ip_address_validator

A localizable EachValidator for IPv4 and IPv6 address fields, with optional restrictions on CIDR, loopback, private, and reserved ranges. Works with any class that uses ActiveModel::Validations (Rails models, plain Ruby objects that include ActiveModel::Validations, etc.).

Installation

gem "ip_address_validator", "~> 2.0"

Requires Ruby 3.1 or newer and activemodel >= 6.1.

Usage

class User
  include ActiveModel::Validations
  attr_accessor :last_login_ip

  validates :last_login_ip, ip_address: true
end

Options

Option	Default	Description
`:ipv4_only`	`false`	If `true`, IPv6 addresses are considered invalid.
`:ipv6_only`	`false`	If `true`, IPv4 addresses are considered invalid.
`:allow_cidr`	`false`	If `true`, CIDR notation (e.g. `10.0.0.0/24`) is accepted. Otherwise any value containing `/` is rejected.
`:no_loopback`	`false`	If `true`, loopback addresses (`127.0.0.0/8`, `::1`) are rejected.
`:no_private`	`false`	If `true`, RFC 1918 ranges and IPv6 unique local (`fc00::/7`) are rejected.
`:no_reserved`	`false`	If `true`, link-local, multicast, broadcast, documentation, and other reserved blocks are rejected.
`:message`	—	Custom error message.
`:allow_nil`	`false`	If `true`, `nil` values are allowed.
`:allow_blank`	`false`	If `true`, blank values are allowed.

Examples

# Only allow public, non-CIDR IPv4 addresses.
validates :webhook_source_ip, ip_address: {
  ipv4_only: true,
  no_loopback: true,
  no_private: true,
  no_reserved: true
}

# Allow a CIDR block (e.g. for an IP allowlist field).
validates :allowlist_entry, ip_address: { allow_cidr: true }

# Custom message.
validates :remote_ip, ip_address: { message: "must be a valid IP" }

Localization

The error key is invalid_ip. Define it under the usual ActiveModel errors hierarchy:

en:
  activemodel:
    errors:
      messages:
        invalid_ip: "is not a valid IP address"

Development

bin/setup
bundle exec rspec

License

Released under the MIT License. See LICENSE.