Before Rails 4.x to easily navigate back once the action is complete we used to use redirect_to :back method that looks something like this:

class OrdersController < ApplicationController
  def approve
    order = Order.find params[:id]
    order.approve!

    redirect_to :back
  end
end

This action will approve the order and redirect the user to the previous location where he performed this action from. However, if this action was performed and the HTTP_REFERER is missing, which can lead to ActionController::RedirectBackError exception to be raised.

Rescue the exception

One way to solve this method is to rescue the Exception and redirect to the default location.

class OrdersController < ApplicationController
  rescue_from ActionController::RedirectBackError, with: :redirect_to_default


  def approve
    order = Order.find params[:id]
    order.approve!

    redirect_to :back
  end

  private

  def redirect_to_default
    redirect_to orders_path
  end
end

Using redirect_back

After Rails 5.x, we can use redirect_back it accept fallback_location as an argument where we can provide the fallback location if the HTTP_REFERER is empty.

class OrdersController < ApplicationController
  def approve
    order = Order.find params[:id]
    order.approve!

    redirect_back fallback_location: orders_path
  end
end