Module: Sack::Database::Model::Relationships::ClassMethods

Defined in:
lib/sack/database/model/relationships.rb,
lib/sack/database/model/relationships/has_many.rb,
lib/sack/database/model/relationships/belongs_to.rb

Overview

Class Methods

Instance Method Summary collapse

Instance Method Details

#belongs_to(options) ⇒ Object

Belongs To: Defines the ‘slave’ end of any relationship (the one that holds the other entity’s ID).

Parameters:

  • options (Object) —

    Either a Symbol indicating both the name of the relationship and the target model, or an option Hash defining the relationship - see README



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# File 'lib/sack/database/model/relationships/belongs_to.rb', line 22

def belongs_to options

	# Check Options
	if options.is_a? Hash

		# Internalise Options (so we can mess it up)
		options = options.clone

		# Pull Relationship Name & Target Model
		name, target_model_name = options.first
		options.delete name
	else

		# Acquire everything from just a Symbol
		name = options
		target_model_name = name
	end

	# Construct Proxy Method Module
	proxy = Module.new do

		# Proxy Method for Relationship:
		# Allows fetching entities for a given belongs-to relationship.
		define_method name do |db, data|

			# Find Target Model
			target_model = @model_root.const_get target_model_name.to_s.camelcase

			# Fetch Relationship Entity
			target_model.find db, data[name]
		end
	end

	# Extend Model with Proxy
	@model.extend proxy
end

#has_many(options) ⇒ Object

Has Many: Defines the ‘one’ side a one-to-many relationship.

Parameters:

  • options (Hash) —

    Options defining the relationship - see README



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# File 'lib/sack/database/model/relationships/has_many.rb', line 22

def has_many options

	# Internalise Options (so we can mess it up)
	options = options.dclone

	# Pull Relationship Name & Target Model
	name, target_model_name = options.first
	options.delete name

	# Determine Foreign Key (which field in the remote model holds our ID)
	foreign_key = options[:fk] || table_name

	# Register Relationship
	relationships[name] = { target: target_model_name, fk: foreign_key, options: options.dclone }

	# Construct Proxy Method Module
	proxy = Module.new do

		# Proxy Method for Relationship:
		# Allows fetching entities for a given has-many relationship.
		define_method name do |db, data|

			# Find Target Model
			target_model = @model_root.const_get target_model_name.to_s.camelcase

			# Fetch Relationship Entities
			target_model.fetch_by db, foreign_key, data[:id]
		end
	end

	# Extend Model with Proxy
	@model.extend proxy
end

#relationships ⇒ Object

Relationships: Gets the relationships for the Model.



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# File 'lib/sack/database/model/relationships.rb', line 34

def relationships
	@relationships ||= {}
end