Ruby on Rails Gems Install & Implementation

FIGARO:

Purpose of Use.

Figaro was written to make it easy to securely configure Rails applications.

How to impliment .

Step:1>>In Gemfile:
gem 'figaro', '~> 1.1'

Step:2>>$ bundle install or gem install figaro

Step:3>>$ figaro install / rails generate figaro:install

 It creates a commented config/application.yml file and adds it to your .gitignore.
 Add your own configuration to this file and you're done!

Step:4>>
config/application.yml
 
  DEV_DB_USERNAME: 'xx'
  DEV_DB_PASSWORD: 'xxxxx'
  DEV_DB_NAME: 'xxxxx'

And here is my database.yml :

development:
  adapter: postgresql
  encoding: unicode
  database: <%= ENV['DEV_DB_NAME'] %>
  pool: 5
  username: <%= ENV['DEV_DB_USERNAME'] %>
  password: <%= ENV['DEV_DB_PASSWORD'] %>
  template: template0

AUDITED

Purpose of Use.

Audited (previously acts_as_audited) is an ORM extension that logs all changes to your models.
Audited also allows you to record who made those changes, save comments and associate models related to the changes.

How to impliment .

Step:1>> in Gemfile:
gem "audited", "~> 4.0"
Step:2>> $ bundle install or gem install audited

Step:3>>$ rails generate audited:install

After Step 3 it must create db/20151102092358_install_audited.rb file
if not
Step:1.1>In Gemfile:(add one more gem)
gem 'audited-activerecord', '~> 4.2'
Step:2 & 3


20151102092358_install_audited.rb
-------------------------------------------------------------
class InstallAudited < ActiveRecord::Migration
  def self.up
    create_table :audits, :force => true do |t|
      t.column :auditable_id, :integer
      t.column :auditable_type, :string
      t.column :associated_id, :integer
      t.column :associated_type, :string
      t.column :user_id, :integer
      t.column :user_type, :string
      t.column :username, :string
      t.column :action, :string
      t.column :audited_changes, :text
      t.column :version, :integer, :default => 0
      t.column :comment, :string
      t.column :remote_address, :string
      t.column :request_uuid, :string
      t.column :created_at, :datetime
    end

    add_index :audits, [:auditable_id, :auditable_type], :name => 'auditable_index'
    add_index :audits, [:associated_id, :associated_type], :name => 'associated_index'
    add_index :audits, [:user_id, :user_type], :name => 'user_index'
    add_index :audits, :request_uuid
    add_index :audits, :created_at
  end

  def self.down
    drop_table :audits
  end
end
------------------------------------------------------------------------------------


Step:4>> $ rake db:migrate
It will create table name 'audits' which will have column

Step:5>> if u want all changes to audited .

class User < ActiveRecord::Base
  audited
end
It will store all changes of users into audits table.

EXIFR

Purpose of Use.

EXIF Reader is a module to read metadata from JPEG and TIFF images.

How to impliment .

Step:1>>In Gemfile:
gem 'exifr', '~> 1.2'

Step:2>>$ bundle install or gem install exifr

Step:3>>
now you can get the value & save it in the table you want .

EXIFR::JPEG.new('IMG_6841.JPG').width               # => 2272
EXIFR::JPEG.new('IMG_6841.JPG').height              # => 1704
EXIFR::JPEG.new('IMG_6841.JPG').exif?               # => true
EXIFR::JPEG.new('IMG_6841.JPG').software            # => Picasa 

EXIFR::TIFF.new('DSC_0218.TIF')[1].width            # => 160
EXIFR::TIFF.new('DSC_0218.TIF').model               # => "NIKON D1X"
EXIFR::TIFF.new('DSC_0218.TIF').date_time           # => Tue May 23 19:15:32 +0200 2006