render works fine but redirect_to does not

rubyonrails-talk
1

Hello, I have an application where I am getting an odd error. If I do redirect_to url I get a DoubleRenderError. If I change that redirect_to url to a render :text => url. The action works fine.

Why would I receive this error just by changing the way rails is responding?

Regards, Devin

2

The error is telling you that you are using redirect/render twice in the same action. Please post the controller code that is giving you the error so the group can better help you find the source of your error.

B.

3

Heres the error:

AbstractController::DoubleRenderError in FoursquareController#authenticate app/controllers/foursquare_controller.rb:10:in `location' app/controllers/foursquare_controller.rb:33:in `authenticate'

And the code:

def location     session[:geolat] = params[:geolat]     session[:geolong] = params[:geolong]     render :nothing => true end def authenticate     redirect_to "Log in? client_id=#{FOURSQUARE_OAUTH_CONFIG[:client_id]} &response_type=code&redirect_uri=#{FOURSQUARE_OAUTH_CONFIG[:redirect_uri]}" end

Why does it even call location when thats not even mentioned the action being called? I only get this error if i change authenticate to have redirect_to

4

Heres the error:

AbstractController::DoubleRenderError in FoursquareController#authenticate app/controllers/foursquare_controller.rb:10:in `location' app/controllers/foursquare_controller.rb:33:in `authenticate'

And the code:

def location    session[:geolat] = params[:geolat]    session[:geolong] = params[:geolong]    render :nothing => true end def authenticate    redirect_to "Log in? client_id=#{FOURSQUARE_OAUTH_CONFIG[:client_id]} &response_type=code&redirect_uri=#{FOURSQUARE_OAUTH_CONFIG[:redirect_uri]}" end

Why does it even call location when thats not even mentioned the action being called? I only get this error if i change authenticate to have redirect_to

From the error message it appears you are calling authenticate from what is being rendered on a location call.

5

Heres the error:

AbstractController::DoubleRenderError in FoursquareController#authenticate app/controllers/foursquare_controller.rb:10:in `location' app/controllers/foursquare_controller.rb:33:in `authenticate'

And the code:

def location    session[:geolat] = params[:geolat]    session[:geolong] = params[:geolong]    render :nothing => true end def authenticate    redirect_to "Log in? client_id=#{FOURSQUARE_OAUTH_CONFIG[:client_id]} &response_type=code&redirect_uri=#{FOURSQUARE_OAUTH_CONFIG[:redirect_uri]}" end

Why does it even call location when thats not even mentioned the action being called? I only get this error if i change authenticate to have redirect_to

Hit send before I meant to. It looks like, from the error message, that from your render action in location you are calling authenticate which then tries to redirect before the render from location is complete. This is a no no. It works when you switch it to render_to because that is a acting like a nested render which is ok. You might want to rethink how you want to do that authentication if you really need that redirect.

B.