[COMMAND][EVENTS] Added command to list events and handlers, and search by regex

src/Command/ListEventsCommand.php

@@ -0,0 +1,53 @@
+<?php
+
+namespace App\Command;
+
+use Functional as F;
+use Symfony\Bundle\FrameworkBundle\Command\EventDispatcherDebugCommand;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use Symfony\Component\EventDispatcher\EventDispatcherInterface;
+
+class ListEventsCommand extends EventDispatcherDebugCommand
+{
+    protected static $defaultName = 'app:events';
+    private EventDispatcherInterface $dispatcher;
+
+    public function __construct(EventDispatcherInterface $dispatcher)
+    {
+        parent::__construct($dispatcher);
+        $this->dispatcher = $dispatcher;
+    }
+
+    protected function configure()
+    {
+        $this->setDefinition([new InputArgument('pattern',
+                                                InputArgument::OPTIONAL,
+                                                'An event pattern to look for')])
+             ->setDescription('Search for an event');
+    }
+
+    protected function execute(InputInterface $input, OutputInterface $output): int
+    {
+        $io = new SymfonyStyle($input, $output);
+
+        $options   = [];
+        $patterm   = $input->getArgument('pattern') ?? 'GNUsocial.*';
+        $listeners = $this->dispatcher->getListeners();
+        $listeners = F\select($listeners,
+                              function ($_, $key, $__) use ($patterm) {
+                                  return preg_match('/' . $patterm . '/', $key);
+                              });
+
+        foreach ($listeners as $event => $listener) {
+            echo 'Event \'' . $event . "\\' handled by:\n";
+            foreach ($listener as $c) {
+                $r = new \ReflectionFunction($c);
+                echo '    ' . get_class($r->getStaticVariables()['handler'][0]) . "\n";
+            }
+        }
+        return 0;
+    }
+}