Allow validation of nested parameters.

CHANGELOG.markdown

@@ -1,6 +1,7 @@
 Next Release
 ============
 
+* [#236](https://github.com/intridea/grape/pull/236): Allow validation of nested parameters. - [@tim-vandecasteele](https://github.com/tim-vandecasteele).
 * [#201](https://github.com/intridea/grape/pull/201): Added custom exceptions to Grape. Updated validations to use ValidationError that can be rescued. - [@adamgotterer](https://github.com/adamgotterer).
 * [#211](https://github.com/intridea/grape/pull/211): Updates to validation and coercion: Fix #211 and force order of operations for presence and coercion - [@adamgotterer](https://github.com/adamgotterer).
 * [#210](https://github.com/intridea/grape/pull/210): Fix: `Endpoint#body_params` causing undefined method 'size' - [@adamgotterer](https://github.com/adamgotterer).

README.markdown

@@ -220,6 +220,11 @@ You can define validations and coercion options for your parameters using `param
 params do
   requires :id, type: Integer
   optional :name, type: String, regexp: /^[a-z]+$/
+
+  group :user do
+    requires :first_name
+    requires :last_name
+  end
 end
 get ':id' do
   # params[:id] is an Integer
@@ -229,6 +234,9 @@ end
 When a type is specified an implicit validation is done after the coercion to ensure 
 the output type is the one declared.
 
+Parameters can be nested using `group`. In the above example, this means both
+`params[:user][:first_name]` and `params[:user][:last_name]` are required next to `params[:id]`.
+
 ### Namespace Validation and Coercion
 Namespaces allow parameter definitions and apply to every method within the namespace.
 

lib/grape/validations.rb

@@ -8,16 +8,19 @@ module Validations
     # All validators must inherit from this class.
     # 
     class Validator
-      def initialize(attrs, options, required)
+      def initialize(attrs, options, required, scope)
         @attrs = Array(attrs)
         @required = required
+        @scope = scope
 
         if options.is_a?(Hash) && !options.empty?
           raise "unknown options: #{options.keys}"
         end
       end
 
       def validate!(params)
+        params = @scope.params(params)
+
         @attrs.each do |attr_name|
           if @required || params.has_key?(attr_name)
             validate_param!(attr_name, params)
@@ -40,7 +43,7 @@ def self.convert_to_short_name(klass)
     ##
     # Base class for all validators taking only one param.
     class SingleOptionValidator < Validator
-      def initialize(attrs, options, required)
+      def initialize(attrs, options, required, scope)
         @option = options
         super
       end
@@ -67,7 +70,11 @@ def self.register_validator(short_name, klass)
     end
 
     class ParamsScope
-      def initialize(api, &block)
+      attr_accessor :element, :parent
+
+      def initialize(api, element, parent, &block)
+        @element = element
+        @parent = parent
         @api = api
         instance_eval(&block)
       end
@@ -89,7 +96,22 @@ def optional(*attrs)
 
         validates(attrs, validations)
       end
-
+
+      def group(element, &block)
+        scope = ParamsScope.new(@api, element, self, &block)
+      end
+
+      def params(params)
+        params = @parent.params(params) if @parent
+        params = params[@element] || {} if @element
+        params
+      end
+
+      def full_name(name)
+        return "#{@parent.full_name(@element)}[#{name}]" if @parent
+        name.to_s
+      end
+
     private
       def validates(attrs, validations)
         doc_attrs = { :required => validations.keys.include?(:presence) }
@@ -106,9 +128,10 @@ def validates(attrs, validations)
         if desc = validations.delete(:desc)
           doc_attrs[:desc] = desc
         end
-
-        @api.document_attribute(attrs, doc_attrs)
-
+
+        full_attrs = attrs.collect{ |name| { :name => name, :full_name => full_name(name)} }
+        @api.document_attribute(full_attrs, doc_attrs)
+
         # Validate for presence before any other validators
         if validations.has_key?(:presence) && validations[:presence]
           validate('presence', validations[:presence], attrs, doc_attrs)
@@ -130,7 +153,7 @@ def validates(attrs, validations)
       def validate(type, options, attrs, doc_attrs)
         validator_class = Validations::validators[type.to_s]
         if validator_class
-          @api.settings[:validations] << validator_class.new(attrs, options, doc_attrs[:required])
+          @api.settings[:validations] << validator_class.new(attrs, options, doc_attrs[:required], self)
         else
           raise "unknown validator: #{type}"
         end
@@ -145,16 +168,16 @@ def reset_validations!
       end
 
       def params(&block)
-        ParamsScope.new(self, &block)
+        ParamsScope.new(self, nil, nil, &block)
       end
 
       def document_attribute(names, opts)
         if @last_description
           @last_description[:params] ||= {}
-        
+
           Array(names).each do |name|
-            @last_description[:params][name.to_s] ||= {}
-            @last_description[:params][name.to_s].merge!(opts)
+            @last_description[:params][name[:name].to_s] ||= {}
+            @last_description[:params][name[:name].to_s].merge!(opts).merge!({:full_name => name[:full_name]})
           end
         end
       end

