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Monkey X Pro – 30% Discount

Monkey X ProA couple of days ago I received an e-mail by Blitz Research Ltd offering me a nice discount on Monkey X Pro, which I took advantage of. To show some love towards BRL and Monkey X Pro I thought I would share the offer here.

Monkey X Pro is a programming language for creating games which can be deployed to several targets including, but not limited to, Android, iOS, HTML5, Desktop, XNA, Ouya and more.

When you buy Monkey X Pro simply enter the coupon code MONKEYX30 for a 30% discount.

Now go buy it and support BRL!

Note: this offer is only available for a limited time and is available until 2nd June.

Convert HTML to PDF with HTML2PDF Web Service

HTML2PDF Web ServiceRecently I launched my new product HTML2PDF Web Service — a web service for converting HTML to PDF.

In this post I’d like to talk about HTML2PDF Web Service. Why to choose it, how to use it and what technologies were used to create it.

Why Choose HTML2PDF Web Service?

Programmatically generating PDF documents is a painful and time consuming problem that neither makes your developers nor designers happy. With HTML2PDF Web Service you can design your invoices or reports in HTML, style them with CSS and convert the resulting page into a PDF document. Using HTML2PDF Web Service saves your developers and designers time which is better spent making your product better.

Say your web application or mobile app (or any application for that matter) needs to generate invoices or reports in PDF format. Unless you can install special HTML to PDF conversion software you’re probably stuck with some of the libraries available for your language that can programmatically generate PDF documents. To do this you would probably design your document in something like MS Word, LibreOffice Writer or perhaps HTML. After this design has been approved you can start programming your PDF module; setting up coordinates, font sizes etc. And then all of the sudden you notice your library has limited support for doing actual document layouts and presenting tabular data that can span multiple lines. Now you need to write your own routines for splitting text over multiple lines, keep track of coordinates and make sure nothing overlaps. If like me you’ve already been there, it’s quite the nightmare.

So being able to design in HTML, style with CSS (heck, even use a bit of JavaScript) and convert the resulting page to PDF would speed up this process a lot. Am I starting to tickle your interest?

How to use HTML2PDF Web Service

Simply create your soon to be PDF documents in HTML, style them with CSS and if wanted you can use JavaScript as well. The final document is best previewed in a WebKit based browser such as Google Chrome, since that’s the technology HTML2PDF Web Service uses in the background to render the HTML and convert it to PDF.

Here are some examples on how to call the web service. Converting HTML to PDF is easy with the HTML2PDF Web Service. You can pass an URL to the page you want to convert or either send the HTML code with the request.


$ curl -H "X-API-Key: F8802062-4D31-11E3-8F59-BFD4058B6BFF"
       -H "X-API-Username: MyUsername"
       -d '{"content":"<html><head><title>My page</title></head><body><h1>Hello World!</h1><p>I am an HTML page converted to PDF!</p></body></html>"}'
       https://html2pdfwebservice.com/api/convert > page.pdf


#!/usr/bin/env perl
use strict;
use warnings;
use Mojo::UserAgent;

my $ua = Mojo::UserAgent->new;
my $tx = $ua->post(
    'https://html2pdfwebservice.com/api/convert' => {
        'X-API-Username' => 'MyUsername',
        'X-API-Key'      => 'F8802062-4D31-11E3-8F59-BFD4058B6BFF'
    } => json => {url => 'http://domain.com/invoice.html'}
if (my $res = $tx->success) {
    my $pdf_data = $res->body;


require 'net/https'
require 'uri'

uri           = URI.parse('https://html2pdfwebservice.com/api/convert')
https         = Net::HTTP.new(uri.host, uri.port)
https.use_ssl = true
# In case the SSL certificate isn't accepted
https.verify_mode = OpenSSL::SSL::VERIFY_NONE

req = Net::HTTP::Post.new(uri.path)
req['X-API-Username'] = 'MyUsername'
req['X-API-Key']      = 'F8802062-4D31-11E3-8F59-BFD4058B6BFF'
req.body              = '{"url": "http://domain.com/invoice.html"}'

res = https.request(req)
if res.code == '200'
    pdf_data = res.body
    # - or write to file -
    # File.open('invoice.pdf', 'w') { |file| file.write(res.body) }


