convert HTML ( having Javascript ) to PDF using JavaScript

We are also looking for some way to convert html files with complex javascript to pdf. The javasript in our files contains document.write and DOM manipulation.

We have tried using a combination of HtmlUnit to parse the files and Flying Saucer to render to pdf but the results are not satisfactory enough. It works, but in our case the pdf is not close enough to what the user wants.

If you want to try this out, here is a code snippet to convert a local html file to pdf.

URL url = new File("test.html").toURI().toURL();
WebClient webClient = new WebClient(); 
HtmlPage page = webClient.getPage(url);

OutputStream os = null;
try{
   os = new FileOutputStream("test.pdf");

   ITextRenderer renderer = new ITextRenderer();
   renderer.setDocument(page,url.toString());
   renderer.layout();
   renderer.createPDF(os);
} finally{
   if(os != null) os.close();
}

I'm surprised no one mentioned the possibility to use an API to do the work.

Granted, if you want to stay secure, converting HTML to PDF directly from within the browser using javascript is not a good idea.

But here's what you can do:

When your user hit the "Print" (for example) button, you:

  1. Send a request to your server at a specific endpoint with details about what to convert (URL of the page for instance).
  2. This endpoint will then send the data to convert to an API, and will receive the PDF in response
  3. which it will return to your user.

For a user point of view, they will receive a PDF by clicking on a button.

There are many available API that does the job, some better than others (that's not why I'm here) and a Google search will give you a lot of answers.

Depending on what is written your backend, you might be interested in PDFShift (Truth: I work there).

They offer ready to work packages for PHP, Python and Node.js. All you have to do is install the package, create an account, indicate your API key and you are all set!

The advantage of the API is that they work well in all languages. All you have to do is a request (generally POST) containing the data you want to be converted and get a PDF back. And depending on your usage, it's generally free, except if you are a heavy user.