Omniauth: callback fails, returns failure with "invalid credentials"

The facebook authentication in my Rails app, implemented with a Omniauth

gem, has stopped working recently.

The problem is that the controller action to be used by the callback does not start and the process immediately jumps to an "invalid credentials" error.

Magazine:

Started GET "/auth/facebook" for ::ffff:127.0.0.1 at 2017-03-29 11:12:29 +0200
Started GET "/auth/facebook/callback?code=<<code>>&state=<<state>" for ::ffff:127.0.0.1 at 2017-03-29 11:12:30 +0200
Started GET "/auth/failure?message=invalid_credentials&origin=<<origin>>&strategy=facebook" for ::ffff:127.0.0.1 at 2017-03-29 11:12:31 +0200
Started GET "/login" for ::ffff:127.0.0.1 at 2017-03-29 11:12:31 +0200
Processing by UserSessionsController#new as HTML

      

        
        
        
      

    

routes:

  match "/auth/failure" => redirect("/login"), :via => [:get, :post]
  match '/auth/:provider/callback' => 'user_sessions#create_omniauth', :via => [:get, :post]
  match '/auth/:provider/disconnect' => 'user_sessions#destroy_omniauth', :as => :destroy_auth, :via => :delete

      

        
        
        
      

    

Any ideas what could be wrong?

Edit: I had the same google authorization issue.