Convert and download html to pdf without saving file

Below is the module for convert html to pdf file "html-pdf", 

Install the html-pdf

$ npm install -g html-pdf

example for convert html to pdf 

var pdf = require('html-pdf');
var options = { format: 'Letter' };
 
pdf.create('<h1>Welcome</h1>', options).toFile('./sample.pdf', function(err, res) {
  if (err) return console.log(err);
  console.log(res);
});

Below is the api code for download file without saving,

router.get('/downloadfile', function(req, res, next) {
  pdf.create("<h1 style='text-align:center'>Hi Welcome</h1><br><img src='https://www.google.com/images/branding/googlelogo/1x/googlelogo_color_272x92dp.png'>").toStream(function (err, stream) {
    if (err) {
        console.log(err);
    }
    res.writeHead(200, {
        'Content-Type': 'application/force-download',
        'Content-disposition': 'attachment; filename=file.pdf'
    });
    stream.pipe(res);
  });
});

Basically, it will not work in ajax calls, it will work only when page load, from the client side we need to call the API,  like 

window.open('https://www.domain.com//downloadfile','download');