ms/packages/websocket/src/socket-io/socket.ts

import { EventEmitter } from 'events'

import { SocketIO } from "./interfaces";
import { Packet } from './packet';
import { PacketTypes, SubPacketTypes } from './types';
import { Client } from './client';
import { Namespace } from './namespace';

export class Socket extends EventEmitter implements SocketIO.Socket {
    nsp: Namespace;
    server: SocketIO.Server;
    adapter: SocketIO.Adapter;
    id: string;
    request: any;
    client: Client;
    conn: SocketIO.EngineSocket;
    rooms: { [id: string]: string; };
    acks: { [id: string]: Function; };
    connected: boolean;
    disconnected: boolean;
    handshake: SocketIO.Handshake;
    fns: any[];
    flags: { [key: string]: boolean };
    _rooms: string[];

    private events = [
        'error',
        'connect',
        'disconnect',
        'disconnecting',
        'newListener',
        'removeListener'
    ]

    constructor(nsp: Namespace, client: Client, query = {}) {
        super();
        this.nsp = nsp;
        this.server = nsp.server;
        this.adapter = this.nsp.adapter;
        this.id = nsp.name !== '/' ? nsp.name + '#' + client.id : client.id;
        this.client = client;
        this.request = client.request;
        this.conn = client.conn;
        this.rooms = {};
        this.acks = {};
        this.connected = true;
        this.disconnected = false;
        // this.handshake = this.buildHandshake(query);
        this.fns = [];
        this.flags = {};
        this._rooms = [];
    }

    get json() {
        this.flags.json = true;
        return this
    }

    get volatile() {
        this.flags.volatile = true;
        return this
    }
    get broadcast() {
        this.flags.broadcast = true;
        return this
    }
    get local() {
        this.flags.local = true;
        return this
    }

    to(room: string): SocketIO.Socket {
        if (!~this._rooms.indexOf(room)) this._rooms.push(room);
        return this;
    }
    in(room: string): SocketIO.Socket {
        return this.to(room);
    }
    use(fn: (packet: SocketIO.Packet, next: (err?: any) => void) => void): SocketIO.Socket {
        throw new Error("Method not implemented.");
    }
    send(...args: any[]): SocketIO.Socket {
        this.emit("message", ...args)
        return this;
    }
    write(...args: any[]): SocketIO.Socket {
        return this.send(...args);
    }
    join(rooms: string | string[], fn?: (err?: any) => void): SocketIO.Socket {
        if (!Array.isArray(rooms)) {
            rooms = [rooms];
        }
        rooms = rooms.filter((room) => {
            return !this.rooms.hasOwnProperty(room);
        });
        if (!rooms.length) {
            fn && fn(null);
            return this;
        }
        return this;
    }
    leave(name: string, fn?: Function): SocketIO.Socket {
        delete this.rooms[name];
        fn && fn(null)
        return this;
    }
    leaveAll(): void {
        this.adapter.delAll(this.id);
        this.rooms = {};
    }
    disconnect(close?: boolean): SocketIO.Socket {
        if (!this.connected) return this;
        if (close) {
            this.client.disconnect();
        } else {
            this.packet({ type: PacketTypes.MESSAGE, sub_type: SubPacketTypes.DISCONNECT });
            this.onclose('server namespace disconnect');
        }
        return this;
    }
    compress(compress: boolean): SocketIO.Socket {
        throw new Error("Method not implemented.");
    }
    error(err: any): void {
        this.packet({ type: PacketTypes.MESSAGE, sub_type: SubPacketTypes.ERROR, data: err });
    }

    // ==========================================
    buildHandshake(query): SocketIO.Handshake {
        let requestQuery = this.request.uri();
        return {
            headers: this.request.headers(),
            time: (new Date) + '',
            address: this.conn.remoteAddress,
            xdomain: !!this.request.headers.origin,
            secure: !!this.request.connection.encrypted,
            issued: +(new Date),
            url: this.request.url,
            query: Object.assign(query, requestQuery)
        }
    }
    emit(event: string, ...args: any[]): boolean {
        if (~this.events.indexOf(event)) {
            super.emit(event, ...args);
            // @ts-ignore
            return this;
        }

        let packet: Packet = {
            type: PacketTypes.MESSAGE,
            sub_type: (this.flags.binary !== undefined ? this.flags.binary : this.hasBin(args)) ? SubPacketTypes.BINARY_EVENT : SubPacketTypes.EVENT,
            name: event,
            data: args
        }

