KMF Storage Plugin: Websocket Client & Server

This project contains two KMF Plugins:

• WebSocketGateway: acts as a server to another KMF Storage plugin such as LevelDB or RocksDB. In a nutshell, this plugin allows to open a remote access on any storage through a bi-bidirectional WebSocket persistent connection.
• WebSocketClientPlugin: allows to configure a model to load its elements through a WebSocket connection, and therefore through a gateway (client/server architecture). The assembly of both plugins allows to seamlessly work on a remote storage as a local one. Additionally the WebSocket Client plugin is delivered for Java and JavaScript platform, both embedded in the same Jar dependency.

Last versions:

• 4.27.2 compatible with KMF framework 4.27.x

Changelog

• 4.27.0 use Undertow in version 1.3.6
• 4.27.1 minor bug fix for events propagation
• 4.27.2 roomID are now optional (empty roomID will now be replaced by default)

Dependency

Simply add the following dependency to your maven project:

<dependency>
    <groupId>org.kevoree.modeling.plugin</groupId>
    <artifactId>websocket</artifactId>
    <version>REPLACE_BY_LAST_VERSION</version>
</dependency>

Gateway usage (Java only)

First, man has to instantiate another storage using a plugin such as levelDB. Considering the name of this storage localStorage*, the following code snippet expose this storage on a WebSocket port 8080. Please change the port according to your need.

import org.kevoree.modeling.plugin.WebSocketGateway;

WebSocketGateway.expose(localStorage, 8080).start();

WebSocketClientPlugin usage (Java)

The WebSocketClientPlugin should be instantiate on client side and configure as the CDN driver for a KMF model such as:

import org.kevoree.modeling.plugin.WebSocketClientPlugin;

WebSocketClientPlugin wsclient = new WebSocketClientPlugin("ws://localhost:" + PORT + "/yourRoom")

KModel model = dynamicMM.createModel(
        DataManagerBuilder
        .create()
        .withContentDeliveryDriver(wsclient)
        .build()
    );

This code use the generic reflexive model of KMF, please refer to the documentation to instantiate using your generate MetaModel. In addition, please not that you should replace localhost by the IP of the corresponding gateway, as well as the PORT. Finally the yourRoom correspond to your sharing zone. RoomID is optional and will be replaced by default in case of empty. In other words, clients was be isolated each others by using different roomID, in case of a shared model conversely the same room should be used.

WebSocketClientPlugin usage (JS)

The JavaScript version of WebSocketClientPlugin is feature similar to the Java version. First the plugin js file should be included in your browser script, such as:

<script src="plugin.websocket.js"></script>

Then in your JS code, just instantiate the client:

var wsClient = new org.kevoree.modeling.plugin.WebSocketClientPlugin("ws://localhost:6000/yourRoom");

and use it to instanciate the model similarly to the Java version.

var model = dynamicMM.createModel(org.kevoree.modeling.memory.manager.DataManagerBuilder.create().withContentDeliveryDriver(wsClient).build());

More info

To have more information about KMF distributed model usage, please visit the following tutorial step:

https://github.com/kevoree-modeling/tutorial/tree/master/step6_distribution

if you want to have more information about the JS/Java usage of KMF please visit the following tutorial step:

https://github.com/kevoree-modeling/tutorial/tree/master/step7_isomorphism