Recording fields and parsing errors when Json data guard is used

[SSeanin]

By using Form<Contextual<'_, T>> some errors could be returned from FromFormField impl in types deriving FromForm. These errors could be handled in the route handler by using context.

Is there a similar feature when using Json<T> as a data guard?

[the10thWiz]

Your best option is probably Result<Json<T>, Error>, which will report the errors in json parsing if it couldn't be parsed.

[SSeanin]

I actually ended up manually collecting the errors in a from conversion and forwarding them in the handler. This triggers another conversion between error types which could be handled. Different errors could be returned from handlers this way.