I'm trying to build a GWT (2.4.0) application that can communicate (full-duplex) with a server using a text-based protocol. To accomplish this I'm using Kaazing Websocket Gateway Version 3.3.2 to act as a proxy.
GWT App <-----[websocket]-----> Kaazing <-----[tcp]-----> Backend Server
This is my Kaazing configuration:
<service>
<accept>ws://127.0.0.1:9444/foobar</accept>
<connect>tcp://localhost:50189</connect>
<type>proxy</type>
<cross-site-constraint>
<allow-origin>http://127.0.0.1:8888</allow-origin>
</cross-site-constraint>
</service>
This setup works with the Java implementation of the Kaazing client. Now I want to use this service in a GWT application.
This is my Code for the GWT client implementation:
WebSocket ws;
try {
ws = new WebSocket("ws://127.0.0.1:9444/foobar");
ws.addCloseHandler(new CloseHandler() {
#Override
public void onClose(CloseEvent ev) {
}
});
ws.addMessageHandler(new MessageHandler() {
#Override
public void onMessage(MessageEvent ev) {
System.out.println(ev.getData());
}
});
ws.addOpenHandler(new OpenHandler() {
#Override
public void onOpen(OpenEvent ev) {
}
});
} catch (WebSocketException e) {
e.printStackTrace();
}
The GWT client can successfully send text to the backend server. It just can't process any response from the server. A JavaScript Exception is thrown as soon as ev.getData() is called.
Uncaught JavaScript exception [Uncaught java.lang.ClassCastException: com.google.gwt.core.client.JavaScriptObject$ cannot be cast to java.lang.String]
If I change the WebSocket address in the code above to ws://127.0.0.1:9444/echo to use the Kaazing echo service, any text I send is successfully received by the GWT application. If I change the service back to proxy (or broadcast) the above JavaScript exception is thrown every time a message from the server is received.
The same code in a Java program (using the Kaazing java client) works just fine.
As I am no GWT expert, is there any way I can further debug the problem or is there a simple solution I just fail to see?
I believe I've seen that issue before, do you mind sharing your gwtclient.gwt.xml file content? Or, maybe, try adding '' or '' depending on whether you are using ByteSocket or WebSocket in the 'gwtclient.gwt.xml' of the GWT client.
Hope this helps,
-Marcelo
Related
I deployed my ASP.NET application to a remote server with a hosting company, and when i try to send data from Postman, i get the internal server error with no definite error message. I have set custom error mode to off in the web config file. please can anyone help me? I have checked for several solutions but nothing.
PS: i am new to ASP.NET deployment with other companies apart from Azure
In this case, you should log error to file to see what issues in deployment mode.
This way i implemented global error log.
public class ExceptionHandlingAttribute : ExceptionFilterAttribute
{
public override void OnException(HttpActionExecutedContext context)
{
//Log Critical errors
// You can use log4net library and configure log folder
}
}
In WebApiConfig.cs file you register it.
public static void Register(HttpConfiguration config)
{
// .....
config.Filters.Add(new ExceptionHandlingAttribute());
}
When I am trying to connect solace VMR Server and deliver the messages from a Java client called Vertx AMQP Bridge.
I am able to connect the Solace VMR Server but after connecting, not able to send messages to solace VMR.
I am using below sender code from vertx client.
public class Sender extends AbstractVerticle {
private int count = 1;
// Convenience method so you can run it in your IDE
public static void main(String[] args) {
Runner.runExample(Sender.class);
}
#Override
public void start() throws Exception {
AmqpBridge bridge = AmqpBridge.create(vertx);
// Start the bridge, then use the event loop thread to process things thereafter.
bridge.start("13.229.207.85", 21196,"UserName" ,"Password", res -> {
if(!res.succeeded()) {
System.out.println("Bridge startup failed: " + res.cause());
return;
}
// Set up a producer using the bridge, send a message with it.
