# encoding: utf-8
module Mongoid
module Validations
# Validates whether or not a field is unique against the documents in the
# database.
#
# @example Define the uniqueness validator.
#
# class Person
# include Mongoid::Document
# field :title
#
# validates_uniqueness_of :title
# end
class UniquenessValidator < ActiveModel::EachValidator
include Queryable
# Validate the document for uniqueness violations.
#
# @example Validate the document.
# validate_each(person, :title, "Sir")
#
# @param [ Document ] document The document to validate.
# @param [ Symbol ] attribute The field to validate on.
# @param [ Object ] value The value of the field.
#
# @return [ Errors ] The errors.
#
# @since 1.0.0
def validate_each(document, attribute, value)
with_query(document) do
attrib, val = to_validate(document, attribute, value)
return unless validation_required?(document, attrib)
if document.embedded?
validate_embedded(document, attrib, val)
else
validate_root(document, attrib, val)
end
end
end
private
# Add the error to the document.
#
# @api private
#
# @example Add the error.
# validator.add_error(doc, :name, "test")
#
# @param [ Document ] document The document to validate.
# @param [ Symbol ] attribute The name of the attribute.
# @param [ Object ] value The value of the object.
#
# @since 2.4.10
def add_error(document, attribute, value)
document.errors.add(
attribute, :taken, options.except(:case_sensitive, :scope).merge(value: value)
)
end
# Should the uniqueness validation be case sensitive?
#
# @api private
#
# @example Is the validation case sensitive?
# validator.case_sensitive?
#
# @return [ true, false ] If the validation is case sensitive.
#
# @since 2.3.0
def case_sensitive?
!(options[:case_sensitive] == false)
end
# Create the validation criteria.
#
# @api private
#
# @example Create the criteria.
# validator.create_criteria(User, user, :name, "syd")
#
# @param [ Class, Proxy ] base The base to execute the criteria from.
# @param [ Document ] document The document to validate.
# @param [ Symbol ] attribute The name of the attribute.
# @param [ Object ] value The value of the object.
#
# @return [ Criteria ] The criteria.
#
# @since 2.4.10
def create_criteria(base, document, attribute, value)
field = document.fields[attribute.to_s]
criteria = scope(base.unscoped, document, attribute)
if field.try(:localized?)
criteria.selector.update(criterion(document, attribute, value))
else
criteria = criteria.where(criterion(document, attribute, value))
end
criteria
end
# Get the default criteria for checking uniqueness.
#
# @api private
#
# @example Get the criteria.
# validator.criterion(person, :title, "Sir")
#
# @param [ Document ] document The document to validate.
# @param [ Symbol ] attribute The name of the attribute.
# @param [ Object ] value The value of the object.
#
# @return [ Criteria ] The uniqueness criteria.
#
# @since 2.3.0
def criterion(document, attribute, value)
selector = { attribute => filter(value) }
if document.persisted? && !document.embedded?
selector.merge!(_id: { "$ne" => document.id })
end
selector
end
# Filter the value based on whether the check is case sensitive or not.
#
# @api private
#
# @example Filter the value.
# validator.filter("testing")
#
# @param [ Object ] value The value to filter.
#
# @return [ Object, Regexp ] The value, filtered or not.
#
# @since 2.3.0
def filter(value)
!case_sensitive? && value ? /\A#{Regexp.escape(value.to_s)}$/i : value
end
# Scope the criteria to the scope options provided.
#
# @api private
#
# @example Scope the criteria.
# validator.scope(criteria, document)
#
# @param [ Criteria ] criteria The criteria to scope.
# @param [ Document ] document The document being validated.
#
# @return [ Criteria ] The scoped criteria.
#
# @since 2.3.0
def scope(criteria, document, attribute)
Array.wrap(options[:scope]).each do |item|
name = document.database_field_name(item)
criteria = criteria.where(item => document.attributes[name])
end
criteria = criteria.where(deleted_at: nil) if document.paranoid?
criteria
end
# Should validation be skipped?
#
# @api private
#
# @example Should the validation be skipped?
# validator.skip_validation?(doc)
#
# @param [ Document ] document The embedded document.
#
# @return [ true, false ] If the validation should be skipped.
#
# @since 2.3.0
def skip_validation?(document)
!document._parent || document.embedded_one?
end
# Scope reference has changed?
#
# @api private
#
# @example Has scope reference changed?
# validator.scope_value_changed?(doc)
#
# @param [ Document ] document The embedded document.
#
# @return [ true, false ] If the scope reference has changed.
#
# @since
def scope_value_changed?(document)
Array.wrap(options[:scope]).any? do |item|
document.send("attribute_changed?", item.to_s)
end
end
# Get the name of the field and the value to validate. This is for the
# case when we validate a relation via the relation name and not the key,
# we need to send the key name and value to the db, not the relation
# object.
#
# @api private
#
# @example Get the name and key to validate.
# validator.to_validate(doc, :parent, Parent.new)
#
# @param [ Document ] document The doc getting validated.
# @param [ Symbol ] attribute The attribute getting validated.
# @param [ Object ] value The value of the attribute.
#
# @return [ Array<Object, Object> ] The field and value.
#
# @since 2.4.4
def to_validate(document, attribute, value)
metadata = document.relations[attribute.to_s]
if metadata && metadata.stores_foreign_key?
[ metadata.foreign_key, value.id ]
else
[ attribute, value ]
end
end
# Validate an embedded document.
#
# @api private
#
# @example Validate the embedded document.
# validator.validate_embedded(doc, :name, "test")
#
# @param [ Document ] document The document.
# @param [ Symbol ] attribute The attribute name.
# @param [ Object ] value The value.
#
# @since 2.4.10
def validate_embedded(document, attribute, value)
return if skip_validation?(document)
relation = document._parent.send(document.metadata_name)
criteria = create_criteria(relation, document, attribute, value)
add_error(document, attribute, value) if criteria.count > 1
end
# Validate a root document.
#
# @api private
#
# @example Validate the root document.
# validator.validate_root(doc, :name, "test")
#
# @param [ Document ] document The document.
# @param [ Symbol ] attribute The attribute name.
# @param [ Object ] value The value.
#
# @since 2.4.10
def validate_root(document, attribute, value)
criteria = create_criteria(document.class, document, attribute, value)
if criteria.with(consistency: :strong).exists?
add_error(document, attribute, value)
end
end
# Are we required to validate the document?
#
# @example Is validation needed?
# validator.validation_required?(doc, :field)
#
# @param [ Document ] document The document getting validated.
# @param [ Symbol ] attribute The attribute to validate.
#
# @return [ true, false ] If we need to validate.
#
# @since 2.4.4
def validation_required?(document, attribute)
document.new_record? ||
document.send("attribute_changed?", attribute.to_s) ||
scope_value_changed?(document)
end
end
end
end