From ebd6ef3b36c2428723fae5d630f9ad6800f037c0 Mon Sep 17 00:00:00 2001 From: Jeff Dean Date: Sun, 9 Aug 2009 03:51:23 -0400 Subject: Added section to guide for validates with, which is scheduled for rails 3. See related ticket at: https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/2630-adding-a-validates_with-method --- .../activerecord_validations_callbacks.textile | 41 ++++++++++++++++++++++ 1 file changed, 41 insertions(+) (limited to 'railties') diff --git a/railties/guides/source/activerecord_validations_callbacks.textile b/railties/guides/source/activerecord_validations_callbacks.textile index 03d521ea1f..9d0ee29ff2 100644 --- a/railties/guides/source/activerecord_validations_callbacks.textile +++ b/railties/guides/source/activerecord_validations_callbacks.textile @@ -403,6 +403,47 @@ WARNING. Note that some databases are configured to perform case-insensitive sea The default error message for +validates_uniqueness_of+ is "_has already been taken_". +h4. +validates_with+ + +This helper passes the record to a separate class for validation. + + +class Person < ActiveRecord::Base + validates_with GoodnessValidator +end + +class GoodnessValidator < ActiveRecord::Validator + def validate + if record.first_name == "Evil" + record.errors[:base] << "This person is evil" + end + end +end + + +The +validates_with+ helper takes a class, or a list of classes to use for validation. There is no default error message for +validates_with+. You must manually add errors to the record's errors collection in the validator class. + +The validator class has two attributes by default: + +* +record+ - the record to be validated +* +options+ - the extra options that were passed to +validates_with+ + +Like all other validations, +validates_with+ takes the +:if+, +:unless+ and +:on+ options. If you pass any other options, it will send those options to the validator class as +options+: + + +class Person < ActiveRecord::Base + validates_with GoodnessValidator, :fields => [:first_name, :last_name] +end + +class GoodnessValidator < ActiveRecord::Validator + def validate + if options[:fields].any?{|field| record.send(field) == "Evil" } + record.errors[:base] << "This person is evil" + end + end +end + + h4. +validates_each+ This helper validates attributes against a block. It doesn't have a predefined validation function. You should create one using a block, and every attribute passed to +validates_each+ will be tested against it. In the following example, we don't want names and surnames to begin with lower case. -- cgit v1.2.3