couchrest_model/lib/couchrest/model/validations/uniqueness.rb
2010-06-23 11:58:35 +02:00

45 lines
1.3 KiB
Ruby

# encoding: utf-8
module CouchRest
module Model
module Validations
# Validates if a field is unique
class UniquenessValidator < ActiveModel::EachValidator
# Ensure we have a class available so we can check for a usable view
# or add one if necessary.
def setup(klass)
@klass = klass
end
def validate_each(document, attribute, value)
view_name = options[:view].nil? ? "by_#{attribute}" : options[:view]
# Determine the base of the search
base = options[:proxy].nil? ? @klass : document.instance_eval(options[:proxy])
if base.respond_to?(:has_view?) && !base.has_view?(view_name)
raise "View #{document.class.name}.#{options[:view]} does not exist!" unless options[:view].nil?
@klass.view_by attribute
end
docs = base.view(view_name, :key => value, :limit => 2, :include_docs => false)['rows']
return if docs.empty?
unless document.new?
return if docs.find{|doc| doc['id'] == document.id}
end
if docs.length > 0
document.errors.add(attribute, :taken, :default => options[:message], :value => value)
end
end
end
end
end
end