nope/lib/communication/IoSocketServer.ts

import { Server } from "http";
import * as io from 'socket.io';
import { Logger } from "winston";
import { ICommunicationInterface } from "../dispatcher/nopeDispatcher";
import { getLogger } from "../logger/getLogger";

/**
 * Communication Layer using IO-Sockets.
 *
 * @export
 * @class IoSocketServer
 * @implements {ICommunicationInterface}
 */
export class IoSocketServer implements ICommunicationInterface {

    protected _socket: io.Server
    protected _sockets: Set<io.Socket>;
    protected _funcs: Map<string, (...args: any[]) => void>;
    protected _logger: Logger;

    /**
     * Creates an instance of IoSocketServer.
     * @param {number} port The Port, on which the Server should be hosted
     * @param {Server} [server] A Server shich should be used. (Otherwise a Server is created)
     * @memberof IoSocketServer
     */
    constructor(public port: number, server?: Server) {
        if (server) {
            this._socket = (io as any)(server);
        } else {
            this._socket = (io as any)();
        }

        this._logger = getLogger('info', 'IO-Socket');

        this._socket.listen(port);

        const _this = this;
        this._socket.on('connection', (client) => {

            _this._logger.debug('New Connection established: ' + client.id);

            // Add the Elements to the Client
            _this._sockets.add(client);

            // Subscribe to Loosing connection:
            client.on('disconnect', () => {
                _this._logger.debug('Connection of : ' + client.id + ' lost.');
                _this._sockets.delete(client);
            });

            for (const [id, _func] of _this._funcs) {
                // Subscribe to the Events:
                client.on(id, (...args) => {
                    _this._logger.debug('received content: ', ...args);

                    // Forward the Message.
                    _func(...args);
                });
            }
        });

        this._sockets = new Set();
        this._funcs = new Map<string, (...args: any[]) => void>();
    }
    off(event: string, cb: (...args: any[]) => void) {

        // Remove the Subscription from the Socket.
        for (const socket of this._sockets) {
            socket.off(event, cb);
        }

        // Remove the Function.
        this._funcs.delete(event);
    }

    on(event: string, cb: (...args: any[]) => void) {

        // Add the Subscription to the Sockets.
        for (const socket of this._sockets) {
            socket.on(event, cb);
        }

        // Store the Function
        this._funcs.set(event, cb);
    }

    send(event: string, data: any): void {
        this._logger.debug('sending data on: ' + event);
        this._socket.emit(event, data);
    }
}