Module: Remotely::Associations::ClassMethods

Defined in:
lib/remotely/associations.rb

Overview

A set class methods for defining associations that are retreived from a remote API. They’re available to all classes which inherit from ActiveRecord::Base orRemotely::Model.

class Show < ActiveRecord::Base
  has_many_remote   :members
  has_one_remote    :set
  belongs_to_remote :station
end

Warning

Just like with ActiveRecord, associations will overwrite any instance method with the same name as the association. So don’t do that.

Cardinality and Defining Associations

Remotely can be used to specify one-to-one and one-to-many associations. Many-to-many is not supported.

Unlike ActiveRecord, remote associations are only defined on the client side. has_many relations have no accompanying belongs_to.

One-to-many

Use has_many_remote to define a one-to-many relationship where the model you are defining it in is the parent.

URI Assumptions

Remotely assumes all has_many_remote associations can be found at:

/model_name(plural)/id/association_name(plural)

Example

class User < ActiveRecord::Base
  has_many_remote :friends
end

user = User.new(:id => 1)
user.friends # => /users/1/friends

One-to-one

Use has_one_remote to define a one-to-one relationship.

URI Assumptions

Remotely assumes all has_one_remote associations can be found at:

/model_name(plural)/id/association_name(singular)

Example

class Car < ActiveRecord::Base
  has_one_remote :engine
end

car = Car.new(:id => 1)
car.engine # => /cars/1/engine

Many-to-one

Use belongs_to_remote to define a many-to-one relationship. That is, if the model you’re defining this on has a foreign key to the remote model.

URI Assumptions

Remotely assumes all belongs_to_remote associations can be found at:

/association_name(plural)/{association_name}_id

Example

class Car < ActiveRecord::Base
  belongs_to_remote :brand
end

car = Car.new(:brand_id => 2)
car.brand # => /brands/2

Options

:path

The full URI that should be used to fetch this resource. (supported by all methods)

:foreign_key

The attribute that should be used, instead of id when generating URIs. (supported by belongs_to_remote only)

Path Variables

The path option will replace any symbol(ish) looking string with the value of that attribute, of the model.

class User < ActiveRecord::Base
  belongs_to_remote :family, :path => "/families/:family_key"
end

user = User.new(:family_key => "noble")
user.family # => /families/noble

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#remote_associations ⇒ Object

Remote associations defined and their options.



111
112
113
 
# File 'lib/remotely/associations.rb', line 111

def remote_associations
  @remote_associations
end

Instance Method Details

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

Specifies a many-to-one relationship.

Parameters:

  • name (Symbol) —

    Name of the relationship

  • options (Hash) (defaults to: {}) —

    Association configuration options.

Options Hash (options):

  • :path (String) —

    Path to the remote resource

  • :foreign_key (Symbol, String) —

    Attribute to be used in place of id when constructing URIs.



141
142
143
 
# File 'lib/remotely/associations.rb', line 141

def belongs_to_remote(name, options={})
  define_association_method(:belongs_to, name, options)
end

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

Specifies a one-to-many relationship.

Parameters:

  • name (Symbol) —

    Name of the relationship

  • options (Hash) (defaults to: {}) —

    Association configuration options.

Options Hash (options):

  • :path (String) —

    Path to the remote resource



119
120
121
 
# File 'lib/remotely/associations.rb', line 119

def has_many_remote(name, options={})
  define_association_method(:has_many, name, options)
end

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

Specifies a one-to-one relationship.

Parameters:

  • name (Symbol) —

    Name of the relationship

  • options (Hash) (defaults to: {}) —

    Association configuration options.

Options Hash (options):

  • :path (String) —

    Path to the remote resource



129
130
131
 
# File 'lib/remotely/associations.rb', line 129

def has_one_remote(name, options={})
  define_association_method(:has_one, name, options)
end