Merge pull request #14 from php-cache/callable

Using callable

Author: cryptiklemur

src/AbstractCachePool.php

@@ -61,20 +61,19 @@ protected function getItemWithoutGenerateCacheKey($key)
             return is_object($item) ? clone $item : $item;
         }
 
-        $item = $this->fetchObjectFromCache($key);
-        if (false === $item || !$item instanceof CacheItemInterface) {
-            $item = new CacheItem($key);
-        }
+        $func = function () use ($key) {
+            return $this->fetchObjectFromCache($key);
+        };
 
-        return $item;
+        return new CacheItem($key, $func);
     }
 
     /**
      * Fetch an object from the cache implementation.
      *
      * @param string $key
      *
-     * @return CacheItem|false
+     * @return array with [isHit, value]
      */
     abstract protected function fetchObjectFromCache($key);
 
@@ -168,11 +167,6 @@ abstract protected function clearOneObjectFromCache($key);
      */
     public function save(CacheItemInterface $item)
     {
-        // This item has no data
-        if (!$item->isHit()) {
-            return false;
-        }
-
         if ($item instanceof TaggableItemInterface) {
             $key = $item->getTaggedKey();
         } else {

src/CacheItem.php

@@ -23,6 +23,11 @@ class CacheItem implements HasExpirationDateInterface, CacheItemInterface, Tagga
 {
     use TaggableItemTrait;
 
+    /**
+     * @type \Closure
+     */
+    private $callable;
+
     /**
      * @type string
      */
@@ -44,20 +49,20 @@ class CacheItem implements HasExpirationDateInterface, CacheItemInterface, Tagga
     private $hasValue = false;
 
     /**
-     * @param string                  $key
-     * @param bool                    $hasValue
-     * @param mixed                   $value
-     * @param \DateTimeInterface|null $expirationDate
+     * @param string        $key
+     * @param \Closure|bool $callable or boolean hasValue
      */
-    public function __construct($key, $hasValue = false, $value = null, \DateTimeInterface $expirationDate = null)
+    public function __construct($key, $callable = null, $value = null)
     {
-        $this->taggedKey      = $key;
-        $this->key            = $this->getKeyFromTaggedKey($key);
-        $this->hasValue       = $hasValue;
-        $this->expirationDate = $expirationDate;
-
-        if ($hasValue) {
-            $this->value = $value;
+        $this->taggedKey = $key;
+        $this->key       = $this->getKeyFromTaggedKey($key);
+
+        if ($callable === true) {
+            $this->hasValue = true;
+            $this->value    = $value;
+        } elseif ($callable !== false) {
+            // This must be a callable or null
+            $this->callable = $callable;
         }
     }
 
@@ -76,6 +81,7 @@ public function set($value)
     {
         $this->value    = $value;
         $this->hasValue = true;
+        $this->callable = null;
 
         return $this;
     }
@@ -97,15 +103,18 @@ public function get()
      */
     public function isHit()
     {
-        if (!$this->hasValue) {
-            return false;
+        if ($this->callable !== null) {
+            // Initialize
+            $f                                  = $this->callable;
+            list($this->hasValue, $this->value) = $f();
+            $this->callable                     = null;
         }
 
-        if ($this->expirationDate === null) {
-            return true;
+        if (!$this->hasValue) {
+            return false;
         }
 
-        return (new \DateTime()) <= $this->expirationDate;
+        return true;
     }
 
     /**
@@ -121,7 +130,11 @@ public function getExpirationDate()
      */
     public function expiresAt($expiration)
     {
-        $this->expirationDate = $expiration;
+        if ($expiration instanceof \DateTimeInterface) {
+            $this->expirationDate = clone $expiration;
+        } else {
+            $this->expirationDate = $expiration;
+        }
 
         return $this;
     }

tests/CacheItemTest.php

@@ -60,18 +60,22 @@ public function testGet()
 
     public function testHit()
     {
-        $item = new CacheItem('test_key');
-        $this->assertFalse($item->isHit());
-
-        $item->set('foobar');
+        $item = new CacheItem('test_key', true, 'value');
         $this->assertTrue($item->isHit());
 
-        $item->set(null);
-        $this->assertTrue($item->isHit());
+        $item = new CacheItem('test_key', false, 'value');
+        $this->assertFalse($item->isHit());
 
-        $item->expiresAfter(5);
+        $closure = function () {
+            return [true, 'value'];
+        };
+        $item = new CacheItem('test_key', $closure);
         $this->assertTrue($item->isHit());
-        $item->expiresAfter(-1);
+
+        $closure = function () {
+            return [false, null];
+        };
+        $item = new CacheItem('test_key', $closure);
         $this->assertFalse($item->isHit());
     }