How do I autoload PHP classes? - php

Question

I am using classes with Wordpress and I am trying to autoload them in my functions.php file:
spl_autoload_register(function($class) {
include('classes/'.$class.'.php');
});
This is what my classes directory looks like:
classes/
project/
Application.php
Core.php
Site.php
Helpers.php
utils/
Helpers.php
Twig.php
views/
Layout.php
Modules.php
pages/
Home.php
Each class is namespaced based on the directory it is in. For example:
$homeClass = new \views\pages\Home();
When I autoload the classes, I get this error:
PHP Warning: include(classes/project\Application.php): failed to open stream: No such file or directory
Obviously the backslashes that are part of the namespacing don't work in the path. I could update my function to replace the backslashes with forward slashes like this:
spl_autoload_register(function($class) {
include('classes/'.str_replace("\\", "/", $class).'.php');
});
But it seems odd that that would be required. Am I missing something?

Answer 1

I have an example here.
Basically a better version of spl_autoload_register since it only tries to require the class file whenever you initializes the class.
Here it automatically gets every file inside your class folder, requires the files and initializes it. All you have to do, is name the class the same as the file.
index.php
<?php
require_once __DIR__ . '/app/autoload.php';
$loader = new Loader(false);
User::dump(['hello' => 'test']);
autoload.php
<?php
class Loader
{
public static $library;
protected static $classPath = __DIR__ . "/classes/";
protected static $interfacePath = __DIR__ . "/classes/interfaces/";
public function __construct($requireInterface = true)
{
if(!isset(static::$library)) {
// Get all files inside the class folder
foreach(array_map('basename', glob(static::$classPath . "*.php", GLOB_BRACE)) as $classExt) {
// Make sure the class is not already declared
if(!in_array($classExt, get_declared_classes())) {
// Get rid of php extension easily without pathinfo
$classNoExt = substr($classExt, 0, -4);
$file = static::$path . $classExt;
if($requireInterface) {
// Get interface file
$interface = static::$interfacePath . $classExt;
// Check if interface file exists
if(!file_exists($interface)) {
// Throw exception
die("Unable to load interface file: " . $interface);
}
// Require interface
require_once $interface;
//Check if interface is set
if(!interface_exists("Interface" . $classNoExt)) {
// Throw exception
die("Unable to find interface: " . $interface);
}
}
// Require class
require_once $file;
// Check if class file exists
if(class_exists($classNoExt)) {
// Set class // class.container.php
static::$library[$classNoExt] = new $classNoExt();
} else {
// Throw error
die("Unable to load class: " . $classNoExt);
}
}
}
}
}
/*public function get($class)
{
return (in_array($class, get_declared_classes()) ? static::$library[$class] : die("Class <b>{$class}</b> doesn't exist."));
}*/
}
You can easily manage with a bit of coding, to require classes in different folders too. Hopefully this can be of some use to you.

Answer 2

It's not odd at all!
Registering your autoloaders using namespaces as a means to denote a directory structure is fairly common practice. I would recommend following PSR-4 conventions, but if you you're too far in to refactor your naming conventions, then I would recommend using the DIRECTORY_SEPARATOR constant to help PHP decide whether to use '/' or '\', as Windows servers use the latter, and Linux servers use the former.

Answer 3

I've made a class for this requirement, compatible with PSR-4.
You can reach it here:
https://github.com/pablo-pacheco/wp-namespace-autoloader
The explanation is all there but basically it's a composer dependency. You just have to require it in your project:
"require": {
"pablo-pacheco/wp-namespace-autoloader": "dev-master"
}
And then call the class
<?php
new \WP_Namespace_Autoloader( array(
'directory' => __DIR__, // Directory of your project. It can be your theme or plugin. __DIR__ is probably your best bet.
'namespace' => __NAMESPACE__, // Main namespace of your project. E.g My_Project\Admin\Tests should be My_Project. Probably if you just pass the constant __NAMESPACE__ it should work
'classes_dir' => 'src', // (optional). It is where your namespaced classes are located inside your project. If your classes are in the root level, leave this empty. If they are located on 'src' folder, write 'src' here
) );
I appreciate any kind of feedback!

Answer 4

Try this class, it autoloads with or without namespaces