I have a big problem here. In my rails 3.0.9 app I have a model
"invoice" that model "accepts nested attributes" for "invoice
details". So, I don't have a "controller" nor "views" for "invoice
details", just model, because I have a "partial" in "invoices views"
for the "nested attributes".
The thing is that I need to run a custom validation when every
"invoice details" is created, and I need a variable stored in
"session". But Models can not access "session" variables.
So I want to know, how can I access that variable and then use it in