore {
 
 	/**
 	 * The Memcached instance.
@@ -60,6 +61,19 @@ public function put($key, $value, $minutes)
 		$this->memcached->set($this->prefix.$key, $value, $minutes * 60);
 	}
 
+	/**
+	 * Store an item in the cache if the key does not exist for a given number of minutes.
+	 *
+	 * @param  string  $key
+	 * @param  mixed   $value
+	 * @param  int     $minutes
+	 * @return bool
+	 */
+	public function add($key, $value, $minutes)
+	{
+		return $this->memcached->add($this->prefix.$key, $value, $minutes * 60);
+	}
+
 	/**
 	 * Increment the value of an item in the cache.
 	 *

src/Illuminate/Cache/Repository.php

@@ -5,6 +5,7 @@
 use ArrayAccess;
 use Carbon\Carbon;
 use Illuminate\Contracts\Cache\Store;
+use Illuminate\Contracts\Cache\ThreadSafeStore;
 use Illuminate\Support\Traits\Macroable;
 use Illuminate\Contracts\Events\Dispatcher;
 use Illuminate\Contracts\Cache\Repository as CacheContract;
@@ -18,7 +19,7 @@ class Repository implements CacheContract, ArrayAccess {
 	/**
 	 * The cache store implementation.
 	 *
-	 * @var \Illuminate\Contracts\Cache\Store
+	 * @var \Illuminate\Contracts\Cache\Store|\Illuminate\Contracts\Cache\ThreadSafeStore
 	 */
 	protected $store;
 
@@ -36,6 +37,13 @@ class Repository implements CacheContract, ArrayAccess {
 	 */
 	protected $default = 60;
 
+	/**
+	 * Whether or not the cache store implements the \Illuminate\Contracts\Cache\ThreadSafeStore interface
+	 *
+	 * @var bool
+	 */
+	protected $isStoreThreadSafe = false;
+
 	/**
 	 * Create a new cache repository instance.
 	 *
@@ -44,6 +52,11 @@ class Repository implements CacheContract, ArrayAccess {
 	public function __construct(Store $store)
 	{
 		$this->store = $store;
+		if ($store instanceof ThreadSafeStore)
+		{
+			$this->isStoreThreadSafe = true;
+		}
+
 	}
 
 	/**
@@ -154,6 +167,11 @@ public function put($key, $value, $minutes)
 	 */
 	public function add($key, $value, $minutes)
 	{
+		if ($this->isStoreThreadSafe)
+		{
+			return $this->store->add($key, $value, $minutes);
+		}
+
 		if (is_null($this->get($key)))
 		{
 			$this->put($key, $value, $minutes); return true;

src/Illuminate/Contracts/Cache/ThreadSafeStore.php

@@ -0,0 +1,15 @@
+<?php namespace Illuminate\Contracts\Cache;
+
+interface ThreadSafeStore extends Store {
+
+	/**
+	 * Store an item in the cache if the key does not exist for a given number of minutes.
+	 *
+	 * @param  string  $key
+	 * @param  mixed   $value
+	 * @param  int     $minutes
+	 * @return bool
+	 */
+	public function add($key, $value, $minutes);
+
+}