MessageProducer<JsonObject> producer =
bridge.createProducer("T/GettingStarted/pubsub");
// Schedule sending of a message every second
System.out.println("Producer created, scheduling sends.");
vertx.setPeriodic(1000, v -> {
JsonObject amqpMsgPayload = new JsonObject();
amqpMsgPayload.put(AmqpConstants.BODY, "myStringContent" + count);
producer.send(amqpMsgPayload);
System.out.println("Sent message: " + count++);
});
});
}
}
I am getting the error below:
Bridge startup failed: io.vertx.core.impl.NoStackTraceThrowable:
Error{condition=amqp:not-found, description='SMF AD bind response
error', info={solace.response_code=503, solace.response_text=Unknown
Queue}} Apr 27, 2018 3:07:29 PM io.vertx.proton.impl.ProtonSessionImpl
WARNING: Receiver closed with error
io.vertx.core.impl.NoStackTraceThrowable:
Error{condition=amqp:not-found, description='SMF AD bind response
error', info={solace.response_code=503, solace.response_text=Unknown
Queue}}
I have created queue and also topic correctly in solace VMR but not able to send/receive messages. Am I missing any configuration from solace VMR Server side? Is there any code-change required in the Vertx Sender Java code above? I am getting the error trace above when delivering message. Can someone help on the same?
Vertx AMQP Bridge Java client :https://vertx.io/docs/vertx-amqp-bridge/java/
There are a few different reason why you may be encountering this error.
It could be that the client is not authorized to publish guaranteed messages. To fix this, you need to enable "guaranteed endpoint create" in the client-profile on the Solace router side.
It may also be that the application is using Reply Handling. This is not currently supported with the Solace router. Support for this will be added in the 8.11 release of the Solace VMR. A workaround for this would be to set ReplyHandlingSupport to false.
AmqpBridgeOptions().setReplyHandlingSupport(false);
There is also a known issue in the Solace VMR which causes this error when unsubscribing from a durable topic endpoint. A fix for this issue will also be in the 8.11 release of the Solace VMR. A workaround for this is to disconnect the client without first unsubscribing.
I novice in camel.
What i have:
- rest app deployed on tomcat
- mongodb
What i want to do:
I want to send request from rest app to camel and camel send request to mongodb and then camel send response to the rest app. (request rest -> camel -> mongodb , response mongodb->camel->rest )
I can't find information about it.
how i can do this?
my Rest class
#Path("/leave")
public class Leave {
#GET
#Path("/all")
#Produces("application/json")
public String getLeaveRequestList(){
return "{\"status\":200}";
}}
my route
public class CamelRouteConfig extends RouteBuilder {
#Override
public void configure() throws Exception {
restConfiguration().host("localhost").port(8080);
rest("/leave")
.post("/all")
.consumes("application/json")
.to("stream:out");
}
}
it do nothing. why? - i have no idea
contex method
CamelRouteConfig routeConfig = new CamelRouteConfig();
CamelContext context = new DefaultCamelContext();
try {
context.addRoutes(routeConfig);
context.start();
}finally {
context.stop();
}
thx for your attention!
You are running Camel as standalone. When you call context.start(), the method does not block. It means that after starting, context.stop() is called immediately. Camel shuts down and REST service goes down with it.
See the following articles: Running Camel standalone and have it keep runninge and running Camel standalone.
Use class org.apache.camel.main.Main and use run() method:
From run javadoc:
Runs this process with the given arguments, and will wait until completed, or the JVM terminates.
Throws:
Exception
I'm trying to create a SOAP service in AEM 6.2 (the client cant make a REST call). Right now its up and works, the problem is when we redeploy or the AEM instance is reset... then the port of the service gets locked. Error on "create()".
final JaxWsServerFactoryBean jaxWsServerFactoryBean = new JaxWsServerFactoryBean();
jaxWsServerFactoryBean.setServiceClass(getWebServiceClass());
jaxWsServerFactoryBean.setAddress(this.webServiceAddress);
jaxWsServerFactoryBean.setServiceBean(this);
jaxWsServerFactoryBean.getInInterceptors().add(new LoggingInInterceptor());
jaxWsServerFactoryBean.getOutInterceptors().add(new LoggingOutInterceptor());
server = jaxWsServerFactoryBean.create();
*ERROR* [OsgiInstallerImpl] org.apache.cxf.transport.http_jetty.JettyHTTPServerEngine Could not start Jetty server on port 4,517: Address already in use: bind
The first time I deploy works fine but then I have to change port for each redeploy... I'm closing the server if exists before that create, and if I call "isStarted()" it says false.
server.getDestination().shutdown();
server.stop();
server.destroy();
Really stuck for days on this, thank you for your help.
