add admin permission config flag

Author: lekoala

_config/debugbar.yml

@@ -47,6 +47,7 @@ LeKoala\DebugBar\DebugBar:
   # set 0 to disable
   template_rendering_warning_level: 2.0
   show_db_warning: true
+  user_admin_only: false
 SilverStripe\Control\Director:
   rules:
     '__debugbar': 'LeKoala\DebugBar\DebugBarController'

code/DebugBar.php

@@ -43,6 +43,7 @@
 use SilverStripe\Config\Collections\DeltaConfigCollection;
 use SilverStripe\Config\Collections\CachedConfigCollection;
 use LeKoala\DebugBar\Bridge\SymfonyMailer\SymfonyMailerCollector;
+use SilverStripe\Security\Permission;
 
 /**
  * A simple helper
@@ -472,6 +473,9 @@ public static function disabledCriteria()
         if (self::isExcludedRoute()) {
             $reasons[] = 'Route excluded';
         }
+        if (self::hasRequiredPermissions()) {
+            $reasons[] = 'Not allowed';
+        }
         return $reasons;
     }
 
@@ -536,6 +540,17 @@ public static function isDisabled()
         return false;
     }
 
+    /**
+     * @return bool
+     */
+    public static function hasRequiredPermissions()
+    {
+        if (static::config()->get('user_admin_only')) {
+            return Permission::check('ADMIN');
+        }
+        return true;
+    }
+
     /**
      * @return bool
      */