[Ruby on Rails]Redirect to RESTful URL - ruby-on-rails

Question

I am working on a movie rails project and I have to redirect the url to be RESTful, but I have no idea how to make it done. The following information may be useful:
I fail to: GET /movies when selecting a movie rating should redirect to a RESTful route
rake routes:
Prefix Verb URI Pattern Controller#Action
root GET / movies#index
movies GET /movies(.:format) movies#index
POST /movies(.:format) movies#create
new_movie GET /movies/new(.:format) movies#new
edit_movie GET /movies/:id/edit(.:format) movies#edit
movie GET /movies/:id(.:format) movies#show
PATCH /movies/:id(.:format) movies#update
PUT /movies/:id(.:format) movies#update
DELETE /movies/:id(.:format) movies#destroy
The UI of the webpage
Some descriptions of what I have to do: (generally saying if the user intentionally deletes some attributes from the url, I have redirect it to the correct url):
To be RESTful, we want to preserve the property that a URI that results in a sorted/filtered view always contains the corresponding sorting/filtering parameters.
The code I have implemented to do the task:
if !(params.has_key?(:sort_by)) #check the url has this parameter
if session[:sort_by] #has cookie
redirect_to movies_path(:sort_by => session[:sort_by]) #redirect using cookie, not sure need to add :ratings
else
session[:sort_by] = "id" # default sorting
end
end
if !(params.has_key?(:ratings))
if session[:ratings]
redirect_to movies_path(:ratings => session[:ratings]) # error: AbstractController::DoubleRenderError
else
session[:rating] = {"G"=>"1", "PG"=>"1", "PG-13"=>"1", "R"=>"1"}
end
end
:sort_by is the attribute to control how is the movies sorted, e.g. session[:sort_by] = "date" means sorted on the release date.
:ratings is something like: "ratings"=>{"G"=>"1", "PG-13"=>"1", "R"=>"1"}
An example of URL: /movies?ratings%5BG%5D=1&ratings%5BPG%5D=1&ratings%5BPG-13%5D=1&ratings%5BR%5D=1&sort_by=title
if I type something like .../movies, the url should be generated from cookie(if any). But I am having some problems:
for example we check that sort_by is missing, and there is session for sort_by, do we still need to supply session[:ratings] to movies_path()? And what to do if it is the first time I come to this website (no session[:ratings]/session[:sort_by]) but I still need the RESTful URL(all checked boxes are 'clicked' by default)
Some more instructions:
So you should redirect when parameters are missing in URL, instead of in URL + session.
It means that when ‘sort_by’ is not in the URL, but in the session, you should complete this URL with session data, and redirect to the complete URL (so fill in if ‘ratings’ is also missing).
Now what if a parameter is missing in both URL and session? You should rely on some initialization rules. For ‘ratings’, you should check all ratings; and for ‘sort_by’, you can set the keyword to ‘id’, which is how items are sorted by default (the order of movies in the array returned by Movie.all).

Answer 1

Something like this should work
def index
session[:sort_by] = if params[:sort_by].present?
params[:sort_by]
else
session[:sort_by] || 'id'
end
session[:rating] = if params[:rating].present?
params[:rating]
else
session[:rating] || { 'G' => '1', 'PG' => '1', 'PG-13' => '1', 'R' => '1' }
end
if !(params[:sort_by].present? && params[:rating].present?)
redirect_to movies_path(sort_by: session[:sort_by], rating: session[:rating])
return
end
end
First couple lines set up the session to the parameter value if one was passed in, otherwise checks for an existing session value, and then falls back to the default.
Then, we look to see if either the sort_by or the rating parameter were missing, we'll redirect to include both of them from the new values in the session.
I believe this hits all your criteria. The main problem you were having is that as soon as you call redirect_to, it's going to try and redirect, it doesn't like having code (especially other redirect or render calls) after it. So you need to check any conditions you need and then lump it all into one redirect call and then return from the method so it doesn't try to also render.