Re: [Xoops-development] addressing "blank page" problem

[K. O. <web...@my...>]

> Or maybe this:  Leave the error handler always ON.  If debug mode is on,
> show all errors and warnings (native PHP messages AND explicitly
> 'triggered' messages).  If debug mode is off, show only 'triggered'
> messages.  If we use trigger_error very sparingly (or E_USER_ERROR for
> errors-to-be-displayed) then the end user will only see a message if
> something goes very wrong (e.g. can't connect to database), which may be
> useful to alert the site administrator.  (In a custom error handler you
> can strip out any path info so this is not a security risk.)

I like this idea.. Maybe we can wrap the trigger_error() function with a
custom function/class so that we
 can always call the custom trigger error function/method within the codes
which does
not always call the native trigger_error function. This way, the coders
wouldn't need to
think about whether to use the native trigger_error() function in certain
areas of their
codes but just always use the custom one wherever something wrong might
happen.

For example,


class ErrorHandler
{

 function ErrorHandler()
 {
  set_error_handler(array(&$this, 'trigger'));
 }

 function trigger($errno, $errstr, $errfile, $errline)
 {
  switch ($errno) {
    case E_USER_ERROR:
      // do something here
      break;
    case E_USER_WARNING:
      // do something here
      break;
    case E_USER_NOTICE:
      // do something here
      break;
    default:
      // do something here
      break;
  }

 }

// A class that triggers all errors
class ShowAllErrorHandler extends ErrorHandler
{

 function notice($msg)
 {
  trigger_error(E_USER_NOTICE, $msg);
 }

 function warning($msg)
 {
  trigger_error(E_USER_WARNING, $msg);
 }

 function fatal($msg)
 {
  trigger_error(E_USER_ERROR, $msg);
 }
}

// A class that triggers only fatal-level errors
class FatalErrorHandler extends ErrorHandler
{
 function notice($msg)
 {
  // do nothing
 }

 function warning($msg)
 {
  // do nothing
 }

 function fatal($msg)
 {
  trigger_error(E_USER_ERROR, $msg);
 }
}


And at startup, we can use a factory method/class to create one of the error
handler classes
depending on a config setting or the user level (admin, anonymous, etc).

$debug_level = $xoopsUser->isAdmin() ? XOOPS_DEBUG_SHOWALL :
$config['debug_level'];
$error_handler =& ErrorHandler::getInstance($debug_level);
...
$error_handler->notice('A notice error');
...