class ActionDispatch::Routing::Mapper

def devise_omniauth_callback(mapping, controllers) #:nodoc:
  if mapping.fullpath =~ /:[a-zA-Z_]/
    raise <<-ERROR
 does not support scoping OmniAuth callbacks under a dynamic segment
u have set #{mapping.fullpath.inspect}. You can work around by passing
 :omniauth_callbacks` to the `devise_for` call and extract omniauth
s to another `devise_for` call outside the scope. Here is an example:
vise_for :users, only: :omniauth_callbacks, controllers: {omniauth_callbacks: 'users/omniauth_callbacks'}
ope '/(:locale)', locale: /ru|en/ do
devise_for :users, skip: :omniauth_callbacks
d
  end
  current_scope = @scope.dup
  if @scope.respond_to? :new
    @scope = @scope.new path: nil
  else
    @scope[:path] = nil
  end
  path_prefix = Devise.omniauth_path_prefix || "/#{mapping.fullpath}/auth".squeeze("/")
  set_omniauth_path_prefix!(path_prefix)
  mapping.to.omniauth_providers.each do |provider|
    match "#{path_prefix}/#{provider}",
      to: "#{controllers[:omniauth_callbacks]}#passthru",
      as: "#{provider}_omniauth_authorize",
      via: [:get, :post]
    match "#{path_prefix}/#{provider}/callback",
      to: "#{controllers[:omniauth_callbacks]}##{provider}",
      as: "#{provider}_omniauth_callback",
      via: [:get, :post]
  end
ensure
  @scope = current_scope
end