how do I check if a 'Review' has already been written by a given @current_user?
For my model Vendor:
And Each User:
And Each Review:
:belongs_to Vendor :belongs_to User
So. I don't one a User to be able to write more than one Review, so I want to do a check on the vendors/:vendorId URL which is the "show" action, and have a way to make the "Write Review" button disappear or appear based on whether for the @current_user there has already been written a Review for that specific Vendor.
I know the @vendor.id and @loggedin_user.id but not sure how to do a find on two parameters.