Monday, 24 June 2013

The dawn of the combining robots

Yesterday I wanted to say a lot of things about Dancer2 and Apps, but I was a bit sleepy, so I keep the discussion on simple topics. Now I want to talk about something I experienced in the passage from Dancer 1 to Dancer 2 and how it fooled me.

When I started using Dancer 1 I was a young (well, younger than now) and I did dirty things, as young people do. Things like putting Dancer routes directly in the bin/ script.
Talking about Dancer 1 this is not a really dirty thing, Dancer 1 declarations are always global so the problem is just "esthetic".

Routes under lib directory, in a perl module, give a feeling of tidiness, nothing more.

Problem is that, working this way, you start thinking about bin/ as your app, as the center of your site. This is a lot confusing when Dancer2 come along.

You should think about bin/ as just your "launcher", keeping it as empty as you can, using it just to configure what code you want to load in your site.

The dancer2 init script will not help you thinking this way. Launching it you'll have:
  • bin/ with import Dancer2 
  • lib/ with just import Dancer2 :syntax 
What does this mean? It means you're working just with one app, declared in the bin/ and all the code you'll write in pm files will be referred to it. This app will have name "main" and your design will start in a not-so-modular way.

Evil evil Dancer2 init, wanting to keep developers in the Dancer1 global world, hiding the great powers of Dancer2 Apps!

What should you do? In my opinion you should leave import Dancer in the bin/ (you can't make webapp start without it), but you should also use import Dancer in your lib/ files. Files, yes, more than one, because you should split up functionality (and navigation) in more than one perl module.

Then, your bin/ will become:

import Dancer2 #a "main" app will still be created
import APP1 #some routes and logic
import APP2 #different routes and logic
and so on...

This way, just commentig one line (or uncommenting another) you can turn on/off features, behaviours, navigations and the global structure of your site is easy to understand.

A little thing to close the post. Try sometimes to launch your developement server this way:
Bootstrap will give you notifications about th Apps start. Here you'll see site structure in a very clean way, something the code itself can't do.

No comments:

Post a Comment