Module: Fend::Plugins::ExternalValidation

Defined in:

lib/fend/plugins/external_validation.rb

Overview

‘external_validation` plugin allows you to delegate param validations to external classes/objects.

plugin :external_validation

External validation must respond to ‘call` method that takes param value as an argument and returns error messages either as an array or hash (nested data).

class CustomEmailValidator
  def initialize
    @errors = []
  end

  def call(email_value)
    @errors << "must be string" unless email_value.is_a?(String)
    @errors << "must be unique" unless unique?(email_value)

    @errors
  end

  def unique?(value)
    UniquenessCheck.call(value)
  end
end

class AddressValidation < Fend
  plugin :validation_options

  validate do |i|
    i.params(:city, :street) do |city, street|
      city.validate(type: String)
      street.validate(type: String)
    end
  end
end

class UserValidation < Fend
  plugin :external_validation

  validate do |i|
    i.params(:email, :address) do |email, address|
      email.validate_with(CustomEmailValidation.new)

      address.validate_with(AddressValidation)
    end
  end
end

‘validation_options` plugin supports `external_validation`:

email.validate(with: CustomEmailValidation.new)

You are free to combine internal and external validations any way you like. Using one doesn’t mean you can’t use the other.

Defined Under Namespace

Modules: ParamMethods