socket-application

Socket Application Patterns

Class Hierarchy

Application (base)
  └── SocketApplication (TCP socket, extends Application)
        └── WebSocketApplication (WebSocket, extends SocketApplication)

WebSocketApplication extends SocketApplication, not Application directly. Connection management methods (sendByConnectionId, closeByConnectionId, getConnection, ping) are defined once in SocketApplication and inherited by WebSocketApplication.

SocketApplication Setup

TCP socket server using net.createServer:

const { SocketApplication, Router } = require("@axiosleo/koapp");

const router = new Router("/", { /* ... */ });

const app = new SocketApplication({
  routers: [router],
  port: 8081,
  ping: {
    open: true,
    interval: 1000 * 10,
    data: "this is a ping message",
  },
});

app.start();

Message protocol: JSON payload terminated by @@@@@@ delimiter.

{"path":"/test","method":"GET","query":{"test":123}}@@@@@@

WebSocketApplication Setup

WebSocket server using the ws library:

const { WebSocketApplication, Router } = require("@axiosleo/koapp");

const router = new Router("/", { /* ... */ });

const app = new WebSocketApplication({
  routers: [router],
  port: 8081,
  ping: {
    open: false,
    interval: 1000 * 3,
    data: "this is a ping message",
  },
});

app.start();

Message protocol: plain JSON string (no delimiter).

{"path":"/test","method":"GET","query":{"test":123}}

Ping Configuration

Both applications support automatic heartbeat via pingConfig:

Field	Type	Default	Description
open	boolean	false	Enable periodic ping
interval	number	300000 (5min)	Milliseconds between pings
data	any	"this is a ping message"	Payload sent with each ping