Ruby on Rails -- independant controller method for static pages

So basically I want to use a simple controller method with no params:

def create_message
   @a = Message.create(:body => "Hello")
   @a.save
   redirect_to messages_path
end

but i'm routing from the home page, pages controller:

def home
end

I'm having a problem figuring out what to write in the routes file, I've tried almost everything including but not limited to:

resources :pages do
  collection do
   get :create_message
  end
end

Views:

<%= link_to "Create Message", create_message_pages_path, class:"btn btn-primary"%>

Error:

The action 'create_message' could not be found for PagesController