lib/hydra/validations/cardinality.rb in hydra-validations-0.3.2 vs lib/hydra/validations/cardinality.rb in hydra-validations-0.4.0

@@ -1,20 +1,57 @@
+require 'active_support/core_ext/array/wrap'
+
 module Hydra
   module Validations
     #
-    # Cardinality - a mixin adding cardinality validation methods.
+    # CardinalityValidator - A cardinality validator for enumerable values based on
+    # ActiveModel's LengthValidator.
     #
-    module Cardinality
+    # validates :field, cardinality: { minimum: 1, maximum: 5 }
+    # validates :field, cardinality: { in: 1..5 }
+    # validates :field, cardinality: { within: 1..5 }
+    # validates :field, cardinality: { is: 1 }
+    #
+    # See ActiveModel::Validations::LengthValidator for options.
+    #
+    class CardinalityValidator < ActiveModel::Validations::LengthValidator
 
-      def validate_cardinality(cardinality, record, attribute, value)
-        return validate_single_cardinality(record, attribute, value) if cardinality == :single
-        raise ArgumentError, "Cardinality validation not supported: #{cardinality.inspect}"
+      def initialize(options = {})
+        super(default_options.merge(options))
       end
 
-      def validate_single_cardinality(record, attribute, value)
-        # TODO i18n message
-        record.errors.add(attribute, "can't have more than one value") if value.respond_to?(:each) && value.size > 1
+      def validate_each(record, attribute, value)
+        return if options[:allow_empty] && value.respond_to?(:empty?) && value.empty?
+        super
       end
 
+      protected
+
+      def default_options
+        { wrong_length: "has the wrong cardinality (should have %{count} value(s))", 
+          too_short: "has too few values (minimum cardinality is %{count})", 
+          too_long: "has too many values (maximum cardinality is %{count})"
+        }
+      end
+
+      private 
+
+      # Override
+      def tokenize(value)
+        Array.wrap(value)
+      end
+
     end
+
+    module HelperMethods
+      def validates_cardinality_of *attr_names
+        validates_with CardinalityValidator, _merge_attributes(attr_names)
+      end
+
+      def validates_single_cardinality_of *attr_names
+        options = _merge_attributes(attr_names).merge(is: 1)
+        validates_with CardinalityValidator, options
+      end
+    end
+
   end
 end