Node js response.write(average size html) takes forever for page to load

This is a simple web scraper.

The HTTP request is sent by NodeJS and response to the client with HTML. The console show body.toString() immediately, but on the browser it loads forever, when I stop the server, it display the page.

I did the similar things in express, it just works, but for some reason, I am not allowed to use express. So I have to write in pure NodeJS.

I have also tried to do it without HTTP request, only left the function response.write and response.end in the if statement, it is fine when I put a few strings in response.write, but when I put minify HTML inside response.write, same situation happen, loading takes forever and display the page when I stop the server.

The following is my code, any help is appreciated, thanks in advance.

    const url = require("url"),
      http = require('http');

    const port = 3000;  

    const requestHandler = (request, response) => {

      if (request.url === "/") {

        const options = {
          "method": "GET",
          "hostname": "something.com",
          "port": null,
          "path": "/",
          "headers": {
            "content-type": "multipart/form-data; boundary=----WebKitFormBoundary7MA4YWxkTrZu0gW",
          }
        };

        const req = http.request(options, function (res) {
          let chunks = [];

          res.on("data", function (chunk) {
            chunks.push(chunk);
          });

          res.on("end", function () {
            let body = Buffer.concat(chunks);
            console.log(body.toString());
            const html = body.toString();

            response.write(html);
            response.end();

          });
        });

        req.write("");
        req.end();

      }

    }

    const server = http.createServer(requestHandler)

    server.listen(port, (err) => {
      if (err) {
        return console.log('something bad happened', err)
      }

      console.log(`server is listening on ${port}`)
    })

via user3173952