add user-agent for php

composer.json

@@ -2,6 +2,7 @@
   "name": "grpc/grpc",
   "type": "library",
   "description": "gRPC library for PHP",
+  "version": "0.5.1",
   "keywords": ["rpc"],
   "homepage": "http://grpc.io",
   "license": "BSD-3-Clause",

src/php/composer.json

 {
   "name": "grpc/grpc",
   "description": "gRPC library for PHP",
-  "version": "0.5.0",
+  "version": "0.5.1",
   "homepage": "http://grpc.io",
   "license": "BSD-3-Clause",
   "repositories": [

src/php/lib/Grpc/BaseStub.php

@@ -60,7 +60,10 @@ class BaseStub {
       }
       unset($opts['update_metadata']);
     }
-         
+    $package_config = json_decode(
+        file_get_contents(dirname(__FILE__) . '/../../composer.json'), true);
+    $opts['grpc.primary_user_agent'] =
+        'grpc-php/' . $package_config['version'];
     $this->channel = new Channel($hostname, $opts);
   }