Fix HTTP sample implementation to actually wait for connections before attempting to write.

samples/tests/samples/src/chat/ChatServerTest.dart

 // Copyright (c) 2011, 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.
 //
 // VMOptions=
 // VMOptions=--short_socket_read
 // VMOptions=--short_socket_write
 // VMOptions=--short_socket_read --short_socket_write
 
 
@@ skipping 47 matching lines @@
         var responseData = JSON.parse(data);
         Expect.equals("leave", responseData["response"]);
 
         // Test done.
         statusPort.send("Test succeeded", null);
       }
 
       Map messageRequest = new Map();
       messageRequest["request"] = "leave";
       messageRequest["sessionId"] = sessionId;
-      request = httpClient.open("POST", "127.0.0.1", port, "/leave");
-      request.writeString(JSON.stringify(messageRequest));
-      request.responseReceived =
-          void _(HTTPClientResponse r) {
-            response = r;
-            response.dataEnd = leaveResponseHandler;
-          };
-      request.writeDone();
+      httpClient.openHandler = (HTTPClientRequest request) {
+        print('leave');
+        request.writeString(JSON.stringify(messageRequest));
+        request.writeDone();
+        request.responseReceived = (HTTPClientResponse r) {
+          print('leave response');
+          response = r;
+          response.dataEnd = leaveResponseHandler;
+        };
+      };
+      httpClient.open("POST", "127.0.0.1", port, "/leave");
     }
 
     void receive() {
       HTTPClientRequest request;
       HTTPClientResponse response;
 
       void receiveResponseHandler(String data) {
         Expect.equals(HTTPStatus.OK, response.statusCode);
         var responseData = JSON.parse(data);
         Expect.equals("receive", responseData["response"]);
@@ skipping 28 matching lines @@
           Expect.equals(messagesToReceive, messageCount);
           Expect.equals(totalClients, joinCount);
           leave();
         }
       }
 
       Map messageRequest = new Map();
       messageRequest["request"] = "receive";
       messageRequest["sessionId"] = sessionId;
       messageRequest["nextMessage"] = receiveMessageNumber;
-      request = httpClient.open("POST", "127.0.0.1", port, "/receive");
-      request.writeString(JSON.stringify(messageRequest));
-      request.responseReceived =
-          void _(HTTPClientResponse r) {
-            response = r;
-            response.dataEnd = receiveResponseHandler;
-          };
-      request.writeDone();
+      httpClient.openHandler = (HTTPClientRequest request) {
+        print('receive');
+        request.writeString(JSON.stringify(messageRequest));
+        request.writeDone();
+        request.responseReceived = (HTTPClientResponse r) {
+          print('receive response');
+          response = r;
+          response.dataEnd = receiveResponseHandler;
+        };
+      };
+      httpClient.open("POST", "127.0.0.1", port, "/receive");
     }
 
     void sendMessage() {
       HTTPClientRequest request;
       HTTPClientResponse response;
 
       void sendResponseHandler(String data) {
         Expect.equals(HTTPStatus.OK, response.statusCode);
         var responseData = JSON.parse(data);
         Expect.equals("message", responseData["response"]);
         sendMessageNumber++;
         if (sendMessageNumber < messagesToSend) {
           sendMessage();
         } else {
           receive();
         }
       }
 
       Map messageRequest = new Map();
       messageRequest["request"] = "message";
       messageRequest["sessionId"] = sessionId;
       messageRequest["message"] = "message " + sendMessageNumber;
-      request = httpClient.open("POST", "127.0.0.1", port, "/message");
-      request.writeString(JSON.stringify(messageRequest));
-      request.responseReceived =
-          void _(HTTPClientResponse r) {
-            response = r;
-            response.dataEnd = sendResponseHandler;
-          };
-      request.writeDone();
+      httpClient.openHandler = (HTTPClientRequest request) {
+        print('message');
+        request.writeString(JSON.stringify(messageRequest));
+        request.writeDone();
+        request.responseReceived = (HTTPClientResponse r) {
+          print('message response');
+          response = r;
+          response.dataEnd = sendResponseHandler;
+        };
+      };
+      httpClient.open("POST", "127.0.0.1", port, "/message");
     }
 
     void join() {
       HTTPClientRequest request;
       HTTPClientResponse response;
 
       void joinResponseHandler(String data) {
         Expect.equals(HTTPStatus.OK, response.statusCode);
         var responseData = JSON.parse(data);
         Expect.equals("join", responseData["response"]);
         sessionId = responseData["sessionId"];
         Expect.isTrue(sessionId != null);
 
         joinCount = 0;
         messageCount = 0;
         sendMessageNumber = 0;
         receiveMessageNumber = 0;
         sendMessage();
       }
 
       Map joinRequest = new Map();
       joinRequest["request"] = "join";
       joinRequest["handle"] = "test1";
-      request = httpClient.open("POST", "127.0.0.1", port, "/join");
-      request.writeString(JSON.stringify(joinRequest));
-      request.responseReceived =
-          void _(HTTPClientResponse r) {
-            response = r;
-            response.dataEnd = joinResponseHandler;
-          };
-      request.writeDone();
+      httpClient.openHandler = (HTTPClientRequest request) {
+        print("join");
+        request.writeString(JSON.stringify(joinRequest));
+        request.writeDone();
+        request.responseReceived = (HTTPClientResponse r) {
+          print("join response");
+          response = r;
+          response.dataEnd = joinResponseHandler;
+        };
+      };
+      print('opening for join');
+      httpClient.open("POST", "127.0.0.1", port, "/join");
     }
 
     this.port.receive(
         void _(var message, SendPort replyTo) {
           totalClients = message.totalClients;
           messagesToSend = message.messagesToSend;
           messagesToReceive = message.messagesToReceive;
           port = message.port;
           statusPort = replyTo;
 
@@ skipping 111 matching lines @@
   TestMain testMain = new TestMain.start(10, 2);
 }
 
 
 void main() {
   testOneClient();
   testTwoClients();
   testTwoClientsMoreMessages;
   testTenClients();
 }