Added df_post() method for convenience to make post requests.

public-api.php

@@ -908,5 +908,26 @@ function df_write_json($data){
                     Dataface_Application::getInstance()->_conf['oe'].'"');
             echo json_encode($data);
         }
-
+
+        function df_post($url, $data=array(), $json=true) {
+
+            // use key 'http' even if you send the request to https://...
+            $options = array(
+                'http' => array(
+                    'header'  => "Content-type: application/x-www-form-urlencoded\r\n",
+                    'method'  => 'POST',
+                    'content' => http_build_query($data)
+                )
+            );
+            $context  = stream_context_create($options);
+            $result = file_get_contents($url, false, $context);
+            if ($result === FALSE) {
+                throw new Exception("HTTP request failed");
+            }
+            if ($json) {
+                return json_decode($result, true);
+            }
+            return $result;
+        }
+
 } // end if ( !defined( DATAFACE_PUBLIC_API_LOADED ) ){