Class: Mongoid::Association::Referenced::HasManyThrough

Relationships & Source Files
Namespace Children
Classes: `Eager`, `Proxy`
Super Chains via Extension / Inclusion / Inheritance
Instance Chain: self, `::Mongoid::Association::Relatable`, `::Mongoid::Association::Options`, `::Mongoid::Association::Constrainable`
Inherits:	Object
Defined in:	lib/mongoid/association/referenced/has_many_through.rb, lib/mongoid/association/referenced/has_many_through/eager.rb, lib/mongoid/association/referenced/has_many_through/proxy.rb

Overview

Metadata class for has_many :through associations.

Constant Summary

ASSOCIATION_OPTIONS =

The options available for this type of association, in addition to the common ones.
Returns:
- (Array<Symbol>) —
  The extra valid options.
# File 'lib/mongoid/association/referenced/has_many_through.rb', line 17
```
%i[order source through].freeze
```
VALID_OPTIONS =

The complete list of valid options for this association, including the shared ones.
Returns:
- (Array<Symbol>) —
  The valid options.
# File 'lib/mongoid/association/referenced/has_many_through.rb', line 23
```
(ASSOCIATION_OPTIONS + SHARED_OPTIONS).freeze
```

`::Mongoid::Association::Relatable` - Included

PRIMARY_KEY_DEFAULT, SHARED_OPTIONS

Instance Attribute Summary

#embedded? ⇒ false readonly

Is this association embedded?
#stores_foreign_key? ⇒ false readonly

Through associations never store a foreign key on the owner document.

`::Mongoid::Association::Relatable` - Included

#destructive?	Whether the dependent method is destructive.
#in_to?	Is this association an embedded_in or belongs_to association?
#many?	Is this association an embeds_many or has_many association?
#many_to_many?	Is this association a many-to-many association? Such an association stores its foreign keys as an array on the document itself.
#name	The name of the association.
#one?	Is this association an embeds_one or has_one association?
#options	The options on this association.
#owner_class	The class that owns this association.
#parent_inclusions	The associations above this one in the inclusion tree.
#parent_inclusions=	The associations above this one in the inclusion tree.
#validate?	Whether the associated object(s) should be validated.

`::Mongoid::Association::Options` - Included

#autobuilding?	Whether the association is autobuilding.
#autosave	`::Mongoid::Association::Options` to save any loaded members and destroy members that are marked for destruction when the parent object is saved.
#autosave?	Alias for Options#autosave.
#cascading_callbacks?	Whether the association has callbacks cascaded down from the parent.
#counter_cached?	Whether the association is counter-cached.
#cyclic?	Is the association cyclic.
#fallback	Invokes the `:fallback` Proc and returns the null object that stands in for the association when its actual value is nil.
#fallback?	Whether the association has a `:fallback` (null object) option set.
#forced_nil_inverse?	Whether the association has forced nil inverse (So no foreign keys are saved).
#indexed?	Whether to index the primary or foreign key field.
#polymorphic?	Whether this association is polymorphic.
#touchable?	Whether the association object should be automatically touched when its inverse object is updated.

Instance Method Summary

#criteria(base) ⇒ Mongoid::Criteria

Return a ::Mongoid::Criteria scoped to the target documents reachable from base via the through association.
#relation ⇒ Class

The proxy class for this association type.
#relation_complements ⇒ Array

The list of association complements.
#setup! ⇒ self

Setup instance methods on the owner class.
#source_association ⇒ Mongoid::Association::Relatable

The source association metadata on the intermediate class.
#through_association ⇒ Mongoid::Association::Relatable

The intermediate association metadata on the owner class.
#validation_default ⇒ false

The default for validating the association object.
#default_primary_key private
#define_readonly_setter! private
#define_through_getter! private
#define_through_ids_getter! private
#key_values(criteria, key) ⇒ Array<Object> private

Pluck the given key from the criteria, dropping intermediates that have no value for it.
#setup_instance_methods! private

