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Diffstat (limited to 'activemodel/README.rdoc')
| -rw-r--r-- | activemodel/README.rdoc | 128 |
1 files changed, 67 insertions, 61 deletions
diff --git a/activemodel/README.rdoc b/activemodel/README.rdoc index 3262bf61ac..f6beff14e1 100644 --- a/activemodel/README.rdoc +++ b/activemodel/README.rdoc @@ -1,8 +1,8 @@ = Active Model -- model interfaces for Rails Active Model provides a known set of interfaces for usage in model classes. -They allow for Action Pack helpers to interact with non-ActiveRecord models, -for example. Active Model also helps building custom ORMs for use outside of +They allow for Action Pack helpers to interact with non-Active Record models, +for example. Active Model also helps with building custom ORMs for use outside of the Rails framework. Prior to Rails 3.0, if a plugin or gem developer wanted to have an object @@ -11,7 +11,7 @@ code from Rails, or monkey patch entire helpers to make them handle objects that did not exactly conform to the Active Record interface. This would result in code duplication and fragile applications that broke on upgrades. Active Model solves this by defining an explicit API. You can read more about the -API in ActiveModel::Lint::Tests. +API in <tt>ActiveModel::Lint::Tests</tt>. Active Model provides a default module that implements the basic API required to integrate with Action Pack out of the box: <tt>ActiveModel::Model</tt>. @@ -24,8 +24,8 @@ to integrate with Action Pack out of the box: <tt>ActiveModel::Model</tt>. end person = Person.new(name: 'bob', age: '18') - person.name # => 'bob' - person.age # => '18' + person.name # => 'bob' + person.age # => '18' person.valid? # => true It includes model name introspections, conversions, translations and @@ -49,7 +49,8 @@ behavior out of the box: send("#{attr}=", nil) end end - + + person = Person.new person.clear_name person.clear_age @@ -78,16 +79,31 @@ behavior out of the box: class Person include ActiveModel::Dirty - attr_accessor :name + define_attribute_methods :name + + def name + @name + end + + def name=(val) + name_will_change! unless val == @name + @name = val + end + + def save + # do persistence work + changes_applied + end end person = Person.new - person.name # => nil - person.changed? # => false + person.name # => nil + person.changed? # => false person.name = 'bob' - person.changed? # => true - person.changed # => ['name'] - person.changes # => { 'name' => [nil, 'bob'] } + person.changed? # => true + person.changed # => ['name'] + person.changes # => { 'name' => [nil, 'bob'] } + person.save person.name = 'robert' person.save person.previous_changes # => {'name' => ['bob, 'robert']} @@ -109,16 +125,19 @@ behavior out of the box: attr_reader :errors def validate! - errors.add(:name, "can not be nil") if name.nil? + errors.add(:name, "cannot be nil") if name.nil? end def self.human_attribute_name(attr, options = {}) "Name" end end - + + person = Person.new + person.name = nil + person.validate! person.errors.full_messages - # => ["Name can not be nil"] + # => ["Name cannot be nil"] {Learn more}[link:classes/ActiveModel/Errors.html] @@ -128,29 +147,11 @@ behavior out of the box: extend ActiveModel::Naming end - NamedPerson.model_name # => "NamedPerson" + NamedPerson.model_name.name # => "NamedPerson" NamedPerson.model_name.human # => "Named person" {Learn more}[link:classes/ActiveModel/Naming.html] -* Observer support - - ActiveModel::Observers allows your object to implement the Observer - pattern in a Rails App and take advantage of all the standard observer - functions. - - class PersonObserver < ActiveModel::Observer - def after_create(person) - person.logger.info("New person added!") - end - - def after_destroy(person) - person.logger.warn("Person with an id of #{person.id} was destroyed!") - end - end - - {Learn more}[link:classes/ActiveModel/Observer.html] - * Making objects serializable ActiveModel::Serialization provides a standard interface for your object @@ -198,41 +199,41 @@ behavior out of the box: * Validation support - class Person - include ActiveModel::Validations + class Person + include ActiveModel::Validations - attr_accessor :first_name, :last_name + attr_accessor :first_name, :last_name - validates_each :first_name, :last_name do |record, attr, value| - record.errors.add attr, 'starts with z.' if value.to_s[0] == ?z - end - end + validates_each :first_name, :last_name do |record, attr, value| + record.errors.add attr, 'starts with z.' if value.to_s[0] == ?z + end + end - person = Person.new - person.first_name = 'zoolander' - person.valid? # => false + person = Person.new + person.first_name = 'zoolander' + person.valid? # => false {Learn more}[link:classes/ActiveModel/Validations.html] * Custom validators + + class HasNameValidator < ActiveModel::Validator + def validate(record) + record.errors[:name] = "must exist" if record.name.blank? + end + end - class ValidatorPerson - include ActiveModel::Validations - validates_with HasNameValidator - attr_accessor :name - end - - class HasNameValidator < ActiveModel::Validator - def validate(record) - record.errors[:name] = "must exist" if record.name.blank? - end - end + class ValidatorPerson + include ActiveModel::Validations + validates_with HasNameValidator + attr_accessor :name + end - p = ValidatorPerson.new - p.valid? # => false - p.errors.full_messages # => ["Name must exist"] - p.name = "Bob" - p.valid? # => true + p = ValidatorPerson.new + p.valid? # => false + p.errors.full_messages # => ["Name must exist"] + p.name = "Bob" + p.valid? # => true {Learn more}[link:classes/ActiveModel/Validator.html] @@ -261,6 +262,11 @@ API documentation is at * http://api.rubyonrails.org -Bug reports and feature requests can be filed with the rest for the Ruby on Rails project here: +Bug reports can be filed for the Ruby on Rails project here: * https://github.com/rails/rails/issues + +Feature requests should be discussed on the rails-core mailing list here: + +* https://groups.google.com/forum/?fromgroups#!forum/rubyonrails-core + |