[RFC] Replace sendRequests with an async approach

src/HttpAsyncClient.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Http\Client;
+
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Sends a PSR-7 Request in an asynchronous way by returning a Promise.
+ *
+ * @author Joel Wurtz <joel.wurtz@gmail.com>
+ */
+interface HttpAsyncClient
+{
+    /**
+     * Sends a PSR-7 request in an asynchronous way.
+     *
+     * @param RequestInterface $request
+     *
+     * @return Promise
+     *
+     * @throws Exception
+     */
+    public function sendAsyncRequest(RequestInterface $request);
+}

src/HttpClient.php

@@ -2,12 +2,11 @@
 
 namespace Http\Client;
 
-use Http\Client\Exception\BatchException;
 use Psr\Http\Message\RequestInterface;
 use Psr\Http\Message\ResponseInterface;
 
 /**
- * Sends one or more PSR-7 Request and returns PSR-7 responses.
+ * Sends a PSR-7 Request and returns a PSR-7 response.
  *
  * @author GeLo <geloen.eric@gmail.com>
  * @author Márk Sági-Kazár <mark.sagikazar@gmail.com>
@@ -25,22 +24,4 @@ interface HttpClient
      * @throws Exception
      */
     public function sendRequest(RequestInterface $request);
-
-    /**
-     * Sends several PSR-7 requests.
-     *
-     * If the client is able to, these requests should be sent in parallel. Otherwise they will be sent sequentially.
-     * Either way, the caller may not rely on them being executed in any particular order.
-     *
-     * If one or more requests led to an exception, the BatchException is thrown. The BatchException gives access to the
-     * BatchResult that contains responses for successful calls and exceptions for unsuccessful calls.
-     *
-     * @param RequestInterface[] $requests
-     *
-     * @return BatchResult If all requests where successful.
-     *
-     * @throws Exception      On general setup problems.
-     * @throws BatchException If one or more requests led to exceptions.
-     */
-    public function sendRequests(array $requests);
 }

src/Promise.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace Http\Client;
+
+/**
+ * Promise represents a response that may not be available yet, but will be resolved at some point in future.
+ * It acts like a proxy to the actual response.
+ *
+ * @author Joel Wurtz <joel.wurtz@gmail.com>
+ */
+interface Promise
+{
+    /**
+     * Add behavior for when the promise is resolved or rejected (response will be available, or error happens)
+     *
+     * @param callable $onFulfilled Called when a response will be available, it will receive a Psr\Http\Message\RequestInterface object as the first argument
+     * @param callable $onRejected  Called when an error happens, it will receive a Http\Client\Exception object as the first argument
+     *
+     * @return Promise Always returns a new promise which is resolved with value of the executed callback (onFulfilled / onRejected)
+     */
+    public function then(callable $onFulfilled, callable $onRejected);
+}