IpFormat

This is a gem that leverages the Resolv library to validate IP addresses. This can handle both, IPV4 and IPV6.

Add this line to your application's Gemfile:

gem 'ip_format'

And then execute:

$ bundle

Or install it yourself as:

$ gem install ip_format

In order to validate an attribute, use the validates keyword:

class Device < ActiveRecord::Base

  # ...

  validates :ip, ip_format: true

  # ...

end

Now the ip attribute will be validated:

Device.new(ip: 'invalidip').valid?        # => false
Device.new(ip: '192.68.0.1').valid? # => true

Also, the model in question doesn't need to inherit from ActiveRecord::Base, you only need to include ActiveModel::Validations in your class:

require 'ip_format'

class Awesome
  include ActiveModel::Validations
  attr_accessor :ip
  validates :ip, ip_format: true
end

awesome = Awesome.new

awesome.ip = "fde4:8dba:82e1::"
awesome.valid? # => true

awesome.ip = "invalidip"
awesome.valid? # => false

There are two other validators, ipv4_format and ipv6_format. They can be called in place of ip_format if you want the IP address to be validated specifically against IPV4 or IPV6.

The below example validates against the IPV6 format regex defined by the Resolv gem.

require 'ip_format'

class Awesome
  include ActiveModel::Validations
  attr_accessor :ip
  validates :ip, ipv6_format: true
end

awesome = Awesome.new

awesome.ip = "fde4:8dba:82e1::"
awesome.valid? # => true

awesome.ip = "192.68.0.1"
awesome.valid? # => false

The below example validates against the IPV4 format regex defined by the Resolv gem.

require 'ip_format'

class Awesome
  include ActiveModel::Validations
  attr_accessor :ip
  validates :ip, ipv4_format: true
end

awesome = Awesome.new

awesome.ip = "fde4:8dba:82e1::"
awesome.valid? # => false

awesome.ip = "192.68.0.1"
awesome.valid? # => true

IP Format uses Resolv, which comes with the Ruby standard lib. This ensures that a new dependency isn't introduced, keeping away the bloat that is sometimes involved with adding gems that have a long line of dependencies.

The ipaddress gem is a great option if you need a more robust solution with subnetting and prefix information. If that functionality isn't a requirement, then the IP Format gem is what you're looking for; it's as simple and lightweight as can be (assuming you're already using ActiveModel).

1. Fork it ( https://github.com/a10networks/ip_format/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