Question

I would like to associate the current_user when I associate this objects on Bar create, another thing, is this way right? Or should I do this on type controller?

Model Bar

belongs_to :type
belongs_to :user

Model Type

has_many :bars

Model User

has_one :bar

Bar Controller

def new
  @bar = Bar.new(:type_id => @type.id)
end

def create
  @bar = current_user.build_bar(params[:bar].merge(:type_id => @type.id))
  if  @bar.save     
  flash.now[:success] = "wohoo!"
    render  :edit
  else
    render  :new 
  end
end

Answer 1

The following is the general Rails approach to creating a model through an association – assuming that current_user is set during login or elsewhere and @type is set appropriately in a before_filter.

In the Bar Controller:

def new
  @bar = current_user.bar.build
end

def create
  @bar = current_user.bar.build(params[:bar].merge(:type_id => @type.id))
  if  @bar.save     
    flash.now[:success] = "wohoo!"
    redirect_to @bar
  else
    render  :new 
  end
end

Building through the association in this way will automatically set the user_id field on bar to the current_user.id.

Note also that you will likely want to redirect_to rather than render on the success case. If you want to go to edit directly then user redirect_to edit_bar_path(@bar). If you want to see more info about why then check out the Layouts and Rendering Rails Guide which discusses render v redirect and the implications of each.