craft/web/ErrorHandler::renderException re-add left attributes from Yii2 or add an event to add those

[Anubarak]

I usually control my REST Application states via Exceptions. In Craft 3 Yii2 did everything for me.
When I throw certain Exceptions, I was able to tell the user the exact reason why something has failed in JS. Craft 4 unfortunately removed that option unless I overwrite your ErrorHandler with the one from Yii2 again.

For example in my Controller

$i = $this->request->getBodyParam('someParam');
if($i === 0){
    throw new HttpException(400, 'i must not be 0', 1);
}

if($i > 10){
  throw new HttpException(400, 'i must not be larger than 10', 2);
}

the responses would then be like

{
    name:  'Bad Request',
    message: 'i must not be 0' | 'i must not be larger than 10',
    status: 400,
    code: 0 | 1
}

I was able to check

// display the error message
if (res.code === 0) {
   // do something special, like prepare a new request with the better value instantly
}
// and so on

However: Craft 4 does only this in a live environment

{
    name:  'Bad Request',
    message: 'Bad Request'
}

This one doesn't contain any useful information at all and a totally different response in dev mode.

It would be awesome if there was an event for us so I can easily overwrite your response with the one from Yii2 again without the requirement to overwrite the entire class again. In a perfect world you would just call Yii2 convertExceptionToArray to have all relevant information in all application states.

Even more problematic now: depending of the response header, totally different data is passed... In Yii2 the structural exception response was always the same. Craft 4 shows a detailed response in case of an XML request and basically nothing in case of JSON. (To avoid confusions: I frequently use https://www.yiiframework.com/doc/api/2.0/yii-filters-contentnegotiator and it's a requirement for me provide different response types for different API users)

[brandonkelly]

This actually changed back in Craft 3.6 (5775433).

I’ve just updated the code for the next Craft 3 and 4 releases, so all JSON error responses start including name and code keys, and status for HttpExceptions regardless of Dev Mode, just like Yii does out of the box. (48b7ead)

[Anubarak]

Yeah you are right - I didn't use the latest Craft 3 versions because I always need to inspect each commit due to these reasons 😅
However this time around we skipped 3.6.15 directly to Craft 4 in order to safe some time.

As always I highly appreciate your incredible fast reaction. Your support is always on top 👍

[brandonkelly]

Craft 3.7.52 and 4.2.2 are out now with that change.