Module: ActiveRemote::Association::ClassMethods

Defined in:
lib/active_remote/association.rb

Instance Method Summary collapse

Instance Method Details

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

Create a ‘belongs_to` association for a given remote resource. Specify one or more associations to define. The constantized class must be loaded into memory already. A method will be defined with the same name as the association. When invoked, the associated remote model will issue a `search` for the :guid with the associated guid attribute and return the first remote object from the result, or nil.

A ‘belongs_to` association should be used when the associating remote contains the guid to the associated model. For example, if a User model `belongs_to` Client, the User model would have a client_guid field that is used to search the Client service. The Client model would have no reference to the user.

Examples

class User
  belongs_to :client
end

An equivalent code snippet without a ‘belongs_to` declaration would be:

Examples

class User
  def client
    Client.search(:guid => self.client_guid).first
  end
end



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# File 'lib/active_remote/association.rb', line 35

def belongs_to(belongs_to_klass, options = {})
  perform_association(belongs_to_klass, options) do |klass, object|
    foreign_key = options.fetch(:foreign_key) { :"#{klass.name.demodulize.underscore}_guid" }
    search_hash = {}
    search_hash[:guid] = object.send(foreign_key)
    search_hash[options[:scope]] = object.send(options[:scope]) if options.key?(:scope)

    search_hash.values.any?(&:nil?) ? nil : klass.search(**search_hash).first
  end
end

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

Create a ‘has_many` association for a given remote resource. Specify one or more associations to define. The constantized class must be loaded into memory already. A method will be defined with the same plural name as the association. When invoked, the associated remote model will issue a `search` for the :guid with the associated guid attribute.

A ‘has_many` association should be used when the associated model has a field to identify the associating model, and there can be multiple remotes associated. For example, if a Client has many Users, the User remote would have a client_guid field that is searchable. That search would likely return multiple user records. The client would not have a field indicating which users are associated.

Examples

class Client
  has_many :users
end

An equivalent code snippet without a ‘has_many` declaration would be:

Examples

class Client
  def users
    User.search(:client_guid => self.guid)
  end
end



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# File 'lib/active_remote/association.rb', line 76

def has_many(has_many_class, options = {})
  perform_association(has_many_class, options) do |klass, object|
    foreign_key = options.fetch(:foreign_key) { :"#{object.class.name.demodulize.underscore}_guid" }
    search_hash = {}
    search_hash[foreign_key] = object.guid
    search_hash[options[:scope]] = object.send(options[:scope]) if options.key?(:scope)

    search_hash.values.any?(&:nil?) ? [] : klass.search(**search_hash)
  end

  options[:has_many] = true
  create_association_writer(has_many_class, options)
end

#has_one(has_one_klass, options = {}) ⇒ Object

Create a ‘has_one` association for a given remote resource. Specify one or more associations to define. The constantized class must be loaded into memory already. A method will be defined with the same name as the association. When invoked, the associated remote model will issue a `search` for the :guid with the associated guid attribute and return the first remote object in the result, or nil.

A ‘has_one` association should be used when the associated remote contains the guid from the associating model. For example, if a User model `has_one` Client, the Client remote would have a user_guid field that is searchable. The User model would have no reference to the client.

Examples

class User
  has_one :client

An equivalent code snippet without a ‘has_one` declaration would be:

Examples

class User
  def client
    Client.search(:user_guid => self.guid).first
  end
end



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# File 'lib/active_remote/association.rb', line 116

def has_one(has_one_klass, options = {})
  perform_association(has_one_klass, options) do |klass, object|
    foreign_key = options.fetch(:foreign_key) { :"#{object.class.name.demodulize.underscore}_guid" }
    search_hash = {}
    search_hash[foreign_key] = object.guid
    search_hash[options[:scope]] = object.send(options[:scope]) if options.key?(:scope)

    search_hash.values.any?(&:nil?) ? nil : klass.search(**search_hash).first
  end
end

#validate_scoped_attributes(associated_class, object_class, options) ⇒ Object

when requiring an attribute on your search, we verify the attribute exists on both models



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# File 'lib/active_remote/association.rb', line 129

def validate_scoped_attributes(associated_class, object_class, options)
  raise "Could not find attribute: '#{options[:scope]}' on #{object_class}" unless object_class.public_instance_methods.include?(options[:scope])
  raise "Could not find attribute: '#{options[:scope]}' on #{associated_class}" unless associated_class.public_instance_methods.include?(options[:scope])
end