Merge pull request #4 from mcg-web/removed-all-event-references

Removed all eventLoop references
overblog · Nov 11, 2016 · 0c84e81 · 0c84e81
2 parents ba33d6f + c4dd048
commit 0c84e81
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Showing 8 changed files with 184 additions and 232 deletions.
diff --git a/.travis.yml b/.travis.yml
@@ -29,5 +29,4 @@ install: composer update --prefer-dist --no-interaction
 script: if [ "$TRAVIS_PHP_VERSION" == "5.6" ]; then phpunit -d xdebug.max_nesting_level=1000 --debug --coverage-clover build/logs/clover.xml; else phpunit --debug; fi
 
 after_success:
-    - composer require "satooshi/php-coveralls:^1.0"
-    - travis_retry php vendor/bin/coveralls -v
+    - if [ "$TRAVIS_PHP_VERSION" == "5.6" ]; then composer require "satooshi/php-coveralls:^1.0" && travis_retry php vendor/bin/coveralls -v; fi
diff --git a/README.md b/README.md
@@ -11,8 +11,7 @@ data sources such as databases or web services via batching and caching.
 
 ## Requirements
 
-* This library require [React/Promise](https://github.com/reactphp/promise) and PHP >= 5.5 to works.
-* The [React/EventLoop](https://github.com/reactphp/event-loop) component are **totally optional** (see `await` method for more details).
+This library require [React/Promise](https://github.com/reactphp/promise) and PHP >= 5.5 to works.
 
 ## Getting Started
 
@@ -33,15 +32,15 @@ use Overblog\DataLoader\DataLoader;
 
 $myBatchGetUsers = function ($keys) { /* ... */ };
 
-$userLoader = new DataLoader(new BatchLoadFn($myBatchGetUsers));
+$userLoader = new DataLoader($myBatchGetUsers);
 ```
 
-A batch loading instance accepts a callable callback that accepts an Array of keys, and returns a Promise which
+A batch loading callable / callback accepts an Array of keys, and returns a Promise which
 resolves to an Array of values.
 
 Then load individual values from the loader. DataLoaderPHP will coalesce all
-individual loads which occur within a single frame of execution (a single tick
-of the event loop if install or using `await` method) and then call your batch function with all requested keys.
+individual loads which occur within a single frame of execution (using `await` method) 
+and then call your batch function with all requested keys.
 
 ```php
 $userLoader->load(1)
@@ -80,7 +79,7 @@ your application:
 
 ```php
 $promise1A = $userLoader->load(1);
-$promise1B = userLoader->load(1);
+$promise1B = $userLoader->load(1);
 var_dump($promise1A === $promise1B); // bool(true)
 ```
 
@@ -94,7 +93,7 @@ Here's a simple example using SQL UPDATE to illustrate.
 ```php
 $sql = 'UPDATE users WHERE id=4 SET username="zuck"';
 if (true === $conn->query($sql)) {
-    $userLoader->clear(4);
+  $userLoader->clear(4);
 }
 ```
 
@@ -123,12 +122,11 @@ Each `DataLoaderPHP` instance contains a unique memoized cache. Use caution when
 used in long-lived applications or those which serve many users with different
 access permissions and consider creating a new instance per web request.
 
-##### `new DataLoader(batchLoadFn $batchLoadFn [, Option $options])`
+##### `new DataLoader(callable $batchLoadFn [, Option $options])`
 
 Create a new `DataLoaderPHP` given a batch loading instance and options.
 
-- *$batchLoadFn*: A object which accepts a callable callback that accepts an Array of keys,
-    and returns a Promise which resolves to an Array of values.
+- *$batchLoadFn*: A callable / callback which accepts an Array of keys, and returns a Promise which resolves to an Array of values.
 - *$options*: An optional object of options:
 
