redirect_to != return

I'm looking for some clarification regarding the behaviour of redirect_to.

I have this code:

if some_condition
   redirect_to(path_one)
end

redirect_to(path_two)

If some_condition == true I get this error:

> Render and/or redirect were called multiple times in this action. Please note that you may only call render OR redirect, and at most once per action.

It seems that the method continues to execute after the redirect_to call. Do I need to write code like this:

if some_condition
   redirect_to(path_one)
   return
end

redirect_to(path_two)

Yes, you need to return from method when doing redirect. It actually only adds appropriate headers for the response object.

You can write more rubyish way:

if some_condition
    return redirect_to(path_one)
end

redirect_to(path_two)

or other way:

return redirect_to(some_condition ? path_one : path_two)

or another way:

redirect_path = path_one

if some_condition
    redirect_path = path_two
end

redirect_to redirect_path

From http://api.rubyonrails.org/classes/ActionController/Base.html:

> If you need to redirect on the > condition of something, then be sure > to add “and return” to halt execution.

def do_something
  redirect_to(:action => "elsewhere") and return if monkeys.nil?
  render :action => "overthere" # won't be called if monkeys is nil
end

You can also do

redirect_to path_one and return

which reads nice.

It's worth noting there is no need to return unless you have any code after redirect_to, as in this example:

def show
  if can?(:show, :poll)
    redirect_to registrar_poll_url and return
  elsif can?(:show, Invoice)
    redirect_to registrar_invoices_url and return
  end
end

To consolidate the "rubyish way" example in Eimantas' answer to two lines of code:

return redirect_to(path_one) if some_condition

redirect_to(path_two)

If you'd like to define the redirect within a method or helper function and early return in your controller:

ActionController::Metal#performed? - Tests if render or redirect has already happened:

def some_condition_checker
  redirect_to(path_one) if some_condition
end

Call it like this:

some_condition_checker; return if performed?

redirect_to(path_two)