Rails, Subdomain based cookies

I have a rails application which is Subdomain based. It also contains REST API which can be publicly accessed to our clients. I have an another client application through which I am accessing the REST API of the main app.

When I am accessing both the apps on the same browser and logged in the main app, I am not able to access the REST API of different Subdomain in client app as cookie get stored according to the domain accessed.

Is there any way to differentiate the cookies based on Subdomain.

Thanks in advance.

You should set cookie's domain as .yourdomain.com so that your cookies are set for main domain and for all subdomains.

Rails 3 on config/initializers/session_store.rb:

Rails.application.config.session_store :cookie_store, :key => '_my_key', :domain => ".yourdomain.com"

Rails 2.3+ on config/environment.rb:

config.action_controller.session = { :key => '_my_key', :domain => '.yourdomain.com' }