Devise Masquerade

It's a utility library for enabling functionallity like login as button for admin.

If you have multi users application and sometimes you want to test functionally using login of existing user without requesting the password, define login as button with url helper and use it.

Installation

Add this line to your application's Gemfile:

gem 'devise_masquerade'

And then execute:

$ bundle

Usage

In the view you can use url helper for defining link:

    = link_to "Login As", masquerade_path(user)

masquerade_path would create specific /masquerade path with query params masquerade(key) and masqueraded_resource_class to know which model to choose to search and sign in by masquerade key.

In the model you'll need to add the parameter :masqueradable to the existing comma separated values in the devise method:

    devise :invitable, :confirmable, :database_authenticatable, :registerable, :masqueradable

Add into your application_controller.rb if you want to have custom way on sign in by using masquerade token otherwise you can still use only masquerade_path in your view to generate temporary token and link to make Login As:

    before_action :masquerade_user!

    before_action :masquerade!

masquerade! is generic way in case if you want to support multiple models on masquerade.

Instead of user you can use your resource name admin, student or another names.

If you want to back to the owner of masquerade action user you could use helpers:

    user_masquerade? # current user was masqueraded by owner?

    = link_to "Reverse masquerade", back_masquerade_path(current_user)

Custom controller for adding cancan for authorization

    class Admin::MasqueradesController < Devise::MasqueradesController
      def show
        super
      end

      protected

      def masquerade_authorize!
        authorize!(:masquerade, User)
      end

      # or you can define:
      # def masquerade_authorized?
      #   <has access to something?> (true/false)
      # end
    end

Alternatively using Pundit

Controller:

    class Admin::MasqueradesController < Devise::MasqueradesController
      protected

      def masquerade_authorize!
        authorize(User, :masquerade?) unless params[:action] == 'back'
      end
    end

In your view:

    <% if policy(@user).masquerade? %>
      <%= link_to "Login as", masquerade_path(@user) %>
    <% end %>

Custom url redirect after masquerade:

    class Admin::MasqueradesController < Devise::MasqueradesController
      protected

      def after_masquerade_path_for(resource)
        "/custom_url"
      end
    end

Custom url redirect after finishing masquerade:

    class Admin::MasqueradesController < Devise::MasqueradesController
      protected

      def after_back_masquerade_path_for(resource)
        "/custom_url"
      end
    end

Overriding the finder

For example, if you use FriendlyId:

    class Admin::MasqueradesController < Devise::MasqueradesController
      protected

      def find_masqueradable_resource
        masqueraded_resource_class.friendly.find(params[:id])
      end
    end

Dont forget to update your Devise routes to point at your Custom Authorization Controller

in routes.rb:

    devise_for :users, controllers: { masquerades: "admin/masquerades" }

You can redefine few options:

    Devise.masquerade_param = 'masquerade'
    Devise.masquerade_expires_in = 10.seconds
    Devise.masquerade_key_size = 16 # size of the generate by SecureRandom.urlsafe_base64
    Devise.masquerade_bypass_warden_callback = false
    Devise.masquerade_routes_back = false # if true, route back to the page the user was on via redirect_back
    Devise.masquerading_resource_class = AdminUser
    # optional: Devise.masquerading_resource_class_name = 'AdminUser'

    # optional, default: masquerading_resource_class.model_name.param_key
    Devise.masquerading_resource_name = :admin_user

    Devise.masqueraded_resource_class = User
    # optional: Devise.masqueraded_resource_class_name = 'User'

    # optional, default: masqueraded_resource_class.model_name.param_key
    Devise.masqueraded_resource_name = :user

    # optional, default: masquerade_storage_method = :session
    # values: :session, :cache
    Devise.masquerade_storage_method = :session

Demo project

cd spec/dummy
rake db:setup
rails server

And check http://localhost:3000/, use for login user1@example.com and 'password'

Troubleshooting

Are you working in development mode and wondering why masquerade attempts result in a Receiving "You are already signed in" flash[:error] message? Filter chain halted as :require_no_authentication rendered or redirected showing up in your logfile? Do you find that your user_masquerade? method is always returning false? Chances are that you need to enable caching:

rails dev:cache

This is a one-time operation, so you can set it and forget it. Should you ever need to disable caching in development, you can re-run the command as required.

Test project

make test

Contributing

Fork it
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create new Pull Request