Hey I have a rather complex record set with lots of associated models all being save by 1 form. So I've wrapped the whole thing in a transaction block, but, does anyone know how I can get Active Record to return my validation errors?
Hey Cammo,
This may not be straight forward and it depends on how your transaction is setup. If you are creating the objects during the transaction, it will only process the entities until it fails, potentially leaving some objects uninstantiated.
AR errors are attached to the AR instance when it is checked for validation. So save, create, valid? calls will all run through the validation steps of a model and attach any errors that were found to that instance.
ie.
@my_model.valid? #=> will attach the errors to the @my_model instance.
You get these with a number of methods
@my_model.errors
or in a view
error_messages_for ‘my_model’
If you want to get all the objects to return their errors you might use something like this in your controller. (sorry can’t check syntax here )
def create
@my_objects = list_of_object_params.map{ |obj_p| MyModel.new( obj_p ) }
MyObject.transaction do
@my_objects.each{ |obj| obj.save! }
end
rescue
#There is an issue in the transaction here.
@my_objects.each{ |obj| obj.valid? } #=> ensure validation is run on all objects
render / redirect / whatever
end
then in your view
<% @my_objects.each do |obj| %>
<% @tmp = obj %>
<%= error_messages_for ‘tmp’ %>
<% end %>
This may not work, it’s not very elegant, and I’ve never tried it
before 
But it may give you some clues to move forward.
Cheers
Daniel
Yeah cool. It's kinda a shortcoming of transactions, I can see why it works that way, but it seems a little stupid.
Thanks again, I'll investigate.