PHP: How to get all classes when using autoloader

Question

I'm using composer to generate autoloader:

"autoload": {
  "psr-4": {
    "SomeNamespace\\": "src/SomeDir"
  }
}

I need to create instances of all classes that implement specific interface. It's fairly easy when not using autoloader, however get_declared_classes() is not playing well with autoloaders. It will list a class only after it was instantiated with autoloader.

Answer 1

You can use dirty hack and require_once all classes before get_declared_classes() function call.

1. At first do dump all classes to class map via composer dumpautoload --optimize
2. Now you can fetch composer loader and require all files

    $res = get_declared_classes();
    $autoloaderClassName = '';
    foreach ( $res as $className) {
        if (strpos($className, 'ComposerAutoloaderInit') === 0) {
            $autoloaderClassName = $className; // ComposerAutoloaderInit323a579f2019d15e328dd7fec58d8284 for me
            break;
        }
    }
    $classLoader = $autoloaderClassName::getLoader();
    foreach ($classLoader->getClassMap() as $path) {
        require_once $path;
    }

3. Now you can easy use get_declared_classes() again, which return all classes the composer knowns

P.S. Don't use it in production.