Cache: added events WIP

Author: dg

src/Caching/Cache.php

@@ -33,9 +33,18 @@ class Cache
 		NAMESPACES = 'namespaces',
 		ALL = 'all';
 
+	public const
+		EVENT_HIT = 'hit',
+		EVENT_MISS = 'miss',
+		EVENT_SAVE = 'save',
+		EVENT_REMOVE = 'remove';
+
 	/** @internal */
 	public const NAMESPACE_SEPARATOR = "\x00";
 
+	/** @var array */
+	public $onEvent;
+
 	/** @var Storage */
 	private $storage;
 
@@ -88,8 +97,9 @@ public function load($key, callable $generator = null)
 	{
 		$storageKey = $this->generateKey($key);
 		$data = $this->storage->read($storageKey);
+		$this->onEvent($this, $data === null ? self::EVENT_MISS : self::EVENT_HIT, $key);
 		if ($data === null && $generator) {
-			$this->storage->lock($storageKey);			
+			$this->storage->lock($storageKey);
 			try {
 				$data = $generator(...[&$dependencies]);
 			} catch (\Throwable $e) {
@@ -134,12 +144,14 @@ public function bulkLoad(array $keys, callable $generator = null): array
 		foreach ($keys as $i => $key) {
 			$storageKey = $storageKeys[$i];
 			if (isset($cacheData[$storageKey])) {
+				$this->onEvent($this, self::EVENT_HIT, $key);
 				$result[$key] = $cacheData[$storageKey];
 			} elseif ($generator) {
 				$result[$key] = $this->load($key, function (&$dependencies) use ($key, $generator) {
 					return $generator(...[$key, &$dependencies]);
 				});
 			} else {
+				$this->onEvent($this, self::EVENT_MISS, $key);
 				$result[$key] = null;
 			}
 		}
@@ -165,27 +177,30 @@ public function bulkLoad(array $keys, callable $generator = null): array
 	 */
 	public function save($key, $data, array $dependencies = null)
 	{
-		$key = $this->generateKey($key);
+		$storageKey = $this->generateKey($key);
 
 		if ($data instanceof \Closure) {
 			trigger_error(__METHOD__ . '() closure argument is deprecated.', E_USER_WARNING);
-			$this->storage->lock($key);
+			$this->storage->lock($storageKey);
 			try {
 				$data = $data(...[&$dependencies]);
 			} catch (\Throwable $e) {
-				$this->storage->remove($key);
+				$this->storage->remove($storageKey);
 				throw $e;
 			}
 		}
 
 		if ($data === null) {
-			$this->storage->remove($key);
+			$this->storage->remove($storageKey);
+			$this->onEvent($this, self::EVENT_REMOVE, $key);
 		} else {
 			$dependencies = $this->completeDependencies($dependencies);
 			if (isset($dependencies[self::EXPIRATION]) && $dependencies[self::EXPIRATION] <= 0) {
-				$this->storage->remove($key);
+				$this->storage->remove($storageKey);
+				$this->onEvent($this, self::EVENT_REMOVE, $key);
 			} else {
-				$this->storage->write($key, $data, $dependencies);
+				$this->storage->write($storageKey, $data, $dependencies);
+				$this->onEvent($this, self::EVENT_SAVE, $key);
 			}
 			return $data;
 		}

tests/Caching/Cache.bulkLoad.phpt

@@ -18,30 +18,54 @@ require __DIR__ . '/Cache.php';
 test(function () {
 	$storage = new TestStorage;
 	$cache = new Cache($storage, 'ns');
+	$cache->onEvent[] = function (...$args) use (&$event) {
+		$event[] = $args;
+	};
+
 	Assert::same([1 => null, 2 => null], $cache->bulkLoad([1, 2]), 'data');
+	Assert::same([[$cache, $cache::EVENT_MISS, 1], [$cache, $cache::EVENT_MISS, 2]], $event);
 
+	$event = [];
 	Assert::same([1 => 1, 2 => 2], $cache->bulkLoad([1, 2], function ($key) {
 		return $key;
 	}));
+	Assert::same([
+		[$cache, $cache::EVENT_MISS, 1], [$cache, $cache::EVENT_SAVE, 1],
+		[$cache, $cache::EVENT_MISS, 2], [$cache, $cache::EVENT_SAVE, 2],
+	], $event);
 
+	$event = [];
 	$data = $cache->bulkLoad([1, 2]);
 	Assert::same(1, $data[1]['data']);
 	Assert::same(2, $data[2]['data']);
+	Assert::same([[$cache, $cache::EVENT_HIT, 1], [$cache, $cache::EVENT_HIT, 2]], $event);
 });
 
 // storage with bulk load support
 test(function () {
 	$storage = new BulkReadTestStorage;
 	$cache = new Cache($storage, 'ns');
+	$cache->onEvent[] = function (...$args) use (&$event) {
+		$event[] = $args;
+	};
+
 	Assert::same([1 => null, 2 => null], $cache->bulkLoad([1, 2]));
+	Assert::same([[$cache, $cache::EVENT_MISS, 1], [$cache, $cache::EVENT_MISS, 2]], $event);
 
+	$event = [];
 	Assert::same([1 => 1, 2 => 2], $cache->bulkLoad([1, 2], function ($key) {
 		return $key;
 	}));
+	Assert::same([
+		[$cache, $cache::EVENT_MISS, 1], [$cache, $cache::EVENT_SAVE, 1],
+		[$cache, $cache::EVENT_MISS, 2], [$cache, $cache::EVENT_SAVE, 2],
+	], $event);
 
+	$event = [];
 	$data = $cache->bulkLoad([1, 2]);
 	Assert::same(1, $data[1]['data']);
 	Assert::same(2, $data[2]['data']);
+	Assert::same([[$cache, $cache::EVENT_HIT, 1], [$cache, $cache::EVENT_HIT, 2]], $event);
 });
 
 // dependencies

tests/Caching/Cache.load.phpt

@@ -18,16 +18,25 @@ require __DIR__ . '/Cache.php';
 // load twice with fallback
 $storage = new TestStorage;
 $cache = new Cache($storage, 'ns');
+$cache->onEvent[] = function (...$args) use (&$event) {
+	$event[] = $args;
+};
 
 $value = $cache->load('key', function () {
 	return 'value';
 });
 Assert::same('value', $value);
+Assert::same([
+	[$cache, $cache::EVENT_MISS, 'key'],
+	[$cache, $cache::EVENT_SAVE, 'key'],
+], $event);
 
+$event = [];
 $data = $cache->load('key', function () {
 	return "won't load this value"; // will read from storage
 });
 Assert::same('value', $data['data']);
+Assert::same([[$cache, $cache::EVENT_HIT, 'key']], $event);
 
 
 // load twice with closure fallback, pass dependencies

tests/Caching/Cache.save.phpt

@@ -18,9 +18,13 @@ require __DIR__ . '/Cache.php';
 // save value with dependencies
 $storage = new testStorage;
 $cache = new Cache($storage, 'ns');
+$cache->onEvent[] = function (...$args) use (&$event) {
+	$event[] = $args;
+};
 $dependencies = [Cache::TAGS => ['tag']];
 
 $cache->save('key', 'value', $dependencies);
+Assert::same([[$cache, $cache::EVENT_SAVE, 'key']], $event);
 
 $res = $cache->load('key');
 Assert::same('value', $res['data']);