Skip to content

Latest commit

 

History

History
47 lines (27 loc) · 2.81 KB

15_Cascading_file_system.md

File metadata and controls

47 lines (27 loc) · 2.81 KB

This framework uses a cascading file system. This system is similar to CSS (Cascading Style Sheets) where style properties can overwrite one another based on the hierarchy in which they're called.

This means that there are several aspects of your application that can be set on either A) The app level or B) the core level. The system always checks on the app level first, and if it doesn't find what it's looking for there, it will check the core level.

configs.php is a good example of the cascading file system at work. In the last section, you edited your app level config file, but if you look in /core/configs/config.php you'll also see a series of configs, all which can be overwritten at the app level.

For example, the following line in core config says that if TIME_FORMAT is not already defined it should be F j, Y g:ia

if(!defined('TIME_FORMAT')) define('TIME_FORMAT', 'F j, Y g:ia');

If you wanted to overwrite this, for example, to make the default time format be Y-m-d you could set this in your app level config:

define('TIME_FORMAT', 'Y-m-d');

Be sure to check core config for a full list of configurations you may wish to override.

Cascading Controllers and Libraries

In addition to configs, Controllers and Libraries also cascade.

This means if you request a controller called foobar (http://localhost/foobar), the framework would first check for /app/controllers/c_foobar.php and then, if it didn't find it there, /core/controllers/c_foobar.php.

The same can be said for libraries. If you call a library Foobar it would look first for /app/libraries/Foobar.php and then, if it didn't find it there, /core/libraries/Foobar.php.

Shared / Vendors

Occasionally you may wish to include an external PHP class in your projects that you've found online. It's also possible that you may want this same class accessible to more than one app you're working on.

To make this possible, create a /shared/vendors/ directory parallel to core and your apps. Within this vendors directory, place your class within its own directory:

root/
	core/
	environment.php
	p1.yourdomain.com
	p2.yourdomain.com
	shared/vendors/ClassName/ClassName.php

Important: the directory and class name must match in order for autoloading to work.

(FYI) How does the cascading file system work?

The cascading file system is powered by the File class (/core/libraries/File.php) which specifies all the levels (app, core, shared) the the framework should check when looking for configs, controllers or libraries.

Auto-loading Libraries, specifically, is powered by the autoloader() method within File.

And what triggers autoloader()? This brings us back to bootstrap.php, specifically this line which delegates PHP auto loading to File's autoload() method:

spl_autoload_register(array('File', 'autoloader'));