You should create a OSGI bundle and create your soap service inside the bundle.
#Activate
public void activate(BundleContext bundleContext) throws Exception {
... start your soap service
}
#Deactivate
public void deactivate() throws Exception {
... stop your soap service
}
Now you can restart your soap service by restarting the bundle. here is reference how to create a OSGI bundle. http://www.aemcq5tutorials.com/tutorials/create-osgi-bundle-in-aem/
Heroku recently began supporting Java apps. Looking through the docs, it seems to resemble the Java Servlet Standard. Does anyone know of an instance where a GWT app has been successfully deployed on Heroku? If so, are there any limitations?
Yes, I've got a successful deployment using the getting started with Java instructions here:
http://devcenter.heroku.com/articles/java
I use the Maven project with appassembler plugin approach but added gwt-maven-plugin to compile a GWT app during the build.
When you push to heroku you see the GWT compile process running, on one thread only so quite slow but it works fine.
The embedded Jetty instance is configured to serve up static resources at /static from src/main/resources/static and I copy the compiled GWT app to this location during the build and then reference the .nocache.js as normal.
What else do you want to know?
You've got a choice, either build the Javascript representation of your GWT app locally into your Maven project, commit it and the read it from your app, or to generate it inside Heroku via the gwt-maven-plugin as I mentioned.
The code to serve up files from a static location inside your jar via embedded Jetty is something like this inside a Guice ServletModule:
(See my other answer below for a simpler and less Guice-driven way to do this.)
protected void configureServlets() {
bind(DefaultServlet.class).in(Singleton.class);
Map<String, String> initParams = new HashMap<String, String>();
initParams.put("pathInfoOnly", "true");
initParams.put("resourceBase", staticResourceBase());
serve("/static/*").with(DefaultServlet.class, initParams);
}
private String staticResourceBase() {
try {
return WebServletModule.class.getResource("/static").toURI().toString();
}
catch (URISyntaxException e) {
e.printStackTrace();
return "couldn't resolve real path to static/";
}
}
There's a few other tricks to getting embedded Jetty working with guice-servlet, let me know if this isn't enough.
My first answer to this turned out to have problems when GWT tried to read its serialization policy. In the end I went for a simpler approach that was less Guice-based. I had to step through the Jetty code to understand why setBaseResource() was the way to go - it's not immediately obvious from the Javadoc.
Here's my server class - the one with the main() method that you point Heroku at via your app-assembler plugin as per the Heroku docs.
public class MyServer {
public static void main(String[] args) throws Exception {
if (args.length > 0) {
new MyServer().start(Integer.valueOf(args[0]));
}
else {
new MyServer().start(Integer.valueOf(System.getenv("PORT")));
}
}
public void start(int port) throws Exception {
Server server = new Server(port);
ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
context.setBaseResource(createResourceForStatics());
context.setContextPath("/");
context.addEventListener(new AppConfig());
context.addFilter(GuiceFilter.class, "/*", null);
context.addServlet(DefaultServlet.class, "/");
server.setHandler(context);
server.start();
server.join();
}
private Resource createResourceForStatics() throws MalformedURLException, IOException {
String staticDir = getClass().getClassLoader().getResource("static/").toExternalForm();
Resource staticResource = Resource.newResource(staticDir);
return staticResource;
}
}
AppConfig.java is a GuiceServletContextListener.
You then put your static resources under src/main/resources/static/.
In theory, one should be able to run GWT using the embedded versions of Jetty or Tomcat, and bootstrap the server in main as described in the Heroku Java docs.