Examples Archives

Mojolicious: Do It For The Candy!

Most of my recent blog posts about Mojolicious have revolved around its non-blocking capabilities. I like to write about those because I think that it is those capabilities that can bring new eyes to Perl from other languages, much like Node.js brought eyes to server-side javascript (for the same reason). That said, lately I have had excuses to show off Mojolicious and when I have done so, it has been some of the other cool features that have garnered the “Ooooh”s and “Aaaah”s from onlookers.

In this article I will show you some of those extras, like accessing your generated pages and even app itself direcly from the command line. I will also show how testing can be easy, powerful, expressive and yet still readably beautiful.

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.

Writing Non-Blocking Applications with Mojolicious: Part 3

This the the third part in an on-going series about using Mojolicious to write non-blockging applications (with an eye towards the web, obviously). In part 1 I demonstrated the how it can improve the number of requests/clients served when the application uses high-latency backends (in that case a database). In part 2 I showed how each request can be sped up when that request needs multiple resources from a high-latency service (e.g. external web services).

In each, I showed a blocking example, then a non-blocking example. I then gave the usual warning that you had to use a Mojolicious server for the nonblocking version. While its true that you need a Mojolicious server to get the benefits of the nonblocking architecture, in this post I will show how with a little care in construction, you can build your application so that it will run correctly on any supported server and the nonblocking benefits will be evident where possible.

Writing Non-Blocking Applications with Mojolicious: Part 2

Last time, I showed you how to write non-blocking (web) applications using Mojolicious. In those examples, each action only had to perform one non-blocking action. In this article I’m going to take things a little further, introducing you to Mojo::IOLoop::Delay. I will use a delay object to perform multiple simultaneous non-blocking actions and wait until they complete before moving on, all without blocking the server for other requests.

Writing Non-Blocking Applications with Mojolicious: Part 1

One question I often hear is “Why should I chose Mojolicious versus one of the other major Perl web frameworks?” While I have many answers to that question, I personally believe the most important difference is that Mojolicious is designed to be non-blocking. Many of you will have heard of Node.js. The reason that Node is popular is that it is designed to be non-blocking. By writing your webapp in a non-blocking style using a non-blocking framework, you can often build a faster and smarter application, requiring fewer servers to handle the same amount of traffic. Although Perl has several web frameworks, only one was written with non-blocking design in mind: Mojolicious.

To demonstrate a non-blocking application, I am going to write a simple pastebin using Mojolcious and Mango, a non-blocking MongoDB library (from the same developers as Mojo).

Some code ports to Mojolicious, just for fun.

Today is a relatively minor holiday in the US, but I had work off all the same. I found myself experimenting (when I probably should have been working on my YAPC::Brazil talk :-/). Thanks to today’s PerlWeekly (you are a subscriber right??), I found out about an interesting post by Johnny Moreno which creates a tiny json service backend using Perl. Of course it uses CGI.pm to do so, which made me curious what a Mojolcious port would look like.

My "Mojolicious Introduction" now updated for 4.0

On Feb 28, 2013 I gave a talk to Chicago.pm about Mojolicious. I called it an introduction, but I really wanted to show some of the features that sets Mojolicious apart. Because of this, the talk moves very fast. It hits routing and responses quickly, hits testing often, on all the way to well-tested non-blocking websocket examples.

I promised to get my slides up afterwards but life (i.e. my doctoral thesis) got in the way. Now with the release of Mojolicious 4.0 I thought I would take the opportunity to right a wrong and get the slides up; so here they are: http://mojolicious-introduction.herokuapp.com/!

The talk is itself a Mojolicious app, the source of which is available from on GitHub. Not only are all the code snippets shown in the talk included, not only do they all run, but they are actually what is rendered by the talk (DRY++), so what you see is what you get! Please leave any feedback and ask any questions. I may not see the responses here, so feel free to ping me elsewhere if needed.

Thank you Ack!

People may have noticed my absence from the Perl world lately. I have been writing my Ph.D. thesis (179 pages on Ultrafast Electron Microscopy with my Physics::UEMColumn Perl module featured) and defense.

Ack is a tool for searching code and text. It works much like the unix tool grep, although it is imbued with the power of Perl. To mark the release of Ack 2.0 though I wanted to mention a few one-liners that made my life easier in this stressful time.

My thesis is written in many LaTeX files and one can probably imagine that searching those files was needed regularly. The biggest is for finding non-ascii characters. As I add content from old publications or external programs, lots of non-ascii characters can often come along for the ride. LaTeX is a very old program, well pre-dating unicode, and it has a very different way of adding special characters with its own markup. In fact parts of the compiling toolchain croak with unicode characters. So I found myself using

ack '[^[:ascii:]]'

regularly. Also I had to keep a list of all the abbreviations that I had used in the paper, but of course you forget if you have them all. I used this little bash-ack conglomeration to find all sequences of two or more upper-case characters, which is how I write my abbreviations,

ack -ho '\p{Upper}{2,}' | sort | uniq

I’m sure I used many other little ackings here and there, but these were the two I could remember off-hand. Thanks to Andy and everyone who has contributed to ack!

Now go use it to make your life easier!

Visit the new site: beyondgrep.com

A WebSocket Mojolicious/DBI Example

Building on my (second) example from my recent post A Simple Mojolicious/DBI Example, I thought I would take it just a little bit futher. One of my favorite features of Mojolicious is that it comes with WebSockets out of the box! In this example I show how you can take the example script and allow it to run without refreshing the window.

A Simple Mojolicious/DBI Example

A friend of mine is learning database administration, but for the first time needs to connect it to a webapp. Having done most of his work in MS Access, he has no idea what a web framework is, nor how one would connect a database to it. To help him learn I wrote up a little application using Mojolicious and SQLite.

About Joel Berger

user-pic As I delve into the deeper Perl magic I like to share what I can.