io-bus

Add io-bus middleware to your express application to provide MsgBus interface between all Apps hosted in this server

To start the built-in server

Run this command in a terminal

io-server {port}

And include http://{host}:{port}/io-bus/web-client.js in your web app to utilize the MsgBus features: (publish,request,on,off,once,is_connected)

Server side code

var ioBus = require("io-bus");
var express = require("express");
var app = express();
var httpServer = app.listen(3000, function() {});

var sample_data = {
	users: 1000
};

ioBus(9666).connect("BackendServices", function(msgBus) {
	msgBus.addRequestHandler("GetData", function(params, from) {
		return sample_data;
	});
	msgBus.addRequestHandler("AddUser", function(params, from) {
		sample_data.users += params.users;
		msgBus.publish("DataUpdated", sample_data);
		return sample_data;
	});
});

app.use(
	ioBus.inject({
		snippet:
			'<script src="http://localhost:9666/io-bus/web-client.js"></script>'
	})
);

app.use("/", express.static("./static/", { index: "index.html" }));

client side usage

<button id="UpdateUsers">Update</button>
<script>
    window.addEventListener("DOMContentLoaded",function(){

        var ioBus = MsgBus("MyClientID",function(connected){//connection callback
            if(connected){
                ioBus.on('DataUpdated',function(msg){
                   console.log('Data has been updated');
                   console.log(msg.data);
                });

                ioBus.request('GetData').then(function(response){
                   //Refresh UI
                   console.log('GetData responded');
                   console.log(response.data);
                   ioBus.publish("UIUpdated",{users:response.data.users});
                })
            }
        });

        document.getElementById('UpdateUsers').addEventListener('click',function(){
            ioBus.request('AddUser',{users:1}).then(
                function(response){
                    console.log("AddUser Succeeded");
                    console.log(response.data);
                },
                function(err){// mostly from disconnected socket
                    console.error(err);
                }
            );
        });

    })

</script>