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diff --git a/guides/source/active_model_basics.md b/guides/source/active_model_basics.md index 4b2bfaee2f..ee0472621b 100644 --- a/guides/source/active_model_basics.md +++ b/guides/source/active_model_basics.md @@ -8,12 +8,12 @@ classes. Active Model allows for Action Pack helpers to interact with plain Ruby objects. Active Model also helps build custom ORMs for use outside of the Rails framework. -After reading this guide, you will be able to add to plain Ruby objects: +After reading this guide, you will know: -* The ability to behave like an Active Record model. -* Callbacks and validations like Active Record. -* Serializers. -* Integration with the Rails internationalization (i18n) framework. +* How an Active Record model behaves. +* How Callbacks and validations work. +* How serializers work. +* How Active Model integrates with the Rails internationalization (i18n) framework. -------------------------------------------------------------------------------- @@ -87,7 +87,7 @@ end ### Conversion If a class defines `persisted?` and `id` methods, then you can include the -`ActiveModel::Conversion` module in that class and call the Rails conversion +`ActiveModel::Conversion` module in that class, and call the Rails conversion methods on objects of that class. ```ruby @@ -156,16 +156,17 @@ person.changed? # => false person.first_name = "First Name" person.first_name # => "First Name" -# returns if any attribute has changed. +# returns true if any of the attributes have unsaved changes. person.changed? # => true # returns a list of attributes that have changed before saving. person.changed # => ["first_name"] -# returns a hash of the attributes that have changed with their original values. +# returns a Hash of the attributes that have changed with their original values. person.changed_attributes # => {"first_name"=>nil} -# returns a hash of changes, with the attribute names as the keys, and the values will be an array of the old and new value for that field. +# returns a Hash of changes, with the attribute names as the keys, and the +# values as an array of the old and new values for that field. person.changes # => {"first_name"=>[nil, "First Name"]} ``` @@ -179,7 +180,7 @@ person.first_name # => "First Name" person.first_name_changed? # => true ``` -Track what was the previous value of the attribute. +Track the previous value of the attribute. ```ruby # attr_name_was accessor @@ -187,7 +188,7 @@ person.first_name_was # => nil ``` Track both previous and current value of the changed attribute. Returns an array -if changed, else returns nil. +if changed, otherwise returns nil. ```ruby # attr_name_change @@ -197,7 +198,7 @@ person.last_name_change # => nil ### Validations -`ActiveModel::Validations` module adds the ability to validate class objects +The `ActiveModel::Validations` module adds the ability to validate objects like in Active Record. ```ruby @@ -225,7 +226,7 @@ person.valid? # => raises ActiveModel::StrictValidationFa ### Naming -`ActiveModel::Naming` adds a number of class methods which make the naming and routing +`ActiveModel::Naming` adds a number of class methods which make naming and routing easier to manage. The module defines the `model_name` class method which will define a number of accessors using some `ActiveSupport::Inflector` methods. @@ -248,7 +249,7 @@ Person.model_name.singular_route_key # => "person" ### Model -`ActiveModel::Model` adds the ability to a class to work with Action Pack and +`ActiveModel::Model` adds the ability for a class to work with Action Pack and Action View right out of the box. ```ruby @@ -292,8 +293,8 @@ objects. ### Serialization -`ActiveModel::Serialization` provides a basic serialization for your object. -You need to declare an attributes hash which contains the attributes you want to +`ActiveModel::Serialization` provides basic serialization for your object. +You need to declare an attributes Hash which contains the attributes you want to serialize. Attributes must be strings, not symbols. ```ruby @@ -308,7 +309,7 @@ class Person end ``` -Now you can access a serialized hash of your object using the `serializable_hash`. +Now you can access a serialized Hash of your object using the `serializable_hash` method. ```ruby person = Person.new @@ -319,14 +320,14 @@ person.serializable_hash # => {"name"=>"Bob"} #### ActiveModel::Serializers -Rails provides two serializers `ActiveModel::Serializers::JSON` and -`ActiveModel::Serializers::Xml`. Both of these modules automatically include -the `ActiveModel::Serialization`. +Active Model also provides the `ActiveModel::Serializers::JSON` module +for JSON serializing / deserializing. This module automatically includes the +previously discussed `ActiveModel::Serialization` module. ##### ActiveModel::Serializers::JSON -To use the `ActiveModel::Serializers::JSON` you only need to change from -`ActiveModel::Serialization` to `ActiveModel::Serializers::JSON`. +To use `ActiveModel::Serializers::JSON` you only need to change the +module you are including from `ActiveModel::Serialization` to `ActiveModel::Serializers::JSON`. ```ruby class Person @@ -340,7 +341,8 @@ class Person end ``` -With the `as_json` you have a hash representing the model. +The `as_json` method, similar to `serializable_hash`, provides a Hash representing +the model. ```ruby person = Person.new @@ -349,8 +351,8 @@ person.name = "Bob" person.as_json # => {"name"=>"Bob"} ``` -From a JSON string you define the attributes of the model. -You need to have the `attributes=` method defined on your class: +You can also define the attributes for a model from a JSON string. +However, you need to define the `attributes=` method on your class: ```ruby class Person @@ -370,7 +372,7 @@ class Person end ``` -Now it is possible to create an instance of person and set the attributes using `from_json`. +Now it is possible to create an instance of `Person` and set attributes using `from_json`. ```ruby json = { name: 'Bob' }.to_json @@ -379,62 +381,6 @@ person.from_json(json) # => #<Person:0x00000100c773f0 @name="Bob"> person.name # => "Bob" ``` -##### ActiveModel::Serializers::Xml - -To use the `ActiveModel::Serializers::Xml` you only need to change from -`ActiveModel::Serialization` to `ActiveModel::Serializers::Xml`. - -```ruby -class Person - include ActiveModel::Serializers::Xml - - attr_accessor :name - - def attributes - {'name' => nil} - end -end -``` - -With the `to_xml` you have an XML representing the model. - -```ruby -person = Person.new -person.to_xml # => "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<person>\n <name nil=\"true\"/>\n</person>\n" -person.name = "Bob" -person.to_xml # => "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<person>\n <name>Bob</name>\n</person>\n" -``` - -From an XML string you define the attributes of the model. -You need to have the `attributes=` method defined on your class: - -```ruby -class Person - include ActiveModel::Serializers::Xml - - attr_accessor :name - - def attributes=(hash) - hash.each do |key, value| - send("#{key}=", value) - end - end - - def attributes - {'name' => nil} - end -end -``` - -Now it is possible to create an instance of person and set the attributes using `from_xml`. - -```ruby -xml = { name: 'Bob' }.to_xml -person = Person.new -person.from_xml(xml) # => #<Person:0x00000100c773f0 @name="Bob"> -person.name # => "Bob" -``` - ### Translation `ActiveModel::Translation` provides integration between your object and the Rails @@ -446,8 +392,8 @@ class Person end ``` -With the `human_attribute_name` you can transform attribute names into a more -human format. The human format is defined in your locale file. +With the `human_attribute_name` method, you can transform attribute names into a +more human-readable format. The human-readable format is defined in your locale file(s). * config/locales/app.pt-BR.yml @@ -465,19 +411,18 @@ Person.human_attribute_name('name') # => "Nome" ### Lint Tests -`ActiveModel::Lint::Tests` allow you to test whether an object is compliant with +`ActiveModel::Lint::Tests` allows you to test whether an object is compliant with the Active Model API. -* app/models/person.rb +* `app/models/person.rb` ```ruby class Person include ActiveModel::Model - end ``` -* test/models/person_test.rb +* `test/models/person_test.rb` ```ruby require 'test_helper' @@ -485,14 +430,14 @@ the Active Model API. class PersonTest < ActiveSupport::TestCase include ActiveModel::Lint::Tests - def setup + setup do @model = Person.new end end ``` ```bash -$ rake test +$ rails test Run options: --seed 14596 @@ -512,20 +457,20 @@ features out of the box. ### SecurePassword `ActiveModel::SecurePassword` provides a way to securely store any -password in an encrypted form. On including this module, a +password in an encrypted form. When you include this module, a `has_secure_password` class method is provided which defines -an accessor named `password` with certain validations on it. +a `password` accessor with certain validations on it. #### Requirements -`ActiveModel::SecurePassword` depends on the [`bcrypt`](https://github.com/codahale/bcrypt-ruby 'BCrypt'), -so include this gem in your Gemfile to use `ActiveModel::SecurePassword` correctly. +`ActiveModel::SecurePassword` depends on [`bcrypt`](https://github.com/codahale/bcrypt-ruby 'BCrypt'), +so include this gem in your `Gemfile` to use `ActiveModel::SecurePassword` correctly. In order to make this work, the model must have an accessor named `password_digest`. The `has_secure_password` will add the following validations on the `password` accessor: 1. Password should be present. -2. Password should be equal to its confirmation. -3. This maximum length of a password is 72 (required by `bcrypt` on which ActiveModel::SecurePassword depends) +2. Password should be equal to its confirmation (provided `password_confirmation` is passed along). +3. The maximum length of a password is 72 (required by `bcrypt` on which ActiveModel::SecurePassword depends) #### Examples @@ -546,10 +491,14 @@ person.password = 'aditya' person.password_confirmation = 'nomatch' person.valid? # => false -# When the length of password, exceeds 72. +# When the length of password exceeds 72. person.password = person.password_confirmation = 'a' * 100 person.valid? # => false +# When only password is supplied with no password_confirmation. +person.password = 'aditya' +person.valid? # => true + # When all validations are passed. person.password = person.password_confirmation = 'aditya' person.valid? # => true |