Watermarks and User restrictions

Obviously I realise Pressbooks use a form of ex libris, passive watermark, for free output. What is the best way to implement such a watermark on a stand alone instance of PB? I want to be able to have a free and open platform and only charge users for later removing this watermark by manually removing it and doing further architecting and refining of the ebook by using our in-house desktop tools, should the user wish i.e. I don’t strictly need it to work in the way I imagine it does so at PB - presumably you are able to switch-off the watermark feature via a network plug-in? (possibly Pressbooks VIP, would that be, looking at diagnostics?) - though this option would be great.

Another alternative would be for the ability to restrict a user to create only one book per account. Can I do this through ‘User Accounts May be Registered’ (presumably that prevents a registered user from creating any book?)

For the second part of my question I have found an old (hasn’t been updated in a long while plugin Limit Blogs Per User. Seems to work so far, I will test further and report back

take a look. Those are the best options.


Un saludo Colomet - he vivido en España para 15 años y mis hijas son Españolas jaja.

Thanks for that, I had a look at those plugins, of which Restrict Content seems the most promising, the plugin I linked to also works in a no frills way but is old. But I don’t really want to charge people to use the platform, just us for creating eBooks and print ready pdfs, with proofing etc. away from the platform as a normal part of what we do.

So therefore with that approach I have two problems opening the site to full user registration as PB works at the moment. 1) A user once registered can make as many books as they like and 2) they can output as many Kindle, ePub books as they like, with no watermarks. Prince XMLPdf of course would have to be licensed, and is way beyond our means at the moment. DocRaptor seems a more workable commercial solution but I haven’t played with it and I’m not sure if the output quality can be full digital press ready as I know Prince can. Again how can the super administrator control output of this?

So do you use Restrict Content and can it work in the way described?


A quick note about DocRaptor — it is an API for Prince (Prince as a service). We use it on Pressbooks.com and other networks we host.

Hi Ned, thanks for that. Does that mean one needs to pay the same licence fee to Prince XML? (even with PB discount this is massive, to small independents and is only for non-commercial use at that). I ask because DocRaptors own terms allow a per book fee or a modest monthly cost.

No, you just pay DocRaptor.

That’s good to know, so does DocRaptor allow the same export flexibility as the server installed Prince XMl, because it seems a little stripped down on PB?

The question remains too, what approach would you recommend for injecting a ex libris watermark. I can do it by playing with the export module but I want to be able to switch it on off per book site?

:world_map::ceuta_and_melilla: :slight_smile:

  1. with RCP, they will have as many books as they wish, but they will pay for each one (is possible to create a limitation, should not be so complicate for a developer and fast if i´m not wrong)

  2. you can have different levels of restriction. Basic level, no print, just web books. Premium level, you can allow to export books. I did not use RCP (but I think both works in the same way), but with pro-sites you can choose for each membership type the plugins are available to the users, so mPDF can be just for premium users maybe (also you could create a limitation too, like if a user is basic, just 2 prints, if the user is premium, unlimited …)

By the way, maybe I´m lost with something, but I do not really see the difference with mPDF and Prince. Maybe because the type of books I work with, but mPDF works pretty good for us.

Is that the Valenciana bandera there Colomet? I lived there for 6 months, fond memories!

mPDF is not good enough in my tests for Digital Pre-press, non of the open-source XHTML to pdf solutions are. Prince XML is fabulous quality and really as far as I can see, the only game in town for cloud solutions. For desktop, I have no need since we use InDesign and Acrobat Pro, but again their desktop licence allows you to take pure xthml and css to pdf, which is the whole architectural model of PB and a production process of great interest since we use many tools, including Sigil.

BTW both Sigil (now Kindle export too) and Calibre have plugins to the Desktop version of Prince XML, which means you can produce print Digital PrePress directly from Sigil, using your base ePub as the starting point. The licence fee here (desktop) makes much more sense for publishing our own writer’s and self-publishing client’s books, which we don’t wish to be automated.

Maybe mPDF is not the best solution, but as it works as a plugin, is easy to configure and to make the people to pay if they wish to use it (maybe is a good solution for the beta phase). Other option requires the payment of a developer and the configuration.

But should not be complicate, as with RCP you can have memberships, you can create a way that allow just to export with a specifical membership level to use the exports. Or to hide all the exports and to create a plugin that activates again, so, just users that pay for the plugin would have the exports.

mPDF is not of production quality for Digital Pre Press, i.e. in our case Lightning Source or local offset. It won’t even parse fonts, or at least the last time I played with it it couldn’t. It’s only really useful therefore for pdf output from PB, nothing more. I don’t think in our case it would ever be fair to charge for that.

DocRaptor payment model is very workable if as Ned suggests it uses the full Prince api.

I might add we have a development team working with us now - I’m not a developer and my job is taken up as a small independent publisher. There are specific things I need them to do, including an interactive link to our new app in development, musical notation engraving, DRM for our shop (not via PB), transitioning to proper PB Github development, and direct submission to KDP/CreateSpace, we will happily share all of this, as open-source, back to this community.

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DocRaptor is exactly the same as Prince (it is Prince, just running on a remote server). It’s not stripped down in any way. In fact, it’s a bit easier, because it includes a few extra fonts by default (so some special characters that we would have had to explicitly add support for by adding fonts with Prince are supported with no extra effort when using DocRaptor).

@colomet Not sure what you mean about other options requiring payment of a developer. To use DocRaptor:

  1. Download https://github.com/pressbooks/pressbooks-docraptor/
  2. Add your DocRaptor API key to wp-config.php.

No step three.

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Thanks, Steve! We love to hear this :slight_smile:

You’re welcome Ned, it has always been my intention but even though I’ve been working with PB since 2013 (I think) I’ve stumbled around it in a pretty amateur way, up till now, not being a developer per se. The new guys have been asked to properly fork from Github so we share any developments. Now too that windows local development can be done using Trellis and therefore use output modules properly, it makes it a hugely simpler, Xampp has been frustrating.

Great about Docraptor because this makes Prince so much more viable and frankly affordable. I wasn’t clear in what I was saying about ‘stripped’ down - I meant the DocRaptor options page seemed more basic than the Prince/server one but I see why as the api allows more control, which is even better.

Just to add also for Colomet and further to what Ned said, you’ve never needed to pay a developer to install the Prince linux binary just a server or even shared server that allows development access - I quickly moved to Webfaction early on. The PB documentation is quite straight forward and helpful too.

To be able to allow or not to allow to export the book as pdf after the payment. With mPDF is pretty easy as it works as a wordrpess plugin. So with a system of User restrictions, will work without problems.

But as Docraptor it wors also as plugin (I did not know about https://github.com/pressbooks/pressbooks-docraptor/) it will work in the same way as mPDF