dart:developer service extension fixes

sdk/lib/developer/extension.dart

 // Copyright (c) 2015, 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.
 
 part of dart.developer;
 
 class ServiceExtensionResponse {
   final String _result;
   final int _errorCode;
   final String _errorDetail;
@@ skipping 10 matching lines @@
       : _result = null {
     _validateErrorCode(_errorCode);
     if (_errorDetail is! String) {
       throw new ArgumentError.value(_errorDetail,
                                     "errorDetail",
                                     "Must be a String");
     }
   }
 
   /// Invalid method parameter(s) error code.
-  static const kInvalidParams = -32602;
+  @deprecated static const kInvalidParams = invalidParams;
   /// Generic extension error code.
-  static const kExtensionError = -32000;
+  @deprecated static const kExtensionError = extensionError;
   /// Maximum extension provided error code.
-  static const kExtensionErrorMax = -32000;
+  @deprecated static const kExtensionErrorMax = extensionErrorMax;
   /// Minimum extension provided error code.
-  static const kExtensionErrorMin = -32016;
+  @deprecated static const kExtensionErrorMin = extensionErrorMin;
+
+  /// Invalid method parameter(s) error code.
+  static const invalidParams = -32602;
+  /// Generic extension error code.
+  static const extensionError = -32000;
+  /// Maximum extension provided error code.
+  static const extensionErrorMax = -32000;
+  /// Minimum extension provided error code.
+  static const extensionErrorMin = -32016;
+
 
   static String _errorCodeMessage(int errorCode) {
     _validateErrorCode(errorCode);
     if (errorCode == kInvalidParams) {
       return "Invalid params";
     }
     return "Server error";
   }
 
   static _validateErrorCode(int errorCode) {
@@ skipping 35 matching lines @@
 ///
 /// [method] - the method name of the service protocol request.
 /// [parameters] - A map holding the parameters to the service protocol request.
 ///
 /// *NOTE*: All parameter names and values are **encoded as strings**.
 typedef Future<ServiceExtensionResponse>
     ServiceExtensionHandler(String method, Map<String, String> parameters);
 
 /// Register a [ServiceExtensionHandler] that will be invoked in this isolate
 /// for [method]. *NOTE*: Service protocol extensions must be registered
-/// in each isolate and users of extensions must always specify a target
-/// isolate.
+/// in each isolate.
+///
+/// *NOTE*: [method] must begin with 'ext.' and you should use the following
+/// structure to avoid conflicts with other packages: 'ext.package.command'.
+/// That is, immediately following the 'ext.' prefix, should be the registering
+/// package name followed by another period ('.') and then the command name.
+/// For example: 'ext.dart.io.getOpenFiles'.
+///
+/// Because service extensions are isolate specific, clients using extensions
+/// must always include an 'isolateId' parameter with each RPC.
 void registerExtension(String method, ServiceExtensionHandler handler) {
   if (method is! String) {
     throw new ArgumentError.value(method,
                                   'method',
                                   'Must be a String');
   }
+  if (!method.startsWith('ext.')) {
+    throw new ArgumentError.value(method,
+                                  'method',
+                                  'Must begin with ext.');
+  }
   if (_lookupExtension(method) != null) {
     throw new ArgumentError('Extension already registered: $method');
   }
   if (handler is! ServiceExtensionHandler) {
     throw new ArgumentError.value(handler,
                                   'handler',
                                   'Must be a ServiceExtensionHandler');
   }
   _registerExtension(method, handler);
 }
@@ skipping 17 matching lines @@
 
 external _postEvent(String eventKind, String eventData);
 
 // Both of these functions are written inside C++ to avoid updating the data
 // structures in Dart, getting an OOB, and observing stale state. Do not move
 // these into Dart code unless you can ensure that the operations will can be
 // done atomically. Native code lives in vm/isolate.cc-
 // LookupServiceExtensionHandler and RegisterServiceExtensionHandler.
 external ServiceExtensionHandler _lookupExtension(String method);
 external _registerExtension(String method, ServiceExtensionHandler handler);