Ruby on Rails | Validation | strict

概要

strict

詳細

ActiveRecordで、validation時にstrictを利用することで、
検証エラー時に例外(ActiveModel::StrictValidationFailed)を投げます。
また、自分で任意のエラーを指定することも可能です。

サンプル

テーブル定義

CREATE TABLE "articles" (
  "id" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, 
  "title" varchar(255), 
  "text" text, 
  "created_at" datetime, 
  "updated_at" datetime
);

Validation その1 例外クラス指定なし時

class Article < ActiveRecord::Base
  has_many :comments, dependent: :destroy
  validates :title, length: { is: 5 , strict: true}
end

試行 その1 例外クラス指定なし時

rails console(pry)で試行します。

[1] pry(main)> a = Article.new
=> #<Article id: nil, title: nil, text: nil, created_at: nil, updated_at: nil>
[2] pry(main)> a.title = '5'
=> "5"
[3] pry(main)> a.valid?
ActiveModel::StrictValidationFailed: Title is the wrong length (should be 5 characters)
from /home/vagrant/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activemodel-4.1.1/lib/active_model/errors.rb:296:in `add'
[4] pry(main)> a.title = '12345'
=> "12345"
[5] pry(main)> a.valid?
=> true

Validation その2 例外クラス指定あり時

class SomeUserDefineError < StandardError;end

class Article < ActiveRecord::Base
  has_many :comments, dependent: :destroy
  validates :title, length: { is: 5 }, strict: SomeUserDefineError
end

試行 その2 例外クラス指定あり時

rails console(pry)で試行します。

[1] pry(main)> a = Article.new
=> #<Article id: nil, title: nil, text: nil, created_at: nil, updated_at: nil>
[2] pry(main)> a.title = '5'
=> "5"
[3] pry(main)> a.valid?
SomeUserDefineError: Title is the wrong length (should be 5 characters)
from /home/vagrant/.rbenv/versions/2.1.2/lib/ruby/gems/2.1.0/gems/activemodel-4.1.1/lib/active_model/errors.rb:296:in `add'
[4] pry(main)> a.title = '12345'
=> "12345"
[5] pry(main)> a.valid?
=> true