From: Michael Wallner <mike@php.net>
Date: Wed, 26 Nov 2014 16:23:57 +0000 (+0100)
Subject: dont depend on react
X-Git-Tag: v2.1.0~1^2~2
X-Git-Url: https://git.m6w6.name/?p=m6w6%2Fpq-gateway;a=commitdiff_plain;h=b739919b7b67e746792a48ef58653e6951de7db1

dont depend on react
---

diff --git a/lib/pq/Query/AsyncExecutor.php b/lib/pq/Query/AsyncExecutor.php
index 737c0eb..e7c1c35 100644
--- a/lib/pq/Query/AsyncExecutor.php
+++ b/lib/pq/Query/AsyncExecutor.php
@@ -5,34 +5,138 @@ namespace pq\Query\Executor;
 use \pq\Query\Executor;
 use \pq\Query\WriterInterface;
 
-/**
- * @requires \React\Promise
- */
-use \React\Promise\Deferred;
-
 /**
  * An asynchronous query executor
  */
-class Async extends Executor
+class AsyncExecutor extends Executor
 {
+	/**
+	 * Context initializer
+	 * @var callable
+	 */
+	protected $init;
+	
+	/**
+	 * Result resolver
+	 * @var callable
+	 */
+	protected $done;
+	
+	/**
+	 * Callback queue
+	 * @var callable
+	 */
+	protected $then;
+	
+	/**
+	 * Set (promise) callbacks
+	 * 
+	 * Example with reactphp:
+	 * <code>
+	 * use \React\Promise\Deferred;
+	 * 
+	 * $exec = new pq\Query\AsyncExecutor(new pq\Connection);
+	 * $exec->setCallbacks(
+	 * # init context
+	 * function() {
+	 *		return new Deferred;
+	 * },
+	 * # done
+	 * function(Deferred $context, $result) {
+	 *		$context->resolver()->resolve($result);
+	 * },
+	 * # then
+	 * function(Deferred $context, callable $cb) {
+	 *		return $context->then($cb);
+	 * });
+	 * $exec->execute($queryWriter, function($result){});
+	 * </code>
+	 * 
+	 * Example with amphp:
+	 * <code>
+	 * use amp\Future;
+	 * use function amp\reactor;
+	 * 
+	 * $exec = new pq\Query\AsyncExecutor(new pq\Connection);
+	 * $exec->setCallbacks(
+	 * # init context
+	 * function() {
+	 *		return new Future(reactor());
+	 * },
+	 * # done
+	 * function(Future $context, $result) {
+	 *		$context->succeed($result);
+	 * },
+	 * # then
+	 * function(Future $context, callable $cb) {
+	 *		return $context->when(function ($error, $result) {
+	 *			$cb($result);
+	 *		});
+	 * });
+	 * $exec->execute($queryWriter, function($result){});
+	 * </code>
+	 * 
+	 * @param callable $init context initializer as function()
+	 * @param callable $done result receiver as function($context, $result)
+	 * @param callable $then callback queue as function($context, $callback)
+	 */
+	function setCallbacks(callable $init, callable $done, callable $then) {
+		$this->init = $init;
+		$this->done = $done;
+		$this->then = $then;
+	}
+	
+	/**
+	 * Get (promise) callbacks previously set
+	 * @return array(callable)
+	 */
+	function getCallbacks() {
+		return array($this->init, $this->done, $this->then);
+	}
+	
+	/**
+	 * Prepare (promise) callbacks
+	 * @param callable $callback
+	 * @return array($context, $resolver)
+	 */
+	protected function prepareCallback(callable $callback/*, ... */) {
+		list($init, $done, $then) = $this->getCallbacks();
+		
+		$context = $init();
+		foreach (func_get_args() as $cb) {
+			$then($context, $cb);
+		}
+		$then($context, $callback);
+		
+		return array($context, function($result) use ($context, $done) {
+			$done($context, $result);
+		});
+	}
+	
+	/**
+	 * Result callback
+	 * @param \pq\Result $result
+	 */
+	protected function receiveResult(\pq\Result $result) {
+		$this->result = $result;
+		$this->notify();
+	}
+	
 	/**
 	 * Execute the query asynchronously through \pq\Connection::execParamsAsync()
 	 * @param \pq\Query\WriterInterface $query
-	 * @param callable $callback
-	 * @return \React\Promise\DeferredPromise
+	 * @param callable $callback result callback
+	 * @return mixed context created by the init callback
 	 */
 	function execute(WriterInterface $query, callable $callback) {
 		$this->result = null;
 		$this->query = $query;
 		$this->notify();
 		
-		$deferred = new Deferred;
-		$this->getConnection()->execParamsAsync($query, $query->getParams(), $query->getTypes(), 
-			array($deferred->resolver(), "resolve"));
-		
-		return $deferred->then(function($result) {
-			$this->result = $result;
-			$this->notify();
-		})->then($callback);
+		list($context, $resolver) = $this->prepareCallback(
+			array($this, "receiveResult"), $callback);
+		$this->getConnection()->execParamsAsync($query, $query->getParams(), 
+			$query->getTypes(), $resolver);
+		return $context;
 	}
 }