[5.x] replace 404 and 406 CRITICAL errors with NOTICE and useful information (joomla#46296)

Author: MarcelSchuermann

libraries/src/Exception/ExceptionHandler.php

@@ -10,10 +10,13 @@
 namespace Joomla\CMS\Exception;
 
 use Joomla\CMS\Application\CMSApplication;
+use Joomla\CMS\Application\Exception\NotAcceptable;
 use Joomla\CMS\Error\AbstractRenderer;
 use Joomla\CMS\Event\Application\AfterInitialiseDocumentEvent;
 use Joomla\CMS\Factory;
 use Joomla\CMS\Log\Log;
+use Joomla\CMS\Router\Exception\RouteNotFoundException;
+use Joomla\CMS\Uri\Uri;
 
 // phpcs:disable PSR1.Files.SideEffects
 \defined('_JEXEC') or die;
@@ -221,18 +224,38 @@ protected static function isException($error)
      */
     protected static function logException(\Throwable $error)
     {
+        // Handle common client errors as notices instead of critical errors
+        if ($error instanceof RouteNotFoundException) {
+            $level   = Log::NOTICE;
+            $message = \sprintf(
+                'Page not found (404): %s. Message: "%s"',
+                Uri::getInstance()->toString(),
+                $error->getMessage()
+            );
+            $category = 'client-error';
+        } elseif ($error instanceof NotAcceptable) {
+            $level   = Log::NOTICE;
+            $message = \sprintf(
+                'Not acceptable (406): %s. Message: "%s"',
+                Uri::getInstance()->toString(),
+                $error->getMessage()
+            );
+            $category = 'client-error';
+        } else {
+            // For all other errors, log a critical error with the full stack trace.
+            $level   = Log::CRITICAL;
+            $message = \sprintf(
+                'Uncaught Throwable of type %1$s thrown with message "%2$s". Stack trace: %3$s',
+                \get_class($error),
+                $error->getMessage(),
+                $error->getTraceAsString()
+            );
+            $category = 'error';
+        }
+
         // Try to log the error, but don't let the logging cause a fatal error
         try {
-            Log::add(
-                \sprintf(
-                    'Uncaught Throwable of type %1$s thrown with message "%2$s". Stack trace: %3$s',
-                    \get_class($error),
-                    $error->getMessage(),
-                    $error->getTraceAsString()
-                ),
-                Log::CRITICAL,
-                'error'
-            );
+            Log::add($message, $level, $category);
         } catch (\Throwable) {
             // Logging failed, don't make a stink about it though
         }