How to force Rails to abandon flash messages when transitioning to Angularjs?

Question

Currently I am developing a site that uses a pure angularjs single page js application backed by rails. The only thing that is still using rails views are the devise pages for login,password reset, etc. Once the user is logged in, I forward them to angularjs url. However, when the user logs out, they are returned to rails signin page where they see a very stale flash message.

I was thinking I can just have Angular do a $http ping to rails controller which forces rails to do flash.clear(). But this doesn't seem to work. When I logout, the last devise message is still there.

Answer 1

I would recommend clearing hash inside your application controller unless it is devise controller so you dont need to do extra http rest call for that. Here is what you can do

in your application_controller.rb add before filter that clears flash unless it is a devise controller:

before_filter :discard_flash, :unless => :devise_controller?

private

def discard_flash
  flash.discard              # discard the entire flash at the end of the current action
  flash.discard(:warning)    # discard only the "warning" entry at the end of the current action
end

now when a user is interacting with your application, flash object will be discarded if it is not a devise controller, so you will still show flash messages if user types wrong password... if user signs in successfully and hits non devise controller, then flash object will be discarded. for api reference please look at following links: http://api.rubyonrails.org/classes/ActionDispatch/Flash/FlashHash.html and http://rubydoc.info/github/plataformatec/devise/master/Devise/Controllers/Helpers