        // access last argument to see if it's an ACK callback
        if (typeof args[args.length - 1] === 'function') {
            if (this._rooms.length || this.flags.broadcast) {
                throw new Error('Callbacks are not supported when broadcasting');
            }
            // debug('emitting packet with ack id %d', this.nsp.ids);
            this.acks[this.nsp.ids] = args.pop();
            packet.id = this.nsp.ids++;
        }

        let rooms = this._rooms.slice(0);
        let flags = Object.assign({}, this.flags);

        // reset flags
        this._rooms = [];
        this.flags = {};

        if (rooms.length || flags.broadcast) {
            this.adapter.broadcast(packet, {
                except: [this.id],
                rooms: rooms,
                flags: flags
            });
        } else {
            // dispatch packet
            this.packet(packet, flags);
        }
        // @ts-ignore
        return this;
    }
    packet(packet: Packet, opts?: any) {
        packet.nsp = this.nsp.name;
        opts = opts || {};
        opts.compress = false !== opts.compress;
        this.client.packet(packet, opts);
    }
    onconnect() {
        this.nsp.connected[this.id] = this;
        this.client.sockets[this.id] = this;
        this.join(this.id);
        // let skip = this.nsp.name === '/' && this.nsp.fns.length === 0;
        // if (skip) {
        // debug('packet already sent in initial handshake');
        // } else {
        this.packet({
            type: PacketTypes.MESSAGE,
            sub_type: SubPacketTypes.CONNECT
        });
        // }
    }
    onclose(reason?: string) {
        if (!this.connected) return this;
        // debug('closing socket - reason %s', reason);
        this.emit('disconnecting', reason);
        this.leaveAll();
        this.nsp.remove(this);
        this.client.remove(this);
        this.connected = false;
        this.disconnected = true;
        delete this.nsp.connected[this.id];
        this.emit('disconnect', reason);
    }
    onpacket(packet: Packet) {
        switch (packet.sub_type) {
            // 2
            case SubPacketTypes.EVENT:
                this.onevent(packet);
                break;
            // 5
            case SubPacketTypes.BINARY_EVENT:
                this.onevent(packet);
                break;
            // 3
            case SubPacketTypes.ACK:
                this.onack(packet);
                break;
            // 6
            case SubPacketTypes.BINARY_ACK:
                this.onack(packet);
                break;
            // 1
            case SubPacketTypes.DISCONNECT:
                this.ondisconnect();
                break;
            // 4
            case SubPacketTypes.ERROR:
                this.onerror(new Error(packet.data));
        }
    }
    onerror(err: Error) {
        if (this.listeners('error').length) {
            this.emit('error', err);
        } else {
            console.error('Missing error handler on `socket`.');
            console.error(err.stack);
        }
    }
    ondisconnect() {
        this.onclose('client namespace disconnect')
    }
    onevent(packet: Packet) {
        if (null != packet.id) {
            // debug('attaching ack callback to event');
            this.dispatch(packet, this.ack(packet.id));
        } else {
            this.dispatch(packet);
        }
    }
    ack(id: number) {
        let sent = false;
        return (...args: any[]) => {
            if (sent) return;
            this.packet({
                id: id,
                type: PacketTypes.MESSAGE,
                sub_type: this.hasBin(args) ? SubPacketTypes.BINARY_ACK : SubPacketTypes.ACK,
                data: args
            });
            sent = true;
        }
    }
    onack(packet: Packet) {
        let ack = this.acks[packet.id];
        if ('function' == typeof ack) {
            // debug('calling ack %s with %j', packet.id, packet.data);
            ack.apply(this, packet.data);
            delete this.acks[packet.id];
        } else {
            // debug('bad ack %s', packet.id);
        }
    }
    dispatch(packet: Packet, ack?: Function) {
        if (ack) { this.acks[packet.id] = ack; }
        super.emit(packet.name, ...packet.data, ack)
    }
    private hasBin(obj: any) {
        return false;
    }
}