Merge pull request #57 from IOT-DSA/features/timeout_ws_connection

add timeout on ws connection

Author: rinick

lib/io.dart

@@ -92,11 +92,13 @@ class HttpHelper {
     }
 
     if (useStandardWebSocket == true && uri.scheme != "wss") {
-      return await WebSocket.connect(
+      return await awaitWithTimeout(WebSocket.connect(
         url,
         protocols: protocols,
         headers: headers
-      );
+      ), 60000, onSuccessAfterTimeout: (WebSocket socket){
+        socket.close();
+      });
     }
 
     if (uri.scheme != "ws" && uri.scheme != "wss") {
@@ -191,6 +193,9 @@ class HttpHelper {
           serverSide: false
         );
       });
+    }).timeout(new Duration(minutes: 1), onTimeout:(){
+      _client.close(force: true);
+      throw new WebSocketException('timeout');
     });
   }
 

lib/src/http/client_link.dart

@@ -141,6 +141,7 @@ class HttpClientLink extends ClientLink {
     // https://github.com/dart-lang/sdk/issues/31275
     // When it is fixed, we should go back to a regular try-catch
     runZoned(() async {
+    await ()async{
       HttpClientRequest request = await client.postUrl(connUri);
       Map requestJson = {
         'publicKey': privateKey.publicKey.qBase64,
@@ -198,7 +199,10 @@ class HttpClientLink extends ClientLink {
       if (serverConfig['format'] is String) {
         format = serverConfig['format'];
       }
-
+    }().timeout(new Duration(minutes: 1), onTimeout:(){
+        _client.close(force: true);
+        throw new Exception('timeout');
+    });
       await initWebsocket(false);
     }, onError: (e, s) {
       logger.warning("Client socket crashed: $e $s");
@@ -227,10 +231,8 @@ class HttpClientLink extends ClientLink {
         wsUrl = '$wsUrl$tokenHash';
       }
 
-      var socket = await HttpHelper.connectToWebSocket(
-        wsUrl,
-        useStandardWebSocket: useStandardWebSocket
-      );
+      var socket = await HttpHelper.connectToWebSocket(wsUrl,
+              useStandardWebSocket: useStandardWebSocket);
 
       _wsConnection = new WebSocketConnection(
           socket,

lib/src/utils/promise_timeout.dart

@@ -0,0 +1,38 @@
+part of dslink.utils;
+
+Future<T> awaitWithTimeout<T>(Future<T> future, int timeoutMs,
+    {Function onTimeout = null,
+    Function onSuccessAfterTimeout = null,
+    Function onErrorAfterTimeout = null}) {
+  Completer<T> completer = new Completer();
+
+  Timer timer = new Timer(new Duration(milliseconds: timeoutMs), () {
+    if (!completer.isCompleted) {
+      if (onTimeout != null) {
+        onTimeout();
+      }
+      completer.completeError(new Exception('Future timeout before complete'));
+    }
+  });
+  future.then((T t) {
+    if (completer.isCompleted) {
+      if (onSuccessAfterTimeout != null) {
+        onSuccessAfterTimeout(t);
+      }
+    } else {
+      timer.cancel();
+      completer.complete(t);
+    }
+  }).catchError((err) {
+    if (completer.isCompleted) {
+      if (onErrorAfterTimeout != null) {
+        onErrorAfterTimeout(err);
+      }
+    } else {
+      timer.cancel();
+      completer.completeError(err);
+    }
+  });
+
+  return completer.future;
+}

lib/utils.dart

@@ -17,6 +17,7 @@ part "src/utils/codec.dart";
 part "src/utils/dslink_json.dart";
 part "src/utils/list.dart";
 part "src/utils/uri_component.dart";
+part "src/utils/promise_timeout.dart";
 
 typedef ExecutableFunction();
 typedef T Producer<T>();