NodeJS execute flow in background (server side) and grab the html

I am having a website which has many sections and multiple pages in each section.

There is a feature called "Generate PDF" which will traverse through all the sections and pages one by one and grab the HTML from the browser and then generate its PDF. This is working fine as of now.

But this is holding the user from doing anything until the PDF is generated.

I want to have some help on how I can do the same process in background (on server side) ? I have heard from someone that node-curl may help in this but I am not familiar with that.

Can anyone suggest me some ways to proceed further?

If anyone aware about node-curl and just can give hint that it may help me to resolve the issue then also it will be good. I will learn about it and invest my time to get it done.

Or else if someone came across the same kind of problem and have any idea then it will be good.

I am open to use any npm to get it done.

We are also using EmberJs so if any suggestions on that part then also welcomed.

Thank you.