I am building a framework that will validate forms both client-side (javascript) and server-side based on a form requirements specification written in json.

The purpose is to get rid of logically equivalent code on the server and client to make the code more maintainable, faster to write, and less buggy.

The specification format may look something like:

{ '<field_name>' : ['<validation_function>', 'req', ['<requirement>', <param>], ...], ... }

( the requirement list is ordered so that the user can get most basic error messages first, the 'req' requirement must come first if it exists and means that the field is required)

e.g.)

{
    'name' : ['string', 'req', ['min',6], ['max',150], ['match', /^[\sa-z0-9ÅÄÖåäö&]$/i], ['not_match', /^tmp_/]],
    'email' : ['email', 'req'],
    'email_confirm' : ['same_as', 'email'],
    'password' : ['string', 'req', ['min', 6], ['max', 64], ['match', /^[a-z0-9\!@#\$%^&*_+.]$/i] ],
}

Does anyone know of a similar technology? I think the Rails validation framework solves the problem on the wrong level because I have found that forms often operate on more than one model.