`::Mongoid::Association::Relatable` - Included

#==	Compare this association to another.
#bindable?	Whether trying to bind an object using this association should raise an error.
#class_name	Alias for Mongoid::Association::Relatable#relation_class_name.
#counter_cache_column_name	Get the counter cache column name.
#create_relation	Create an association proxy object using the owner and target.
#extension	Get the extension.
#foreign_key_check	Get the name of the method to check if the foreign key has changed.
#foreign_key_setter	The name of the foreign key setter method.
#get_callbacks	Get the callbacks for a given type.
#initialize	Initialize the `::Mongoid::Association`.
#inverse	Get the inverse name.
#inverse_association	Get the inverse's association metadata.
#inverse_class	The class of the object owning this association.
#inverse_class_name	The class name of the object owning this association.
#inverse_klass	Alias for Mongoid::Association::Relatable#inverse_class.
#inverse_setter	The name of the inverse setter method.
#inverse_type	Get the inverse type.
#inverse_type_setter	Gets the setter for the field that sets the type of document on a polymorphic association.
#inverses	Get the inverse names.
#key	The foreign key field if this association stores a foreign key.
#klass	Alias for Mongoid::Association::Relatable#relation_class.
#path	The atomic path for this association.
#relation_class	The class of the association object(s).
#relation_class_name	The class name, possibly unqualified or prefixed, of the association object(s).
#setter	The name of the setter on this object for assigning an associated object.
#type_setter	Get the type setter.
#create_extension!, #default_inverse, #define_autosaver!, #define_builder!, #define_counter_cache_callbacks!, #define_creator!, #define_dependency!, #define_existence_check!, #define_getter!, #define_ids_getter!, #define_ids_setter!, #define_setter!, #define_touchable!,
#inverse_association_classes	Gets the model classes with inverse associations of this model.
#namespace_hierarchy	Returns an array of classes/modules forming the namespace hierarchy where symbols referenced in the provided class/module would be looked up by Ruby.
#polymorph!,
#resolve_name	Resolves the given class/module name in the context of the specified module, as Ruby would when a constant is referenced in the source.
#setup_index!, #validate!

`::Mongoid::Association::Options` - Included

#as	Returns the name of the parent to a polymorphic child.
#dependent	Specify what happens to the associated object when the owner is destroyed.
#inverse_of	The name the owning object uses to refer to this association.
#order	The custom sorting options on the association.
#primary_key	`::Mongoid` assumes that the field used to hold the primary key of the association is id.
#store_as	The store_as option.
#touch_field	The field for saving the associated object's type.
#type	The field for saving the associated object's type.

`::Mongoid::Association::Constrainable` - Included

#convert_to_foreign_key	Convert the supplied object to the appropriate type to set as the foreign key for an association.
#convert_polymorphic

Instance Attribute Details

#embedded? ⇒ `false` (readonly)

Is this association embedded?

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 43


def embedded?
  false
end

#stores_foreign_key? ⇒ `false` (readonly)

Through associations never store a foreign key on the owner document.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 57


def stores_foreign_key?
  false
end

Instance Method Details

#criteria(base) ⇒ Mongoid::Criteria

Return a ::Mongoid::Criteria scoped to the target documents reachable from base via the through association. Performs two queries: one against the intermediate collection, one against the source collection.

Parameters:

base (Document) —
The owner document.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 117


def criteria(base)
  through_crit = through_association.criteria(base)

  crit = if source_association.stores_foreign_key?
           # FK is on the intermediate (e.g. appointment.patient_id -> belongs_to :patient)
           target_pk = source_association.primary_key # '_id' on Patient
           source_fk = source_association.foreign_key # 'patient_id' on Appointment
           source_association.klass.where(
             target_pk => { '$in' => key_values(through_crit, source_fk) }
           )
         else
           # FK is on the source (e.g. reader.book_id -> has_many :readers on Book)
           source_pk = source_association.primary_key # '_id' on intermediate (Book)
           source_fk = source_association.foreign_key # 'book_id' on Reader
           source_association.klass.where(
             source_fk => { '$in' => key_values(through_crit, source_pk) }
           )
         end
  order ? crit.order_by(order) : crit
end

#default_primary_key (private)

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 195


def default_primary_key
  PRIMARY_KEY_DEFAULT
end

#define_readonly_setter! (private)

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 188


def define_readonly_setter!
  assoc = self
  @owner_class.re_define_method(:"#{name}=") do |_object|
    raise Mongoid::Errors::ReadonlyAssociation.new(self.class, assoc)
  end
end

#define_through_getter! (private)

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 169


def define_through_getter!
  assoc = self
  assoc_name = name
  @owner_class.re_define_method(assoc_name) do |reload = false|
    if reload || !instance_variable_defined?("@_#{assoc_name}")
      set_relation(assoc_name, HasManyThrough::Proxy.new(self, assoc))
    end
    instance_variable_get("@_#{assoc_name}")
  end
end

#define_through_ids_getter! (private)

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 180


def define_through_ids_getter!
  assoc_name = name
  ids_method = :"#{assoc_name.to_s.singularize}_ids"
  @owner_class.re_define_method(ids_method) do
    send(assoc_name).pluck(:_id)
  end
end

#key_values(criteria, key) ⇒ Array<Object> (private)

Pluck the given key from the criteria, dropping intermediates that have no value for it. A nil in an $in array matches every document whose queried field is null or absent, which would return documents outside the association. An empty result correctly matches nothing. Mirrors what the eager loader does.

