Devise and Mongoid in Rails 4

To use MongoDB as a database in rails application we need to use mongoid.

App source Code

mongoid #

Mongoid is an Object-Document-Mapper (ODM) for MongoDB written in Ruby
In a Rails application mongoid provide functionality like ActiveRecord, but not exactly same, because MongoDB is a document-orinted database, and that mappers is called Object Document Mappers (ODM) which maps between an Object Model and a Document Database

To use mongoDB, most of the configuration comes down by making sure that we are am not loading ActiveRecord. One way to avoid loading ActiveRecord at time of creating rails project using following switch

—skip-active-record

The Rails command that generate application skeleton now has an option -O , which commands rails to skip active record.

So, the final app skeleton will look like so:

rails new appName -T -O

open your Gemfile and add:

source 'https://rubygems.org'
source 'http://gems.github.com'

gem 'mongoid', github: "mongoid/mongoid"
gem 'bson_ext'
gem 'devise'

Now run:


bundle


create your application using(for this case to save time)

rails generate scaffold Movie name:string storyline:string

mongoid configuration #

we can configure Mongoid through a mongoid.yml file to specify options and database sessions.

we can also generate a config file by executing the following generator:

rails g mongoid:config

Devise #

Devise is a Rack based authentication solution for Rails based on Warden.

configure devise #

now run the generator:

rails g devise:install

Then create a model for authentication, generally it is named User (or Admin)

lets use the generator to do the same

rails generate devise User

It will invoke mongoid and generate cupple of files including a new entry in routes.rb.

     invoke  mongoid
      create    app/models/user.rb
      insert    app/models/user.rb
      insert    app/models/user.rb
       route  devise_for :users

Note: rails destroy devise User command may use to rollback.

 invoke  mongoid
      remove    app/models/user.rb
       route  devise_for :users

If we take a look into our newly generated User model:

class User
include Mongoid::Document
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable

  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

## Database authenticatable
  field :email, type: String, default: ""
......
......
......
end

devise composed of 10 modules (from devise wiki):

Database Authenticatable: this module responsible for encrypting password and validating authenticity of a user while signing in.

Registerable: handles signing up users through a registration process, also allowing them to edit and destroy their account.

Recoverable: resets the user password and sends reset instructions.

Rememberable: manages generating and clearing a token for remembering the user from a saved cookie.

Trackable: tracks sign in count, timestamps and IP address.

Timeoutable: expires sessions that have no activity in a specified period of time.

Validatable: provides validations of email and password.

Lockable: locks an account after a specified number of failed sign-in attempts.

Omniauthable: adds Omniauth support.

Confirmable: sends emails with confirmation instructions and verifies whether an account is already confirmed during sign in.

All set of configuration is done now we going to use it:

we can add some links to access user ‘sign in’ or ‘sign up’ path. To access those link throughout the application I going to add it in views/layout/application.rb

<div>
<% if user_signed_in? %>
    Welcome <%=  current_user.email %>
    <%= link_to "Sign out", destroy_user_session_path, :method => :delete %>
<% else %>
    <%= link_to "Sign in", new_user_session_path%> or <%= link_to "Sign up", new_user_registration_path %>
<% end %>
</div>

To protect controller add a filter, we are going to protect all other action other than movie listing page:

# In our controllers
before_filter :authenticate_user!, :except => [:index]

That’s it :)