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@justalever
Created January 3, 2020 03:08
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Validate an array data type in Ruby on Rails using a custom validator - PostGresQL allows arrays as a DB type.
# Define the validator
# app/validators/array_validator.rb
class ArrayValidator < ActiveModel::EachValidator
def validate_each(record, attribute, values)
Array(values).each do |value|
options.each do |key, args|
validator_options = { attributes: attribute }
validator_options.merge!(args) if args.is_a?(Hash)
next if value.nil? && validator_options[:allow_nil]
next if value.blank? && validator_options[:allow_blank]
validator_class_name = "#{key.to_s.camelize}Validator"
validator_class = begin
validator_class_name.constantize
rescue NameError
"ActiveModel::Validations::#{validator_class_name}".constantize
end
validator = validator_class.new(validator_options)
validator.validate_each(record, attribute, value)
end
end
end
end
# include it in a model
class User
validates :tags, array: { presence: true, inclusion: { in: %w{ ruby rails } }
end
@aelhirach
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how can I use rspec to test this code

@ammarshah
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Thanks for providing this validator.

It works perfectly fine except for a little fix in using this validator in the model.

validates :tags, presence: true, array: { inclusion: { in: %w(ruby rails) } }

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