Guest Speaker Peter Rabbitson at Perl::Dancer Conference

We managed to get Peter Rabbitson also known as ribasushi as guest speaker for our conference in October.

Peter is very famous for being the master mind and release manager for DBIx::Class, the most popular ORM in the Perl world. He also plays an important role in the Perl community and goes long ways to help people.

Getting experts to the conference isn't possible without sponsors, please check if you can support us. Every contribution will be helpful, please checkout our sponsoring page and/or contact me by email.

Please note that amount of tickets for the conference are limited, better register now and save money with early bird prices!

If you want to hear about a specific subject from Peter, please let us know and we will pass your suggestion on to him.

Enjoy
Racke

Asynchronous Task Distribution with AnyEvent and ZeroMQ

Some months ago i wrote how to (ab)use your database as a messagequeue in order to distribute tasks among worker-processes.

"From your code, it also looks like having more than one demon will put you at risk of processing the same jobs more than once." (Jerome Eteve)

"Abuse" is the right word. The moment you hit more than three concurrent jobs, you will see a nasty slowdown ..." (rob.kinyon)

The comments made pretty clear that this was not a good idea and I promised to clean up. (Note: it worked pretty well but only as long as you didnt upscale the system)

Here we go!

I decided to go with ZeroMQ as a messagequeue and ZMQx::Class + AnyEvent.

Processing tasks takes some time in my project (5 seconds up to 20 minutes) and are of varying priority. So I cannot have some low priority task delay incoming high priority tasks.

Meta-Meta-Meta Problem Solving

OK, so I'm working on a project and some unexpected bug crops up. It turns out to be a bug in a dependency. I could work around it, but...

I happen to maintain the dependency, so better to fix it at source. Done. Let's set up Travis testing for this dependency too...

Oh no, build fails. Test::Modern won't install on all the versions of Perl I'd hoped it would. (In particular, Perl 5.6.) Why? Turns out some of Test::Modern's dependencies use Module::Build and Module::Build::Tiny, and they require Perl 5.8.

So let's try out Ingy's Alt concept and release alternative distributions of these dependencies which will install cleanly on Perl 5.6. Hence Alt::Test::Warnings::ButEUMM (which led to this) and Alt::Module::Runtime::ButEUMM.

Foster Care

Today I contributed to Scott Walters’ Kickstarter project.  You may have read Scott’s own blog posts on the topic.  Executive precis: for $10,000, Scott will complete work on the latest version of WebGUI, a world-class CMS written in Perl.

I’ll freely admit that I didn’t contribute that much, mainly on account of me not being rich.  As I’m fond of pointing out here, I’m just a regular Joe working-class programmer.  But, at the same time, Perl has been very good to me throughout the years, and I’m not averse to giving a little back when I can.  And, as it happens, right now I can.

The perversity of traditional Perl 5 dereferencing syntax

I wrote this article almost a year ago as part of an omnibus reply to a bunch of different posts from a perl5-porters thread. I never finished all parts of the reply and thus never sent this part either, but in contrast to the other parts of this stillborn mail, I think this one is worth reading. So asked Johan Vromans:

It still escapes me why @* was chosen instead of the much more logical []:

$h{a}[0]->[]

The reason is that there are a number of problems to solve with any new deref syntax:

Non-blocking Mojolicious apps are even easier now!

Hopefully by now you have seen that Mojolicious is a great way to build your non-blocking web (or even non-web) application. Mojolicious come with all kinds of non-blocking functionality out of the box. For more about that see my blog series on the topic. This post is an aside to show you the cool things happening in Mojolicious lately designed to make writing non-blocking apps easier.

Mojolicious is known for fast development and clean APIs. Mojo was that child with lots of excitement and energy, doing new and cool things, providing new and cool functionality, and yes, changing its mind on occasion. But Mojo is growing up and settling down a little bit. It recently went to its first conference and professional training. And it’s starting a family too!

Mojo is starting to feel more grown up, and grown-ups have responsibilities. To borrow one of Perl’s catch phrases, this more mature Mojo knows that it is not good enough anymore to just make things possible, it’s time to make them easy.

Perl Training and donation to TPF

Just a few hours ago Dan Wright mentioned that the Perl 5 Core Maintenance Fund of the The Perl Foundation needs donations. (In addition Makoto Nozaki just mentioned that the budget of the grants committee is only $16,000 for 2014.) Let me offer part of my work as a donation. The deal is that if you organize a Perl Training that I teach, I'll transfer half of the profit to The Perl Foundation. I think it is a 5 x win situation.

  • You win because you get a good training course.
  • Your company that pays the bills wins, because they get a better trained employee.
  • TPF wins because it gets donations.
  • The Perl Community wins by the grants.
  • I win because I can teach and earn some money with something I like to do.
I have the following courses:
  • Beginner Perl
  • Advanced Perl including Moo and Moose
  • Test Automation using Perl
  • Modern Web development with HTML5/CSS3/JS and Perl Dancer

These are all 4-5 days long courses filled with hands-on exercises.

If you'd like to hear more details, please send me an e-mail to gabor@szabgab.com.

Because Sometimes Lightspeed is Too Slow

Spaceballs: Lightspeed is too slow. We'll have to go right to ludicrous speed.

I've pushed Type::Tiny 0.045_03 to CPAN this afternoon. Initial results from CPAN testers seem promising, but if you've got a distribution that uses Type::Tiny it might be worth trying it out with the new version to see if anything breaks. (I don't think anything should!)

The big change in this release is that it adds support for an optional XS backend, which massively boosts the speed of many type constraint checks — especially parameterized types like ArrayRef[InstanceOf["HTTP::Response"]]. The XS backend is a fork of Mouse's type constraints, and needs to be installed separately. It's called Type::Tiny::XS. (OK; not a very creative name.)

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