Class: ActiveFedora::Associations::Association
- Inherits:
-
Object
- Object
- ActiveFedora::Associations::Association
- Defined in:
- lib/active_fedora/associations/association.rb
Overview
This is the root class of all associations:
Association
BelongsToAssociation
AssociationCollection
HasManyAssociation
Direct Known Subclasses
Instance Attribute Summary collapse
-
#owner ⇒ Object
readonly
Returns the value of attribute owner.
-
#reflection ⇒ Object
readonly
Returns the value of attribute reflection.
-
#target ⇒ Object
Returns the value of attribute target.
Instance Method Summary collapse
-
#association_scope ⇒ Object
The scope for this association.
-
#initialize(owner, reflection) ⇒ Association
constructor
A new instance of Association.
-
#load_target ⇒ Object
Loads the target if needed and returns it.
-
#loaded! ⇒ Object
Asserts the target has been loaded setting the loaded flag to
true
. -
#loaded? ⇒ Boolean
Has the target been already loaded?.
-
#reload ⇒ Object
Reloads the target and returns
self
on success. -
#reset ⇒ Object
Resets the loaded flag to
false
and sets the target tonil
. - #scope ⇒ Object
-
#set_inverse_instance(record) ⇒ Object
Set the inverse association, if possible.
-
#stale_target? ⇒ Boolean
The target is stale if the target no longer points to the record(s) that the relevant foreign_key(s) refers to.
-
#target_scope ⇒ Object
Can be overridden (i.e. in ThroughAssociation) to merge in other scopes (i.e. the through association’s scope).
Constructor Details
#initialize(owner, reflection) ⇒ Association
Returns a new instance of Association.
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# File 'lib/active_fedora/associations/association.rb', line 15 def initialize(owner, reflection) #reflection.check_validity! @owner, @reflection = owner, reflection @updated = false reset # construct_scope end |
Instance Attribute Details
#owner ⇒ Object (readonly)
Returns the value of attribute owner.
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# File 'lib/active_fedora/associations/association.rb', line 12 def owner @owner end |
#reflection ⇒ Object (readonly)
Returns the value of attribute reflection.
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# File 'lib/active_fedora/associations/association.rb', line 12 def reflection @reflection end |
#target ⇒ Object
Returns the value of attribute target.
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# File 'lib/active_fedora/associations/association.rb', line 12 def target @target end |
Instance Method Details
#association_scope ⇒ Object
The scope for this association.
Note that the association_scope is merged into the target_scope only when the scope method is called. This is because at that point the call may be surrounded by scope.scoping { … } or with_scope { … } etc, which affects the scope which actually gets built.
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# File 'lib/active_fedora/associations/association.rb', line 74 def association_scope if klass @association_scope ||= AssociationScope.new(self).scope end end |
#load_target ⇒ Object
Loads the target if needed and returns it.
This method is abstract in the sense that it relies on find_target
, which is expected to be provided by descendants.
If the target is already loaded it is just returned. Thus, you can call load_target
unconditionally to get the target.
ActiveFedora::ObjectNotFoundError is rescued within the method, and it is not reraised. The proxy is reset and nil
is the return value.
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# File 'lib/active_fedora/associations/association.rb', line 105 def load_target @target = find_target if (@stale_state && stale_target?) || find_target? loaded! unless loaded? target end |
#loaded! ⇒ Object
Asserts the target has been loaded setting the loaded flag to true
.
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# File 'lib/active_fedora/associations/association.rb', line 43 def loaded! @loaded = true @stale_state = stale_state end |
#loaded? ⇒ Boolean
Has the target been already loaded?
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# File 'lib/active_fedora/associations/association.rb', line 38 def loaded? @loaded end |
#reload ⇒ Object
Reloads the target and returns self
on success.
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# File 'lib/active_fedora/associations/association.rb', line 30 def reload reset # construct_scope load_target self unless @target.nil? end |
#reset ⇒ Object
Resets the loaded flag to false
and sets the target to nil
.
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# File 'lib/active_fedora/associations/association.rb', line 24 def reset @loaded = false @target = nil end |
#scope ⇒ Object
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# File 'lib/active_fedora/associations/association.rb', line 64 def scope target_scope.merge(association_scope) end |
#set_inverse_instance(record) ⇒ Object
Set the inverse association, if possible
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# File 'lib/active_fedora/associations/association.rb', line 81 def set_inverse_instance(record) if record && invertible_for?(record) inverse = record.association(inverse_reflection_for(record).name) inverse.target = owner end end |
#stale_target? ⇒ Boolean
The target is stale if the target no longer points to the record(s) that the relevant foreign_key(s) refers to. If stale, the association accessor method on the owner will reload the target. It’s up to subclasses to implement the state_state method if relevant.
Note that if the target has not been loaded, it is not considered stale.
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# File 'lib/active_fedora/associations/association.rb', line 54 def stale_target? loaded? && @stale_state != stale_state end |
#target_scope ⇒ Object
Can be overridden (i.e. in ThroughAssociation) to merge in other scopes (i.e. the through association’s scope)
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# File 'lib/active_fedora/associations/association.rb', line 91 def target_scope klass.all end |