Define additional TLS/SSL context options via withContext()

Author: clue

README.md

@@ -66,3 +66,15 @@ $secureConnector->create('www.google.com', 443)->then(function (React\Stream\Str
 
 $loop->run();
 ```
+
+The `withContext(array $context)` method can be used to return a
+new `SecureConnector` instance with the given
+[additional TLS/SSL context options](http://php.net/manual/en/context.ssl.php) applied.
+For example, this can be used to disable peer verification in a trusted network:
+ 
+```php
+$secureConnector->withContext(array(
+    'verify_peer' => false,
+    'verify_peer_name' => false,
+))->create('intranet.example.com', 443)->then($callback);
+```

src/SecureConnector.php

@@ -9,23 +9,45 @@ class SecureConnector implements ConnectorInterface
 {
     private $connector;
     private $streamEncryption;
+    private $context = array();
 
     public function __construct(ConnectorInterface $connector, LoopInterface $loop)
     {
         $this->connector = $connector;
         $this->streamEncryption = new StreamEncryption($loop);
     }
 
+    /**
+     * sets additional context options (for SSL context wrapper)
+     *
+     * @param array $sslContextOptions assosiative array of additional context options
+     * @return self returns a new instance with the additional context options applied
+     * @link http://php.net/manual/en/context.ssl.php
+     */
+    public function withContext(array $sslContextOptions)
+    {
+        $connector = clone $this;
+        $connector->context = array_filter($sslContextOptions + $connector->context, function ($value) {
+            return ($value !== null);
+        });
+
+        return $connector;
+    }
+
     public function create($host, $port)
     {
-        return $this->connector->create($host, $port)->then(function (Stream $stream) use ($host) {
+        // merge explicit context options with default context
+        $context = $this->context + array(
+            'SNI_enabled' => true,
+            'SNI_server_name' => $host,
+            'peer_name' => $host
+        );
+
+        return $this->connector->create($host, $port)->then(function (Stream $stream) use ($context) {
             // (unencrypted) TCP/IP connection succeeded
 
             // set required SSL/TLS context options
-            $resource = $stream->stream;
-            stream_context_set_option($resource, 'ssl', 'SNI_enabled', true);
-            stream_context_set_option($resource, 'ssl', 'SNI_server_name', $host);
-            stream_context_set_option($resource, 'ssl', 'peer_name', $host);
+            stream_context_set_option($stream->stream, array('ssl' => $context));
 
             // try to enable encryption
             return $this->streamEncryption->enable($stream)->then(null, function ($error) use ($stream) {