validates_type

Rails type validation

Purpose

Most Rails applications will have types coerced by their ORM connection adapters (like the pg gem or mysql2). However, this only useful for applications with very well defined schemas. If your application has a legacy storage layer that you can no longer modify or a lot of store_accessor columns, this solution is a nice middle ground to ensure your data is robust.

This also prevents your data from being coerced into values that you did not intend by ActiveRecord adapters.

Usage

With ActiveRecord

class Foo < ActiveRecord::Base

  # validate that attribute :bar is a String
  validates_type :bar, :string

  # validate that attribute :baz is an Integer with a custom error message
  validates_type :baz, :integer, message: 'Baz must be an Integer'

  # validate that attribute :qux is an Array, allow blank
  validates_type :qux, :array, allow_blank: true

  # validate that attribute :whatever is a Boolean
  validates_type :whatever, :boolean

  # validate that attribute :thing is a Float or nil
  validates_type :thing, :float, allow_nil: true

  # validate that attribute :when is a Time
  validates_type :when, :time

  # validate that attribute :birthday is a Date or blank
  validates_type :birthday, :date, allow_blank: true

  # validate that attribute :fox is of type Custom
  validates_type :fox, Custom
end

With ActiveModel

class Bar
  include ActiveModel::Validations

  attr_accessor :foo, :qux

  validates_type :foo, :string

  # Custom error message support
  validates_type :qux, :boolean, message: 'Attribute qux must be a boolean!'
end

With shortcut syntax

class Banana < ActiveRecord::Base

  # The banana's peel attribute must be a string
  validates :peel, type: { type: :string }

  # Custom error message for ripeness of banana
  validates :ripe, type: { type: :boolean, message: 'Only ripe bananas allowed' }
end

With multiple modifiers

class Foo < ActiveRecord::Base
  # validate that attribute :baz is an Integer with a custom error message
  #   only if :conditional_method evaluates to true
  validates_type :baz, :integer, message: 'Baz must be an Integer', if: :conditional_method

  def conditional_method
    # some kind of logic that is important to pass
  end

  # validate that attribute :baz is a Float and is included in a specific array
  validates_type :foo, :float, in: [1.0, 2.5, 3.0]
end

Supported types

• :array
• :big_decimal
• :boolean
• :date
• :float
• :hash
• :integer
• :string
• :symbol
• :time

Any class name, possibly something custom defined in your app, is also game.

Contributing

Please feel free to submit pull requests to address issues that you may find with this software. One commit per pull request is preferred please and thank you.