Parameters:

criteria (Mongoid::Criteria) —
The intermediate criteria.
key (String) —
The key to pluck.

Returns:

(Array<Object>) —
The usable key values.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 157


def key_values(criteria, key)
  criteria.pluck(key).compact.uniq
end

#relation ⇒ `Class`

The proxy class for this association type.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 50


def relation
  Proxy
end

#relation_complements ⇒ Array

The list of association complements.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 28


def relation_complements
  [].freeze
end

#setup! ⇒ `self`

Setup instance methods on the owner class.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 35


def setup!
  setup_instance_methods!
  self
end

#setup_instance_methods! (private)

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 161


def setup_instance_methods!
  define_through_getter!
  define_through_ids_getter!
  define_readonly_setter!
  define_existence_check!
  self
end

#source_association ⇒ Mongoid::Association::Relatable

The source association metadata on the intermediate class. Resolved lazily to allow forward references.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 89


def source_association
  @source_association ||= begin
    source_name = (@options[:source] || name.to_s.singularize).to_s
    assoc = through_association.klass.relations[source_name] ||
            raise(
              Errors::InvalidRelationOption.new(
                @owner_class, name, :source, source_name
              )
            )
    if assoc.is_a?(Referenced::HasAndBelongsToMany)
      raise(
        Errors::InvalidRelationOption.new(
          @owner_class, name, :source,
          'has_and_belongs_to_many is not supported as a :through source'
        )
      )
    end
    assoc
  end
end

#through_association ⇒ Mongoid::Association::Relatable

The intermediate association metadata on the owner class. Resolved lazily to allow forward references.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 65


def through_association
  @through_association ||= begin
    assoc = @owner_class.relations[@options[:through].to_s] ||
            raise(
              Errors::InvalidRelationOption.new(
                @owner_class, name, :through, @options[:through]
              )
            )
    if assoc.embedded?
      raise(
        Errors::InvalidRelationOption.new(
          @owner_class, name, :through,
          'through association must be a referenced association, not embedded'
        )
      )
    end
    assoc
  end
end

#validation_default ⇒ `false`

The default for validating the association object.

[ GitHub ]

# File 'lib/mongoid/association/referenced/has_many_through.rb', line 141


def validation_default
  false
end

Class: Mongoid::Association::Referenced::HasManyThrough

Overview

Constant Summary

::Mongoid::Association::Relatable - Included

Instance Attribute Summary

::Mongoid::Association::Relatable - Included

::Mongoid::Association::Options - Included

Instance Method Summary

::Mongoid::Association::Relatable - Included

::Mongoid::Association::Options - Included

::Mongoid::Association::Constrainable - Included

Instance Attribute Details

#embedded? ⇒ false (readonly)

#stores_foreign_key? ⇒ false (readonly)

Instance Method Details

#criteria(base) ⇒ Mongoid::Criteria

#default_primary_key (private)

#define_readonly_setter! (private)

#define_through_getter! (private)

#define_through_ids_getter! (private)

#key_values(criteria, key) ⇒ Array<Object> (private)

#relation ⇒ Class

#relation_complements ⇒ Array

#setup! ⇒ self

#setup_instance_methods! (private)

#source_association ⇒ Mongoid::Association::Relatable

#through_association ⇒ Mongoid::Association::Relatable

#validation_default ⇒ false

`::Mongoid::Association::Relatable` - Included

`::Mongoid::Association::Relatable` - Included

`::Mongoid::Association::Options` - Included

`::Mongoid::Association::Relatable` - Included

`::Mongoid::Association::Options` - Included

`::Mongoid::Association::Constrainable` - Included

#embedded? ⇒ `false` (readonly)

#stores_foreign_key? ⇒ `false` (readonly)

#relation ⇒ `Class`

#setup! ⇒ `self`

#validation_default ⇒ `false`