$settings = array(
    'url' => 'http://domain.com/invoice.html',

$curl = curl_init();
curl_setopt($curl, CURLOPT_POST, 1);
curl_setopt($curl, CURLOPT_POSTFIELDS, json_encode($settings));
curl_setopt($curl, CURLOPT_HTTPHEADER, array(
    'X-API-Username: MyUsername',
    'X-API-Key: F8802062-4D31-11E3-8F59-BFD4058B6BFF'

curl_setopt($curl, CURLOPT_URL, 'https://html2pdfwebservice.com/api/convert');
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
// Helps to debug in case of issues
// curl_setopt($curl, CURLOPT_VERBOSE, 1);

// In case the SSL certificate isn't accepted because of outdated certificates
// on your server
curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);

$res = curl_exec($curl);
// Save PDF to disk
file_put_contents('document.pdf', $res);

Technologies used to develop HTML2PDF Web Service

The most interesting part in developing HTML2PDF Web Service was choosing which technology to use for converting HTML to PDF. After doing research on the subject and testing several solutions I eventually went with a WebKit based solution. By using WebKit it’s easier for the end user to preview their document using a WebKit based browser.

The HTML to PDF conversion server was developed using Go. Go is a fun language to program with, does concurrency in a really nice way and can produce a native executable for Linux, OS X, Windows and some other platforms. Thanks to Go the conversion server is fast, snappy and low on memory and CPU usage. Being able to create a binary executable allows me to sell the conversion server as a standalone product as well.

To get access to the web service there’s also a web application which is written in Perl. My favorite web framework of choice has become Mojolicious for quite some time now and thus HTML2PDF Web Service has been written with it. DBIx::Class has been used for database interaction and Validation::Class is used to validate all user inputted data.

Used databases are PostgreSQL and Redis. The former is used to store user accounts, subscriptions and more. The latter is used to keep track of token usage per user.

Sign up now for a free trial

If after reading all this and you’re still reading, please do sign up for a free trial. The trial gives full access to all the features of the web service so if you like it, please consider buying a subscription.

In case of any questions, please do contact me either through the comments on this page or send an e-mail to support at support@html2pdfwebservice.com.

Ordered a Nexus 7 tablet

Nexus-7-2013I just ordered a Nexus 7 (2013) tablet for a really nice price. I plan on using it for Android development and website testing. Together with my iPad 3 and Android phone this should cover a wide range of test cases. Now to decide if I should go with Xamarin C# or stick with Java…

Since I’m note a big fan of Java I’m leaning towards Xamarin but the yearly subscription costs are a bit steep if you’re not actually generating money out of mobile stuff. Still, with Xamarin it’s easier and maybe cheaper in the sense of time to develop for both Android and iOS since you can write the core of your application in C# and use that on both target platforms.

Monkey re-branded to Monkey X and comes with Desktop target

Monkey by Blitz Research Ltd has been re-branded to Monkey X. Monkey X focuses on multi-platform and multi-device game development. Monkey code translates to the language used by the platform. Javascript for HTML5 games for example and C#/XNA when targeting Xbox 360. Supported platforms are Windows, Mac OSX, Linux, Flash, HTML5, iOS, Android, WP7/8, Xbox 360 and more. Ouya as well!

With the re-branding also comes a new free version. Before, the free version only supported the HTML5 target but now also includes the desktop target. Other targets can be acquired by purchasing a Monkey X Pro license.

Now that the desktop target is freely available as well I think I’ll go give Monkey a try soon. I haven’t used BlitzMax in ages (and I consider it a dead end as well) and since Monkey is very similar to BlitzMax I don’t expect too much trouble to get adapted to it.