@tsed/socketio

@tsed/socketio

Experimental feature. You can contribute to improve this feature !

A package of Ts.ED framework. See website: https://romakita.github.io/ts-express-decorators/

Socket.io enable real-time bidirectional event-based communication. It works on every platform, browser or device, focusing equally on reliability and speed.

Installation

Before using the Socket.io, we need to install the Socket.io module.

npm install --save socket.io @types/socket.io @tsed/socketio

Then add the following configuration in your ServerLoader:

import {ServerLoader, ServerSettings} from "@tsed/common";
import "@tsed/socketio"; // import socketio Ts.ED module
import Path = require("path");
const rootDir = Path.resolve(__dirname)

@ServerSettings({
    rootDir,
    socketIO: {
        // ... see configuration
    }
})
export class Server extends ServerLoader {

}

Socket Service

Socket.IO allows you to “namespace” your sockets, which essentially means assigning different endpoints or paths. This is a useful feature to minimize the number of resources (TCP connections) and at the same time separate concerns within your application by introducing separation between communication channels. See namespace documentation.

All Socket service work under a namespace and you can create one Socket service per namespace.

Example:

import * as SocketIO from "socket.io";
import {SocketService, IO, Nsp, Socket, SocketSession} from "@tsed/socketio";

@SocketService("/my-namespace")
export class MySocketService {

    @Nsp nsp: SocketIO.Namespace;

    constructor(@IO private io: SocketIO.Server) {}
    /**
     * Triggered the namespace is created
     */
    $onNamespaceInit(nsp: SocketIO.Namespace) {

    }
    /**
     * Triggered when a new client connects to the Namespace.
     */
    $onConnection(@Socket socket: SocketIO.Socket, @SocketSession session: SocketSession) {

    }
    /**
     * Triggered when a client disconnects from the Namespace.
     */
    $onDisconnect(@Socket socket: SocketIO.Socket) {

    }
}

@SocketService inherit from @Service decorator. That means, a SocketService can be injected to another Service, Controller or Middleware.

Declaring an Input Event

@Input decorator declare a method as a new handler for a specific event.

@SocketService("/my-namespace")
export class MySocketService {
    @Input("eventName")
    myMethod(@Args(0) userName: string, @Socket socket: SocketIO.Socket, @Nsp nsp: SocketIO.Namespace) {
        console.log(userName);
    }
}

• @Args <any|any[]>: List of the parameters sent by the input event.
• @Socket <SocketIO.Socket>: Socket instance.
• @Nsp <SocketIO.Namespace>: Namespace instance.

Send a response

You have a many choice to send a response to your client. Ts.ED offer some decorators to send a response:

Example:

@SocketService("/my-namespace")
export class MySocketService {
    @Input("eventName")
    @Emit("responseEventName") // or Broadcast or BroadcastOthers
    async myMethod(@Args(0) userName: string, @Socket socket: SocketIO.Socket) {
        return "Message " + userName;
    }
}

The method accept a promise as returned value.

!> Return value is only possible when the method is decorated by @Emit, @Broadcast and @BroadcastOthers.

Socket Session

Ts.ED create a new session for each socket.

@SocketService("/my-namespace")
export class MySocketService {
    @Input("eventName")
    @Emit("responseEventName") // or Broadcast or BroadcastOthers
    async myMethod(@Args(0) userName: string, @SocketSession session: SocketSession) {

        const user = session.get("user") || {}
        user.name = userName;

        session.set("user", user);

        return user;
    }
}

Documentation

See our documentation https://romakita.github.io/ts-express-decorators/#/api/index