Add Router.defaultStream

lib/server.dart

 // Copyright (c) 2013, 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.
 
 /**
  * This library provides a simple API for routing HttpRequests based on thier
  * URL.
  */
 library route.server;
 
@@ skipping 14 matching lines @@
  * [serve] creates a new [Stream] of requests whose paths match against the
  * given pattern. Matching requests are not sent to any other streams created by
  * a server() call.
  *
  * [filter] registers a [Filter] function to run against matching requests. On
  * each request the filters that match are run in order, waiting for each to
  * complete since filters return a Future. If any filter completes false, the
  * subsequent filters and request handlers are not run. This way a filter can
  * prevent further processing, like needed for authentication.
  *
+ * Requests not matched by a call to [serve] are sent to the [defaultStream].
+ * If there's no subscriber to the defaultStream then a 404 is sent to the
+ * response.
+ * 
  * Example:
  *     import 'package:route/server.dart';
  *     import 'package:route/pattern.dart';
  *
  *     HttpServer.bind().then((server) {
  *       var router = new Router(server);
  *       router.filter(matchesAny(['/foo', '/bar']), authFilter);
  *       router.serve('/foo').listen(fooHandler);
  *       router.serve('/bar').listen(barHandler);
+ *       router.defaultStream.listen(send404);
  *     });
  */
 class Router {
-  final Stream<HttpRequest> incoming;
-  final Map<Pattern, StreamController> _controllers = new LinkedHashMap();
-  final Map<Pattern, Filter> _filters = new LinkedHashMap();
-
-  Router(this.incoming) {
-    incoming.listen(_handleRequest);
+  final Stream<HttpRequest> _incoming;
+  
+  final Map<Pattern, StreamController> _controllers = 
+      new LinkedHashMap<Pattern, StreamController>();
+      
+  final Map<Pattern, Filter> _filters = new LinkedHashMap<Pattern, Filter>();
+  
+  final StreamController<HttpRequest> _defaultController = 
+      new StreamController<HttpRequest>();
+  
+  /**
+   * Create a new Router that listens to the [incoming] stream, usually an
+   * instance of [HttpServer].
+   */
+  Router(Stream<HttpRequest> incoming) : _incoming = incoming {
+    _incoming.listen(_handleRequest);
   }
 
   /**
-   * Request whose URI matches [url] are sent the the stream created by this\
+   * Request whose URI matches [url] are sent the the stream created by this

[butlermatt, 2013/03/07 13:21:52]

double 'the'

    * method, and not sent to any other serve streams.
    */
   Stream<HttpRequest> serve(Pattern url) {
     var controller = new StreamController<HttpRequest>();
     _controllers[url] = controller;
     return controller.stream;
   }
 
   /**
    * A [Filter] returns a [Future<bool>] that tells the router whether to apply
    * the remaining filters and send requests to the streams created by [serve].
    *
    * If the filter returns true, the request is passed to the next filter, and
    * then to the first matching server stream. If the filter returns false, it's
    * assumed that the filter is handling the request and it's not forwarded.
    */
   void filter(Pattern url, Filter filter) {
     _filters[url] = filter;
   }
 
+  Stream<HttpRequest> get defaultStream => _defaultController.stream;
+  
   void _handleRequest(HttpRequest req) {
     bool cont = true;
     doWhile(_filters.keys, (Pattern pattern) {
       if (matchesFull(pattern, req.uri.path)) {
         return _filters[pattern](req).then((c) {
           cont = c;
           return c;
         });
       }
       return new Future.immediate(true);
     }).then((_) {
       if (cont) {
         bool handled = false;
         for (Pattern pattern in _controllers.keys) {
           if (matchesFull(pattern, req.uri.path)) {
             _controllers[pattern].add(req);
             handled = true;
             break;
           }
         }
         if (!handled) {
-          send404(req);
+          if (_defaultController.hasSubscribers) {
+            _defaultController.add(req);
+          } else {
+            send404(req);
+          }
         }
       }
     });
   }
 }
 
 void send404(HttpRequest req) {
   req.response.statusCode = HttpStatus.NOT_FOUND;
   req.response.addString("Not Found");
   req.response.close();
 }