add error message for ldap requirement

bootstrap/PanicAttack.php

@@ -123,6 +123,21 @@ public function checkAccessRightsEnv()
 		$this->displaySimpleError();
 	}
 
+	/*
+	 |--------------------------------------------------------------------------
+	 | Catch error on missing ldap extension.
+	 |--------------------------------------------------------------------------
+	 | When the ldap extension is not loaded, we display a nice error.
+	 | This is a sanity check to prevent the user from seeing a blank page with an error in the top left
+	*/
+	public function ldap() {
+		$this->title = 'Missing PHP Extension';
+		$this->code = 500;
+		$this->message = 'The PHP extension "ldap" is required but not loaded. Please install and enable it to run Lychee.';
+		$this->displaySimpleError();
+	}
+
+
 	/**
 	 *  dispatcher.
 	 */

public/index.php

@@ -18,6 +18,15 @@
  */
 require_once __DIR__ . '/../bootstrap/PanicAttack.php';
 
+/**
+ * Check if the required extensions are loaded and if not, display a nice error page.
+ * This is a sanity check to prevent the user from seeing a blank page with an error in the top left corner.
+ */
+if (!extension_loaded('ldap')) {
+	$panic_attack = new PanicAttack();
+	$panic_attack->ldap();
+}
+
 /*
  |--------------------------------------------------------------------------
  | Initialize before loading composer