[RUBY] Use with_options to group the same validations together!

Introduction

I will summarize the validation used in the current application creation.

Summarize common validation

with_options

Taking frequently used validation as an example

model

validates :user, presence: true
validates :item, presence: true
validates :price, presence: true
validates :email, presence: true

It's just the same thing, it's getting longer and more readable ... In such a case, you can set validation collectively with with_options.

model

with_options presence: true do
  validates :user
  validates :item
  validates :price
  validates :email
end

Using with_options more advanced

Add more individual validations

model

with_options presence: true do
  validates :user, length: { minimum: 6 }
  validates :item
  validates :price, format: { with: /\A[0-9]+\z/ }
  validates :email
end

Validation can be added individually in do ~ end. By the way, the length option can limit the number of characters. The format option specifies a regular expression.

Further summarize

model

with_options presence: true do
  validates :user
  validates :item
  with_options uniqueness: true do
    validates :price
    validates :email
  end
end

You can nest with_options inside with_options. In the above example, presence: true is set to: user,: item,: price,: email, In addition, ʻuniqueness: true` is set to: price,: email. By the way, the uniqueness option prevents you from saving the same value. (Uniqueness)

Finally

Writing together with with_options is similar to the feeling of wrapping up in common terms per factorization learning that appeared in junior high school mathematics.