Spark-Message-Router

An improved way to handle your Spark socket messages

Downloading

To use Spark-Message-Router, add it to your package manager with:

Gradle

compile "io.github.dszopa:message-router:1.2.0"

Maven

<dependency>
    <groupId>io.github.dszopa</groupId>
    <artifactId>message-router</artifactId>
    <version>1.2.0</version>
</dependency>

Usage

Routing

Inside of your websocket class, create a MessageRouter object. The objects parameter should be the package path where you plan on storing your routes

Then, in your @OnWebSocketMessage method, simply call messageRouter.handle with the Session & String parameters.

@Websocket
public class SocketHandler {
    
    private MessageRouter messageRouter = new MessageRouter("io.github.dszopa");
    
    ...
    
    @OnWebSocketMessage
    public void onMessage(Session user, String message) {
        messageRouter.handle(user, message);
    }
}

To configure routes, annotate a class with @MessageController and the method to be routed to with @Route

@MessageController
public class SimpleMessageRouter {
    
    @Route("/simpleMessage")
    public void simpleMessageHandler(Session user, String message) {
        System.out.println("Message received, Method routed!");
    }
}

In order to make sure that the method is properly routed to, websocket messages should be sent as JSON and include a route field

var webSocket = new Websocket('ws://localhost:4567/');

var message = JSON.stringify({
    route: "/simpleMessage"
});

webSocket.send(message);

With the code we have written, we will send a message with a route of /simpleRoute and have it mapped to the method simpleMessageHandler which will output its message.

Typed Messages

Using the annotation @MessageObject and specifying a typed object on the second parameter of a @Route method will automatically convert the incoming JSON message to an object of the specified type.

For example lets create a simple Person class

public class Person {
   
   private String name;
   
   public void getName() {
       return name;
   }
   
   public void setName(String name) {
       this.name = name;
   }
}

We can then have the incoming JSON's data field automatically converted into a Person object

@MessageController
public class SimpleMessageRouter {
   
   @Route("/customTypeMessage")
   public void customTypeMessageHandler(Session user, @MessageObject Person person) {
       System.out.println(person.getName());
   }
}

var webSocket = new Websocket('ws://localhost:4567/');

var message = JSON.stringify({
    route: "/simpleMessage",
    data: {
        name: "Simple Name:"
    }
});

webSocket.send(message);

Note: @MessageObject will only set the values of publicly available variables. Also variables with a setVariableName method will have their value set regardless of the variables scope since the setter is public.

Note: In Kotlin a warning message indicating an invalid call will be logged if a request tries to assign null values to non-nullable properties.

License

MIT License

Copyright (c) 2017 Daniel Szopa

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.