add gzip encode

Protocols/Http.php

@@ -161,7 +161,9 @@ class Http
                     break;
             }
         }
-
+		if(isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE){
+			HttpCache::$gzip = true;
+		}
         // Parse $_POST.
         if ($_SERVER['REQUEST_METHOD'] === 'POST') {
             if (isset($_SERVER['CONTENT_TYPE'])) {
@@ -249,7 +251,10 @@ class Http
                 $header .= $item . "\r\n";
             }
         }
-
+		if(HttpCache::$gzip && isset($connection->gzip) && $connection->gzip){
+			$header .= "Content-Encoding: gzip\r\n";
+			$content = gzencode($content,$connection->gzip);
+		}
         // header
         $header .= "Server: workerman/" . Worker::VERSION . "\r\nContent-Length: " . strlen($content) . "\r\n\r\n";
 
@@ -650,6 +655,7 @@ class HttpCache
      */
     public static $instance             = null;
     public static $header               = array();
+    public static $gzip                 = false;
     public static $sessionPath          = '';
     public static $sessionName          = '';
     public static $sessionGcProbability = 1;