anandvc / email_check

ActiveModel email validator. Checks MX records. Ships with lists of free & disposable email providers that you may want to block

EmailCheck

Description

This was originally built for Anonybuzz and is now used at StarTalent. This gem provides a robust mechanism to validate email addresses and restrict account creation to corporate email accounts.

This gem also ships with a data-set of free and disposable email domains which are used for validation checks.

You can also block certain usernames from creating accounts. Examples: admin, root

Validation mechanisms

• Uses the mail gem.
• Checks the domain's MX record
• Validate against a blacklist of domains
• Validates against a list of free email providers
• Validates against a list of disposable email providers
• A whitelist can be used to override these checks

Installation

Add this line to your application's Gemfile:

gem "check_email"

Usage

Use with ActiveModel

To validate just the format of the email address

class User < ActiveRecord::Base
  validates_email :email
end

To validate that the domain has a MX record:

validates_email :email, check_mx: true

To validate that the email is not from a disposable or free email provider:

validates_email :email, not_disposable:true, not_free:true

To validate that the domain is not blacklisted:

validates_email :email, not_blacklisted:true

To validate that the username is not blocked

validates_email :email, block_special_usernames:true

Everything together:

validates_email :email,
    check_mx: true, 
    not_disposable:true, 
    not_free:true, 
    not_blacklisted:true,
    block_special_usernames:true,
    message: "Please register with your corporate email"

To turn everything on by default, you can use the validates_email_strictness helper.

# Example above
validates_email_strictness :email

# Everything but allow free emails. This is what most people would want to use
validates_email_strictness :email, not_free:false

Modifying the inbuilt lists

The lists are exposed as assignable arrays so you can customize them or load whatever data you please.

Add a config/intializers/email_check.rb

# Set disposable email domains
EmailCheck.disposable_email_domains = ['freemail.org']
# Append to the whitelist
EmailCheck.whitelisted_domains << 'gmail.com'
EmailCheck.free_email_domains << 'thenewgmail.com'
# Setting a domain in the blacklist will also blacklist all subdomains
EmailCheck.blacklisted_domains << 'lvh.me'
# Block the 'anonymous' username for all domains
EmailCheck.blocked_usernames << 'anonymous'

Requirements

This gem is tested with Rails 4.0+. Ruby versions tested:

• Ruby 2.0
• Ruby 2.1
• Ruby 2.2
• Ruby 2.3

Rails versions tested: Rails 4.0 Rails 5.0

Credits

• This code is heavily based upon: lisinge/valid_email2
• Data is from: lavab/disposable and willwhite/freemail

Contributing

1. Fork it ( https://github.com/dapatil/email_check/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request