Added option enable-event-dispatcher to initialize EventDispatcher for command. (#2420)

* Added trait EnableEventDispatcher for command.

* Update CHANGELOG-2.0.md

Author: limingxinleo

src/Command.php

@@ -27,6 +27,8 @@
 
 abstract class Command extends SymfonyCommand
 {
+    use EnableEventDispatcher;
+
     /**
      * The name of the command.
      *
@@ -421,10 +423,13 @@ protected function configure()
         if (! isset($this->signature)) {
             $this->specifyParameters();
         }
+
+        $this->addEnableDispatcherOption();
     }
 
     protected function execute(InputInterface $input, OutputInterface $output)
     {
+        $this->enableDispatcher($input);
         $callback = function () {
             try {
                 $this->eventDispatcher && $this->eventDispatcher->dispatch(new Event\BeforeHandle($this));

src/EnableEventDispatcher.php

@@ -0,0 +1,32 @@
+<?php
+
+declare(strict_types=1);
+/**
+ * This file is part of Hyperf.
+ *
+ * @link     https://www.hyperf.io
+ * @document https://hyperf.wiki
+ * @contact  group@hyperf.io
+ * @license  https://github.com/hyperf/hyperf/blob/master/LICENSE
+ */
+namespace Hyperf\Command;
+
+use Hyperf\Utils\ApplicationContext;
+use Psr\EventDispatcher\EventDispatcherInterface;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+
+trait EnableEventDispatcher
+{
+    public function addEnableDispatcherOption()
+    {
+        $this->addOption('enable-event-dispatcher', null, InputOption::VALUE_NONE, 'Whether enable event dispatcher.');
+    }
+
+    public function enableDispatcher(InputInterface $input)
+    {
+        if ($input->getOption('enable-event-dispatcher')) {
+            $this->eventDispatcher = ApplicationContext::getContainer()->get(EventDispatcherInterface::class);
+        }
+    }
+}