# How to use Controller instance methods inside (Web Service) API Services

**URL:** <https://www.ruby-forum.com/t/how-to-use-controller-instance-methods-inside-web-service-api-services/161970>\
**Category:** Rails\
**Created:** [March 4, 2009, 11:15am UTC](https://www.ruby-forum.com/t/how-to-use-controller-instance-methods-inside-web-service-api-services/161970 "2009-03-04T11:15:23Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Piyush\_with\_Rails](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/ec9cab/32.png) [@Piyush\_with\_Rails](https://www.ruby-forum.com/u/Piyush_with_Rails)\
**Post date:** [March 4, 2009, 11:15am UTC](https://www.ruby-forum.com/t/how-to-use-controller-instance-methods-inside-web-service-api-services/161970/1 "2009-03-04T11:15:23Z")

</div>

Hi All,

I am using AWS to implement web service APIs in rails and i am using  
Layered dispatching mode for implementation.

Here i am not getting how can i use controller’s instance methods  
(both user defined and built in) inside my API service.

As an example below take below things in consideration.

this is API signature.

class ProductApi \< ActionWebService::API::Base

```
 api_method :find_all_products,
 :returns => [[:int]]

api_method :find_product_by_id,
:expects => [:int],
 :returns => [Product]

```

end

this is layered\_backend controller.

class LayeredBackendController \< ApplicationController

```
  dispatching_web_service_mode :layered
  web_service_scaffold :invoke
  web_service(:order) { OrderService.new }

  def test_method
     # some code
  end

```

end

this is order\_service.rb file.

class OrderService\< ActionWebService::Base  
web\_service\_api ProductApi

```
 def find_all_products
     Product.find(:all).map{ |product| product.id }
 end

 def find_product_by_id(id)
     Product.find(id)
 end

```

end

Now if i want to use my controller instance method named test\_method  
inside OrderServie then how can i use it ?

and also how to use controller built in instance methods (like  
session, log\_error etc )inside OrderService ?

Thanks in Advance.

Piyush.