Add ConnectionManagerConcurrent

Author: clue

README.md

@@ -86,6 +86,11 @@ any of the given `ConnectionManager`s in consecutive order until the first one s
 The `ConnectionManagerRandom($connectors)` works much like `ConnectionManagerConsecutive` but instead
 of using a fixed order, it always uses a randomly shuffled order.
 
+### Concurrent
+
+The `ConnectionManagerConcurrent($connectors)` establishes connections by trying to connect through
+ALL of the given `ConnectionManager`s at once, until the first one succeeds.
+
 ### Selective
 
 The `ConnectionManagerSelective()` manages several `Connector`s and forwards connection through either of

src/Multiple/ConnectionManagerConcurrent.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace ConnectionManager\Extra\Multiple;
+
+use ConnectionManager\Extra\Multiple\ConnectionManagerConsecutive;
+use React\Promise;
+use React\Promise\CancellablePromiseInterface;
+
+class ConnectionManagerConcurrent extends ConnectionManagerConsecutive
+{
+    public function create($host, $port)
+    {
+        $all = array();
+        foreach ($this->managers as $connector) {
+            /* @var $connection Connector */
+            $all []= $connector->create($host, $port);
+        }
+        return Promise\any($all)->then(function ($conn) use ($all) {
+            // a connection attempt succeeded
+            // => cancel all pending connection attempts
+            foreach ($all as $promise) {
+                if ($promise instanceof CancellablePromiseInterface) {
+                    $promise->cancel();
+                }
+
+                // if promise resolves despite cancellation, immediately close stream
+                $promise->then(function ($stream) use ($conn) {
+                    if ($stream !== $conn) {
+                        $stream->close();
+                    }
+                });
+            }
+            return $conn;
+        });
+    }
+}

tests/Multiple/ConnectionManagerConcurrentTest.php

@@ -0,0 +1,70 @@
+<?php
+
+use ConnectionManager\Extra\Multiple\ConnectionManagerConcurrent;
+use React\Promise;
+
+class ConnectionManagerConcurrentTest extends TestCase
+{
+    public function testEmptyRejects()
+    {
+        $connector = new ConnectionManagerConcurrent();
+
+        $promise = $connector->create('google.com', 80);
+
+        $this->assertPromiseReject($promise);
+    }
+
+    public function testWillForwardToInnerConnector()
+    {
+        $pending = new Promise\Promise(function() { });
+
+        $only = $this->getMock('React\SocketClient\ConnectorInterface');
+        $only->expects($this->once())->method('create')->with('google.com', 80)->willReturn($pending);
+
+        $connector = new ConnectionManagerConcurrent();
+        $connector->addConnectionManager($only);
+
+        $promise = $connector->create('google.com', 80);
+
+        $promise->then($this->expectCallableNever(), $this->expectCallableNever());
+    }
+
+    public function testWillCancelOtherIfOneResolves()
+    {
+        $resolved = Promise\resolve($this->getMock('React\Stream\DuplexStreamInterface'));
+        $first = $this->getMock('React\SocketClient\ConnectorInterface');
+        $first->expects($this->once())->method('create')->with('google.com', 80)->willReturn($resolved);
+
+        $pending = new Promise\Promise(function() { }, $this->expectCallableOnce());
+        $second = $this->getMock('React\SocketClient\ConnectorInterface');
+        $second->expects($this->once())->method('create')->with('google.com', 80)->willReturn($pending);
+
+        $connector = new ConnectionManagerConcurrent();
+        $connector->addConnectionManager($first);
+        $connector->addConnectionManager($second);
+
+        $promise = $connector->create('google.com', 80);
+
+        $this->assertPromiseResolve($promise);
+    }
+
+    public function testWillCloseOtherIfOneResolves()
+    {
+        $resolved = Promise\resolve($this->getMock('React\Stream\DuplexStreamInterface'));
+        $first = $this->getMock('React\SocketClient\ConnectorInterface');
+        $first->expects($this->once())->method('create')->with('google.com', 80)->willReturn($resolved);
+
+        $slower = $this->getMock('React\Stream\DuplexStreamInterface');
+        $slower->expects($this->once())->method('close');
+        $second = $this->getMock('React\SocketClient\ConnectorInterface');
+        $second->expects($this->once())->method('create')->with('google.com', 80)->willReturn(Promise\resolve($slower));
+
+        $connector = new ConnectionManagerConcurrent();
+        $connector->addConnectionManager($first);
+        $connector->addConnectionManager($second);
+
+        $promise = $connector->create('google.com', 80);
+
+        $this->assertPromiseResolve($promise);
+    }
+}