array validation for primative datatypes

array validation for hashes

lib/rails_param/param.rb

@@ -12,8 +12,8 @@ module RailsParam
       attr_accessor :params
     end
 
-    def param!(name, type, options = {})
-      name = name.to_s
+    def param!(name, type, options = {}, &block)
+      name = name.to_s unless name.is_a? Integer # keep index for validating elements
 
       return unless params.member?(name) || options[:default].present? || options[:required]
 
@@ -22,11 +22,22 @@ module RailsParam
         params[name] = (options[:default].call if options[:default].respond_to?(:call)) || options[:default] if params[name].nil? and options[:default]
         params[name] = options[:transform].to_proc.call(params[name]) if params[name] and options[:transform]
         validate!(params[name], options)
+
         if block_given?
-          controller = RailsParam::Param::MockController.new
-          controller.params = params[name]
-          yield(controller)
+          if type == Array
+            params[name].each_with_index do |element, i|
+              if element.is_a?(Hash)
+                recurse element, &block
+              else
+                params[name][i] = recurse({ i => element }, i, &block) # supply index as key unless value is hash
+              end
+            end
+          else
+            recurse params[name], &block
+          end
         end
+        params[name]
+
       rescue InvalidParameterError => exception
         exception.param ||= name
         exception.options ||= options
@@ -54,6 +65,13 @@ module RailsParam
 
     private
 
+    def recurse(params, index = nil)
+      raise InvalidParameterError, 'no block given' unless block_given?
+      controller = RailsParam::Param::MockController.new
+      controller.params = params
+      yield(controller, index)
+    end
+
     def coerce(param, type, options = {})
       begin
         return nil if param.nil?

spec/rails_param/param_spec.rb

@@ -192,6 +192,32 @@ describe RailsParam::Param do
       end
     end
 
+    describe 'validating array elements' do
+      it 'typecasts array elements' do
+        allow(controller).to receive(:params).and_return({'array' => ['1', '2']})
+        controller.param! :array, Array do |a, i|
+          a.param! i, Integer, required: true
+        end
+        expect(controller.params['array'][0]).to be_a Integer
+        expect(controller.params['array'][1]).to be_a Integer
+      end
+
+      it 'validates array of hashes' do
+        params = {'array' => [{'object'=>{ 'num' => '1', 'float' => '1.5' }},{'object'=>{ 'num' => '2', 'float' => '2.3' }}] }
+        allow(controller).to receive(:params).and_return(params)
+        controller.param! :array, Array do |a|
+          a.param! :object, Hash do |h|
+            h.param! :num, Integer, required: true
+            h.param! :float, Float, required: true
+          end
+        end
+        expect(controller.params['array'][0]['object']['num']).to be_a Integer
+        expect(controller.params['array'][0]['object']['float']).to be_instance_of Float
+        expect(controller.params['array'][1]['object']['num']).to be_a Integer
+        expect(controller.params['array'][1]['object']['float']).to be_instance_of Float
+      end
+    end
+
     describe "validation" do
       describe "required parameter" do
         it "succeeds" do