Serialize Elements through PortSync

client/dart.js

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // Bootstrap support for Dart scripts on the page as this script.
 if (navigator.webkitStartDart) {
   if (!navigator.webkitStartDart()) {
     document.body.innerHTML = 'This build has expired.  Please download a new Dartium at http://www.dartlang.org/dartium/index.html';
   }
 } else {
@@ skipping 70 matching lines @@
           }
           return [ 'list', id, values ];
         });
       } else if (message instanceof LocalSendPortSync) {
         return [ 'sendport', 'nativejs', message.receivePort.id ];
       } else if (message instanceof DartSendPortSync) {
         return [ 'sendport', 'dart', message.isolateId, message.portId ];
       } else if (message instanceof Function) {
         return [ 'funcref', functionRefTable.makeRef(message),
                  doSerialize(functionRefTable.sendPort) ];
+      } else if (message instanceof HTMLElement) {
+        var id = elementId(message);
+        // Verify that the element is connected to the document.
+        // Otherwise, we will not be able to find it on the other side.
+        getElement(id);
+        return [ 'element', id ];
       } else if (message instanceof DartProxy) {
         return [ 'objref', message._id, doSerialize(message._port) ];
       } else if (message.__proto__ != {}.__proto__) {
         // TODO(vsm): Is the above portable and what we want?
         // Proxy non-map Objects.
         return [ 'objref', jsRefTable.makeRef(message),
                  doSerialize(jsRefTable.sendPort) ];
       } else {
         return checkedSerialization(message, function(id) {
           var keys = Object.getOwnPropertyNames(message);
@@ skipping 18 matching lines @@
         typeof(message) == 'number' ||
         typeof(message) == 'boolean') {
       return message;
     }
     switch (message[0]) {
       case 'map': return deserializeMap(message);
       case 'sendport': return deserializeSendPort(message);
       case 'list': return deserializeList(message);
       case 'funcref': return deserializeFunction(message);
       case 'objref': return deserializeProxy(message);
+      case 'element': return deserializeElement(message);
       default: throw 'unimplemented';
     }
   }
 
   function deserializeMap(message) {
     var result = { };
     var id = message[1];
     var keys = message[2];
     var values = message[3];
     for (var i = 0, length = keys.length; i < length; i++) {
@@ skipping 41 matching lines @@
     var id = message[1];
     var port = deserializeSendPort(message[2]);
     if (port instanceof LocalSendPortSync) {
       return jsRefTable.map[id];
     } else if (port instanceof DartSendPortSync) {
       return new DartProxy(port, id);
     }
     throw 'Illegal proxy object: ' + message;
   }
 
+  function deserializeElement(message) {
+    var id = message[1];
+    return getElement(id);
+  }
+
   window.registerPort = function(name, port) {
     var stringified = JSON.stringify(serialize(port));
     window.localStorage['dart-port:' + name] = stringified;
   };
 
   window.lookupPort = function(name) {
     var stringified = window.localStorage['dart-port:' + name];
     return deserialize(JSON.parse(stringified));
   };
 
@@ skipping 169 matching lines @@
     this._id = id;
   }
 
   // Leaking implementation.
   // TODO(vsm): provide proper, backend-specific implementation.
   function _makeFunctionFromRef(ref, sendPort) {
     return function() {
       return sendPort.callSync([ref, Array.prototype.slice.call(arguments)]);
     }
   }
+
+  var localNextElementId = 0;
+  var _DART_ID = 'data-dart_id';
+  
+  function elementId(e) {
+    if (e.hasAttribute(_DART_ID)) return e.getAttribute(_DART_ID);
+    var id = (localNextElementId++).toString();
+    e.setAttribute(_DART_ID, id);
+    return id;
+  }
+
+  function getElement(id) {
+    var list = document.querySelectorAll('[' + _DART_ID + '="' + id + '"]');
+
+    if (list.length > 1) throw 'Non unique ID: ' + id;
+    if (list.length == 0) {
+      throw 'Element must be attached to the document: ' + id;
+    }
+    return list[0];    
+  }
 })();