spec/grape/api_spec.rb

@@ -1029,7 +1029,7 @@ class CommunicationError < RuntimeError; end
       subject.routes.map { |route|
         { :description => route.route_description, :params => route.route_params }
       }.should eq [
-        { :description => "method", :params => { "ns_param" => { :required => true, :desc => "namespace parameter" }, "method_param" => { :required => false, :desc => "method parameter" } } }
+        { :description => "method", :params => { "ns_param" => { :required => true, :desc => "namespace parameter", :full_name=>"ns_param" }, "method_param" => { :required => false, :desc => "method parameter", :full_name=>"method_param" } } }
       ]
     end
     it "should merge the parameters of nested namespaces" do
@@ -1055,7 +1055,22 @@ class CommunicationError < RuntimeError; end
       subject.routes.map { |route|
         { :description => route.route_description, :params => route.route_params }
       }.should eq [
-        { :description => "method", :params => { "ns_param" => { :required => true, :desc => "ns param 2" }, "ns1_param" => { :required => true, :desc => "ns1 param" }, "ns2_param" => { :required => true, :desc => "ns2 param" }, "method_param" => { :required => false, :desc => "method param" } } }
+        { :description => "method", :params => { "ns_param" => { :required => true, :desc => "ns param 2", :full_name=>"ns_param" }, "ns1_param" => { :required => true, :desc => "ns1 param", :full_name=>"ns1_param" }, "ns2_param" => { :required => true, :desc => "ns2 param", :full_name=>"ns2_param" }, "method_param" => { :required => false, :desc => "method param", :full_name=>"method_param" } } }
+      ]
+    end
+    it "should provide a full_name for parameters in nested groups" do
+      subject.desc "nesting"
+      subject.params do
+        requires :root_param, :desc => "root param"
+        group :nested do
+          requires :nested_param, :desc => "nested param"
+        end
+      end
+      subject.get "method" do ; end
+      subject.routes.map { |route|
+        { :description => route.route_description, :params => route.route_params }
+      }.should eq [
+        { :description => "nesting", :params => { "root_param" => { :required => true, :desc => "root param", :full_name=>"root_param" }, "nested_param" => { :required => true, :desc => "nested param", :full_name=>"nested[nested_param]" } } }
       ]
     end
     it "should not symbolize params" do

spec/grape/validations/coerce_spec.rb

@@ -111,6 +111,19 @@ class User
         last_response.status.should == 201
         last_response.body.should == File.basename(__FILE__).to_s
       end
+
+      it 'Nests integers' do
+        subject.params do
+          group :integers do
+            requires :int, :coerce => Integer
+          end
+        end
+        subject.get '/int' do params[:integers][:int].class; end
+
+        get '/int', { :integers => { :int => "45" } }
+        last_response.status.should == 200
+        last_response.body.should == 'Fixnum'
+      end
     end
   end
 end

spec/grape/validations/presence_spec.rb

@@ -26,6 +26,29 @@ class API < Grape::API
         get do
           "Hello"
         end
+
+        params do
+          group :user do
+            requires :first_name, :last_name
+          end
+        end
+        get '/nested' do
+          "Nested"
+        end
+
+        params do
+          group :admin do
+            requires :admin_name
+            group :super do
+              group :user do
+                requires :first_name, :last_name
+              end
+            end
+          end
+        end
+        get '/nested_triple' do
+          "Nested triple"
+        end
       end
     end
   end
@@ -67,5 +90,49 @@ def app
     last_response.status.should == 200
     last_response.body.should == "Hello"
   end
-
+
+  it 'validates nested parameters' do
+    get('/nested')
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: first_name"
+
+    get('/nested', :user => {:first_name => "Billy"})
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: last_name"
+
+    get('/nested', :user => {:first_name => "Billy", :last_name => "Bob"})
+    last_response.status.should == 200
+    last_response.body.should == "Nested"
+  end
+
+  it 'validates triple nested parameters' do
+    get('/nested_triple')
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: admin_name"
+
+    get('/nested_triple', :user => {:first_name => "Billy"})
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: admin_name"
+
+    get('/nested_triple', :admin => {:super => {:first_name => "Billy"}})
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: admin_name"
+
+    get('/nested_triple', :super => {:user => {:first_name => "Billy", :last_name => "Bob"}})
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: admin_name"
+
+    get('/nested_triple', :admin => {:super => {:user => {:first_name => "Billy"}}})
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: admin_name"
+
+    get('/nested_triple', :admin => { :admin_name => 'admin', :super => {:user => {:first_name => "Billy"}}})
+    last_response.status.should == 400
+    last_response.body.should == "missing parameter: last_name"
+
+    get('/nested_triple', :admin => { :admin_name => 'admin', :super => {:user => {:first_name => "Billy", :last_name => "Bob"}}})
+    last_response.status.should == 200
+    last_response.body.should == "Nested triple"
+  end
+
 end