Method respond

packages/engine.io/lib/transports/polling.ts:280–286

(data)

    };

    const respond = (data) => {
      headers["Content-Length"] =
        "string" === typeof data ? Buffer.byteLength(data) : data.length;
      this.res.writeHead(200, this.headers(this.req, headers));
      this.res.end(data);
      callback();
    };

    if (!this.httpCompression || !options.compress) {
      respond(data);