node_modules/engine.io/build/transports/websocket.js

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.WebSocket = void 0;
const transport_1 = require("../transport");
const debug_1 = require("debug");
const debug = (0, debug_1.default)("engine:ws");
class WebSocket extends transport_1.Transport {
    /**
     * WebSocket transport
     *
     * @param {http.IncomingMessage}
     * @api public
     */
    constructor(req) {
        super(req);
        this.socket = req.websocket;
        this.socket.on("message", (data, isBinary) => {
            const message = isBinary ? data : data.toString();
            debug('received "%s"', message);
            super.onData(message);
        });
        this.socket.once("close", this.onClose.bind(this));
        this.socket.on("error", this.onError.bind(this));
        this.writable = true;
        this.perMessageDeflate = null;
    }
    /**
     * Transport name
     *
     * @api public
     */
    get name() {
        return "websocket";
    }
    /**
     * Advertise upgrade support.
     *
     * @api public
     */
    get handlesUpgrades() {
        return true;
    }
    /**
     * Advertise framing support.
     *
     * @api public
     */
    get supportsFraming() {
        return true;
    }
    /**
     * Writes a packet payload.
     *
     * @param {Array} packets
     * @api private
     */
    send(packets) {
        const packet = packets.shift();
        if (typeof packet === "undefined") {
            this.writable = true;
            this.emit("drain");
            return;
        }
        // always creates a new object since ws modifies it
        const opts = {};
        if (packet.options) {
            opts.compress = packet.options.compress;
        }
        const send = data => {
            if (this.perMessageDeflate) {
                const len = "string" === typeof data ? Buffer.byteLength(data) : data.length;
                if (len < this.perMessageDeflate.threshold) {
                    opts.compress = false;
                }
            }
            debug('writing "%s"', data);
            this.writable = false;
            this.socket.send(data, opts, err => {
                if (err)
                    return this.onError("write error", err.stack);
                this.send(packets);
            });
        };
        if (packet.options && typeof packet.options.wsPreEncoded === "string") {
            send(packet.options.wsPreEncoded);
        }
        else {
            this.parser.encodePacket(packet, this.supportsBinary, send);
        }
    }
    /**
     * Closes the transport.
     *
     * @api private
     */
    doClose(fn) {
        debug("closing");
        this.socket.close();
        fn && fn();
    }
}
exports.WebSocket = WebSocket;