refactoring rails redirects with multiple ifs - ruby-on-rails

Question

In the app I am working on, the user can get to a new form from several different places. I need to redirect them back to where they came from. I solved it by passing a parameter in the link on the view, for example
= link_to "create a new post »", new_user_post_path(#current_user, :return_to => 'dashboard')
then in the new action in the controller like so
if params[:return_to] == 'dashboard'
session[:return_to]= 'dashboard'
end
now I am looking at the controller. what I need to do I can achieve by being really verbose, but I'm looking for a more elegant solution. Here is what I have now
if #user_post.save
flash[:notice] = "New Post Created"
if session[:return_to] == 'dashboard'
session.delete(:return_to)
redirect_to dashboard_path and return
else
redirect_to user_hub_path(#user)
end
else
flash[:error] = "Could not save post"
redirect_to new_user_post_path(#user)
end
This does what I need but I was hoping to tidy it up a little. I started looking at 1 line enumerators to see if I could do something like this...
if #user_post.save
flash[:notice] = "New post Created"
session[:return_to] == 'dashboard' ? redirect_to "#{session.delete(:return_to)}_path" : redirect_to user_hub_path(#user)
else
flash[:error] = "Could not save post"
redirect_to new_user_post_path(#user)
end
but it really doesn't like this part....redirect_to "#{session.delete(:return_to)}_path"
any advice? Guess I'm trying to get it to redirect and delete the session in one line and this is beyond my knowledge...

Answer 1

This looks like a good case for using Rails' built-in :back parameter, which, according to the Rails docs here, sends the user "Back to the page that issued the request. Useful for forms that are triggered from multiple places. Short-hand for redirect_to(request.env["HTTP_REFERER"])"
You can avoid passing a return_to param, and change your controller code to:
if #user_post.save
redirect_to :back, notice: "New Post Created" and return
else
redirect_to new_user_post_path(#user), flash: { error: "Could not save post" }
end

Answer 2

What about using send?
send takes a message name and optional arguments and forwards that to send's receiver (http://ruby-doc.org/core-2.2.0/Object.html#method-i-send)
path = send("#{session.delete(:return_to)}_path")
redirect_to path
In this case it sends the message to the current controller instance (same as just calling the ..._path method but gives the flexibility of the dynamic call)

Answer 3

Please instead of using a redirect_to variable of your controller, use the Referer Header.
HTTP referer (originally a misspelling of referrer) is an HTTP header field that identifies the address of the webpage (i.e. the URI or IRI) that linked to the resource being requested
In Rails is quite simple inside a controller
redirect_to request.referer
That is more elegant and efficient, because the session cookie storage can be expensive (cache storage) and could affect your HTTP cache proxies performance.