   - *batch*: Default `true`. Set to `false` to disable batching, instead
@@ -164,7 +162,7 @@ list($a, $b) = DataLoader::await($myLoader->loadMany(['a', 'b']);
 This is equivalent to the more verbose:
 
 ```js
-list($a, $b) = await DataLoader::await(\React\Promise\all([
+list($a, $b) = DataLoader::await(\React\Promise\all([
   $myLoader->load('a'),
   $myLoader->load('b')
 ]);

diff --git a/src/BatchLoadFn.php b/src/BatchLoadFn.php
diff --git a/src/DataLoader.php b/src/DataLoader.php
@@ -16,7 +16,7 @@
 class DataLoader
 {
     /**
-     * @var BatchLoadFn
+     * @var callable
      */
     private $batchLoadFn;
 
@@ -35,26 +35,15 @@ class DataLoader
      */
     private $queue = [];
 
-    /**
-     * @var null|\React\EventLoop\LoopInterface
-     */
-    private $eventLoop;
-
-    /**
-     * @var Promise
-     */
-    private $resolvedPromise;
-
     /**
      * @var self[]
      */
     private static $instances = [];
 
-    public function __construct(BatchLoadFn $batchLoadFn, Option $options = null)
+    public function __construct(callable $batchLoadFn, Option $options = null)
     {
         $this->batchLoadFn = $batchLoadFn;
         $this->options = $options ?: new Option();
-        $this->eventLoop = class_exists('React\\EventLoop\\Factory') ? \React\EventLoop\Factory::create() : null;
         $this->promiseCache = $this->options->getCacheMap();
         self::$instances[] = $this;
     }
@@ -97,12 +86,7 @@ function ($resolve, $reject) use (&$promise, $key, $shouldBatch) {
                 // A single dispatch should be scheduled per queue at the time when the
                 // queue changes from "empty" to "full".
                 if (count($this->queue) === 1) {
-                    if ($shouldBatch) {
-                        // If batching, schedule a task to dispatch the queue.
-                        $this->enqueuePostPromiseJob(function () {
-                            $this->dispatchQueue();
-                        });
-                    } else {
+                    if (!$shouldBatch) {
                         // Otherwise dispatch the (queue of one) immediately.
                         $this->dispatchQueue();
                     }
@@ -124,11 +108,11 @@ function (callable $resolve, callable $reject) {
     /**
      * Loads multiple keys, promising an array of values:
      *
-     *     [$a, $b] = $myLoader->loadMany(['a', 'b']);
+     *     list($a, $b) = $myLoader->loadMany(['a', 'b']);
      *
      * This is equivalent to the more verbose:
      *
-     *     [$a, $b] = \React\Promise\all([
+     *     list($a, $b) = \React\Promise\all([
      *       $myLoader->load('a'),
      *       $myLoader->load('b')
      *     ]);
@@ -139,7 +123,7 @@ function (callable $resolve, callable $reject) {
     public function loadMany($keys)
     {
         if (!is_array($keys) && !$keys instanceof \Traversable) {
-            throw new \InvalidArgumentException(sprintf('The %s function must be called with Array<key> but got: %s.', __METHOD__, gettype($keys)));
+            throw new \InvalidArgumentException(sprintf('The "%s" method must be called with Array<key> but got: %s.', __METHOD__, gettype($keys)));
         }
         return \React\Promise\all(array_map(
             function ($key) {
@@ -207,7 +191,9 @@ public function __destruct()
         if ($this->needProcess()) {
             foreach ($this->queue as $data) {
                 try {
-                    $data['promise']->cancel();
+                    /** @var Promise $promise */
+                    $promise = $data['promise'];
+                    $promise->cancel();
                 } catch (\Exception $e) {
                     // no need to do nothing if cancel failed
                 }
@@ -243,51 +229,45 @@ public static function await($promise = null, $unwrap = true)
     {
         self::awaitInstances();
 
-        if (null !== $promise) {
-            $resolvedValue = null;
-            $exception = null;
+        if (null === $promise) {
+            return null;
+        }
+        $resolvedValue = null;
+        $exception = null;
 
-            if (!is_callable([$promise, 'then'])) {
-                throw new \InvalidArgumentException('Promise must have a "then" method.');
-            }
+        if (!is_callable([$promise, 'then'])) {
+            throw new \InvalidArgumentException(sprintf('The "%s" method must be called with a Promise ("then" method).', __METHOD__));
+        }
 
-            $promise->then(function ($values) use (&$resolvedValue) {
-                $resolvedValue = $values;
-            }, function ($reason) use (&$exception) {
-                $exception = $reason;
-            });
-            if ($exception instanceof \Exception) {
-                if (!$unwrap) {
-                    return $exception;
-                }
-                throw $exception;
+        $promise->then(function ($values) use (&$resolvedValue) {
+            $resolvedValue = $values;
+        }, function ($reason) use (&$exception) {
+            $exception = $reason;
+        });
+        if ($exception instanceof \Exception) {
+            if (!$unwrap) {
+                return $exception;
             }
-
-            return $resolvedValue;
+            throw $exception;
         }
+
+        return $resolvedValue;
     }
 
     private static function awaitInstances()
     {
         $dataLoaders = self::$instances;
-        if (empty($dataLoaders)) {
-            return;
-        }
+        if (!empty($dataLoaders)) {
+            $wait = true;
 
-        $wait = true;
-
-        while ($wait) {
-            foreach ($dataLoaders as $dataLoader) {
-                try {
+            while ($wait) {
+                foreach ($dataLoaders as $dataLoader) {
                     if (!$dataLoader || !$dataLoader->needProcess()) {
                         $wait = false;
                         continue;
                     }
                     $wait = true;
                     $dataLoader->process();
-                } catch (\Exception $e) {
-                    $wait = false;
-                    continue;
                 }
             }
         }
@@ -305,27 +285,11 @@ private function checkKey($key, $method)
     {
         if (null === $key) {
             throw new \InvalidArgumentException(
-                sprintf('The %s function must be called with a value, but got: %s.', $method, gettype($key))
+                sprintf('The "%s" method must be called with a value, but got: %s.', $method, gettype($key))
             );
         }
     }
 
-    /**
-     * @param $fn
-     */
-    private function enqueuePostPromiseJob($fn)
-    {
-        if (!$this->resolvedPromise) {
-            $this->resolvedPromise = \React\Promise\resolve();
-        }
-
-        if ($this->eventLoop) {
-            $this->resolvedPromise->then(function () use ($fn) {
-                $this->eventLoop->nextTick($fn);
-            });
-        }
-    }
-
     /**
      * Given the current state of a Loader instance, perform a batch load
      * from its current queue.