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Comment by beatpanda | Hacker News Reader

Right now I'm using PhantomJS to render an HTML page. It supports styling via CSS, multiple pages, etc etc. What advantages does this have?

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PhantomJS is a full web browser that just happens to output PDF's. This is a library to create PDF's with it's own layout model that shares nothing with HTML. Much simpler and low level.

Is it really simpler? I have to learn a DSL to create PDFs with this, whereas I can just use HTML in the other case.

You are using a school bus to transport one person.

But the bus is free and it works fine.

but it comes with schoolbus-type problems and you look ridiculous.

Our customers don't see it so it doesn't matter how we "look". We can re-use existing design assets and UI elements. I can embed SVG charts drawn by D3, or anything else I can otherwise do with "an entire school bus".

It's not like there is a direct translation from HTML to PDF. They don't really map 1:1. The PDF exported by a browser from an HTML page is an interpretation of that content. Converting from HTML is not a straightforward, reliable way to produce PDFs. Sometimes the process turns out beautiful, sometimes it turns out kind of shitty. Not to mention there are PDF features which are not supported by an HTML export (for example, forms).

A DSL designed for PDF creation is a much better way to approach this. It gives you way more control over what you're doing. Concerning pdfkit specifically, I think a JSON file is a gruesome way to design a PDF, but IMO it's still better than converting from HTML unless you're doing something very simple.

I sort of disagree, HTML as implemented in PhantomJs, wkhtmltopdf and all interactive browsers is incomplete for paged/print output. However HTML with CCS page media is pretty close to being a complete solution, unfortunately the only implementation currently is the commercial PrinceXML.

If someone (Apple or Google) would get wise and implement the full paged media spec then PhantomJS/wkhtmltopdf/your browser might be a viable option for full fidelity print output.

See: http://www.webkit.org/projects/printing/

http://www.princexml.com/

Until then our apps will have to suffer with one layout language for viewing (HTML) and have another for print like this lib.

Simpler as in the complexity of the library, a web browser is orders of magnitude more complex than this lib.

Simpler as in ease of use? Well that's subjective, some might find HTML easier than learning a new layout model, other might like something more focused on just PDF layout like this.

Side note: Under the hood, PhantomJS uses wkhtmltopdf. You can probably save yourself some overhead using the wkhtmltopdf binary directly.

No I believe both use QTWebkit directly.

It, it used QTWebkit directly. Wkhtmltopdf uses a forked version of Webkit with several PDF-specific enhancements (better support for paging, fixes a couple bugs, etc).

Thanks for clarifying!

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