DiscoverEvents.php

TLDR

This file contains the DiscoverEvents class with several methods for discovering events and listeners in a listener directory.

Methods

within

This method takes a listener directory path and a base path as parameters and returns an array containing all the discovered events and their corresponding listeners.

getListenerEvents

This method takes an iterable of listeners and the base path as parameters and returns an array of the listeners with their corresponding events.

classFromFile

This method takes a SplFileInfo object and the base path as parameters and returns the class name extracted from the given file path.

guessClassNamesUsing

This method takes a callback function as a parameter and sets it as the callback to be used for guessing class names.

Classes

None

<?php

namespace Illuminate\Foundation\Events;

use Illuminate\Support\Reflector;
use Illuminate\Support\Str;
use ReflectionClass;
use ReflectionException;
use ReflectionMethod;
use SplFileInfo;
use Symfony\Component\Finder\Finder;

class DiscoverEvents
{
    /**
     * The callback to be used to guess class names.
     *
     * @var callable(SplFileInfo, string): string|null
     */
    public static $guessClassNamesUsingCallback;

    /**
     * Get all of the events and listeners by searching the given listener directory.
     *
     * @param  string  $listenerPath
     * @param  string  $basePath
     * @return array
     */
    public static function within($listenerPath, $basePath)
    {
        $listeners = collect(static::getListenerEvents(
            (new Finder)->files()->in($listenerPath), $basePath
        ));

        $discoveredEvents = [];

        foreach ($listeners as $listener => $events) {
            foreach ($events as $event) {
                if (! isset($discoveredEvents[$event])) {
                    $discoveredEvents[$event] = [];
                }

                $discoveredEvents[$event][] = $listener;
            }
        }

        return $discoveredEvents;
    }

    /**
     * Get all of the listeners and their corresponding events.
     *
     * @param  iterable  $listeners
     * @param  string  $basePath
     * @return array
     */
    protected static function getListenerEvents($listeners, $basePath)
    {
        $listenerEvents = [];

        foreach ($listeners as $listener) {
            try {
                $listener = new ReflectionClass(
                    static::classFromFile($listener, $basePath)
                );
            } catch (ReflectionException) {
                continue;
            }

            if (! $listener->isInstantiable()) {
                continue;
            }

            foreach ($listener->getMethods(ReflectionMethod::IS_PUBLIC) as $method) {
                if ((! Str::is('handle*', $method->name) && ! Str::is('__invoke', $method->name)) ||
                    ! isset($method->getParameters()[0])) {
                    continue;
                }

                $listenerEvents[$listener->name.'@'.$method->name] =
                                Reflector::getParameterClassNames($method->getParameters()[0]);
            }
        }

        return array_filter($listenerEvents);
    }

    /**
     * Extract the class name from the given file path.
     *
     * @param  \SplFileInfo  $file
     * @param  string  $basePath
     * @return string
     */
    protected static function classFromFile(SplFileInfo $file, $basePath)
    {
        if (static::$guessClassNamesUsingCallback) {
            return call_user_func(static::$guessClassNamesUsingCallback, $file, $basePath);
        }

        $class = trim(Str::replaceFirst($basePath, '', $file->getRealPath()), DIRECTORY_SEPARATOR);

        return str_replace(
            [DIRECTORY_SEPARATOR, ucfirst(basename(app()->path())).'\\'],
            ['\\', app()->getNamespace()],
            ucfirst(Str::replaceLast('.php', '', $class))
        );
    }

    /**
     * Specify a callback to be used to guess class names.
     *
     * @param  callable(SplFileInfo, string): string  $callback
     * @return void
     */
    public static function guessClassNamesUsing(callable $callback)
    {
        static::$guessClassNamesUsingCallback = $callback;
    }
}