PostcodeValidator

A simple postcode validator based on the Unicode CLDR project, with an optional integration with ActiveModel.

PostcodeValidator is distributed as a gem and available on rubygems.org so you can add it to your Gemfile or install it manually with:

gem install postcode_validator

You can use PostcodeValidator either as a stand-alone validator or integrated with ActiveModel.

require 'postcode_validator'

validator = PostcodeValidator.new

validator.valid?('98025', country: 'FR') # True
validator.valid?('AB21 9BG', country: :GB) # True
validator.valid?('AB21 9BG', country: :DE) # False
validator.valid?('', country: 'PA') # True - Panama does not use postcodes.

The :country option is required. It can be anything that respond to to_s. If the supplied :country is not a valid ISO-3166 country code, a PostcodeValidator::Error will be raised.

class Address < ActiveRecord::Base

  # With a dedicated helper
  validates_as_postcode :zipcode, country: :US

  # Or through the generic `validates` class method, mixed with other validators
  validates :post_code,
    presence: true,
    postcode: { allow_nil: true, country: -> { |record| record.country_code } }
end

The ActiveModel validator supports the same common arguments others standard validators do (:if, :unless, :on, :allow_nil, :allow_blank and :strict). The :country argument is required. It can be either a static value (anything that respond to to_s) or a lambda. The lambda will be called with the will be validated record as its first argument.

If the supplied :country is not a valid ISO-3166 country code, the postcode validation will be skipped (It's your responsability to validate the value of :country).

Bug reports and pull requests are welcome on GitHub at https://github.com/notus-sh/postcode_validator.