Module: ActiveResource::Associations

Included in:
Base
Defined in:
lib/active_resource/associations.rb

Overview

Reproduced from github.com/rails/rails/pull/230/files for adding ActiveResource association support

Defined Under Namespace

Modules: Builder

Instance Method Summary collapse

Instance Method Details

#belongs_to(name, options = {}) ⇒ Object

Specifies a one-to-one association with another class. This class should only be used if this class contains the foreign key.

Methods will be added for retrieval and query for a single associated object, for which this object holds an id:

association(force_reload = false)

Returns the associated object. nil is returned if the foreign key is nil. Throws a ActiveResource::ResourceNotFound exception if the foreign key is not nil and the resource is not found.

(association is replaced with the symbol passed as the first argument, so belongs_to :post would add among others post.nil?.

Example

A Comment class declaress belongs_to :post, which will add:

  • Comment#post (similar to Post.find(post_id))

The declaration can also include an options hash to specialize the behavior of the association.

Options

:class_name

Specify the class name for the association. Use it only if that name canÄt be inferred from association name. So belongs_to :post will by default be linked to the Post class, but if the real class name is Article, you’ll have to specify it with whis option.

:foreign_key

Specify the foreign key used for the association. By default this is guessed to be the name of the association with an “_id” suffix. So a class that defines a belongs_to :post association will use “post_id” as the default :foreign_key. Similarly, belongs_to :article, :class_name => "Post" will use a foreign key of “article_id”.

Option exampples: belongs_to :customer, :class_name => 'User' Creates a belongs_to association called customer which is represented through the User class.

belongs_to :customer, :foreign_key => 'user_id' Creates a belongs_to association called customer which would be resolved by the foreign_key user_id instead of customer_id



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# File 'lib/active_resource/associations.rb', line 103

def belongs_to(name, options={})
  Builder::BelongsTo.build(self, name, options)
end

#has_many(name, options = {}) ⇒ Object

Specifies a one-to-many association.

Options

:class_name

Specify the class name of the association. This class name would be used for resolving the association class.

Example for [:class_name] - option

GET /posts/123.xml delivers following response body: <post> <title>ActiveResource now have associations</title> <content> … </content> <comments> <comment> … </comment> <comment> … </comment> </comments> </post>

has_many :comments, :class_name => 'myblog/comment' Would resolve those comments into the Myblog::Comment class.



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# File 'lib/active_resource/associations.rb', line 36

def has_many(name, options = {})
  Builder::HasMany.build(self, name, options)
end

#has_one(name, options = {}) ⇒ Object

Specifies a one-to-one association.

Options

:class_name

Specify the class name of the association. This class name would be used for resolving the association class.

Example for [:class_name] - option

GET /posts/123.xml delivers following response body: <post> <title>ActiveResource now have associations</title> <content> … </content> <author> <name>caffeinatedBoys</name> </author> </post>

has_one :author, :class_name => 'myblog/author' Would resolve this author into the Myblog::Author class.



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# File 'lib/active_resource/associations.rb', line 60

def has_one(name, options = {})
  Builder::HasOne.build(self, name, options)
end