Method onDataRequest

packages/engine.io/lib/transports-uws/polling.ts:113–204

* The client sends a request with data. * * @private

(req, res)

   * @private
   */
  onDataRequest(req, res) {
    if (this.dataReq) {
      // assert: this.dataRes, '.dataReq and .dataRes should be (un)set together'
      this.onError("data request overlap from client");
      res.writeStatus("500 Internal Server Error");
      res.end();
      return;
    }

    const expectedContentLength = Number(req.headers["content-length"]);

    if (!expectedContentLength) {
      this.onError("content-length header required");
      res.writeStatus("411 Length Required").end();
      return;
    }

    if (expectedContentLength > this.maxHttpBufferSize) {
      this.onError("payload too large");
      res.writeStatus("413 Payload Too Large").end();
      return;
    }

    const isBinary = "application/octet-stream" === req.headers["content-type"];

    if (isBinary && this.protocol === 4) {
      this.onError("invalid content");
      return res.writeStatus("400 Bad Request").end();
    }

    this.dataReq = req;
    this.dataRes = res;

    let buffer;
    let offset = 0;

    const headers = {
      // text/html is required instead of text/plain to avoid an
      // unwanted download dialog on certain user-agents (GH-43)
      "Content-Type": "text/html",
    };

    this.headers(req, headers);
    for (let key in headers) {
      res.writeHeader(key, String(headers[key]));
    }

    const onEnd = (buffer) => {
      this.onData(buffer.toString());
      this.onDataRequestCleanup();
      res.cork(() => {
        res.end("ok");
      });
    };

    res.onAborted(() => {
      this.onDataRequestCleanup();
      this.onError("data request connection closed prematurely");