Module: ActiveFedora::NamedRelationships

Extended by:
ActiveSupport::Concern, Deprecation
Defined in:
lib/active_fedora/named_relationships.rb

Instance Method Summary collapse

Instance Method Details

#create_bidirectional_named_relationship_methods(name, outbound_name) ⇒ Object

** EXPERIMENTAL **

Similar to +create_named_relationship_methods+ except we are merely creating an alias for outbound portion of bidirectional

====Example
  has_bidirectional_relationship "members", :has_collection_member, :is_member_of_collection

  Method members_outbound_append and members_outbound_remove added
  This method will create members_append which does same thing as members_outbound_append
  and will create members_remove which does same thing as members_outbound_remove



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# File 'lib/active_fedora/named_relationships.rb', line 89

def create_bidirectional_named_relationship_methods(name,outbound_name)
  append_method_name = "#{name.to_s.downcase}_append"
  remove_method_name = "#{name.to_s.downcase}_remove"
  self.send(:define_method,:"#{append_method_name}") {|object| add_named_relationship(outbound_name,object)}
  self.send(:define_method,:"#{remove_method_name}") {|object| remove_named_relationship(outbound_name,object)}
end

#create_named_relationship_methods(name) ⇒ Object

** EXPERIMENTAL **

Used in has_relationship call to create dynamic helper methods to append and remove objects to and from a named relationship

Example

For the following relationship

has_relationship "audio_records", :has_part, :type=>AudioRecord

Methods audio_records_append and audio_records_remove are created. Boths methods take an object that is kind_of? ActiveFedora::Base as a parameter



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# File 'lib/active_fedora/named_relationships.rb', line 73

def create_named_relationship_methods(name)
  append_method_name = "#{name.to_s.downcase}_append"
  remove_method_name = "#{name.to_s.downcase}_remove"
  self.send(:define_method,:"#{append_method_name}") {|object| add_named_relationship(name,object)}
  self.send(:define_method,:"#{remove_method_name}") {|object| remove_named_relationship(name,object)}
end

#named_predicate_exists_with_different_name?(subject, name, predicate) ⇒ Boolean

** EXPERIMENTAL **

Check to make sure a subject,name, and predicate triple does not already exist with the same subject but different name. This method is used to ensure conflicting has_relationship calls are not made because predicates cannot be reused across relationship names. Otherwise, the mapping of relationship name to predicate in RELS-EXT would be broken.

Returns:

  • (Boolean) 


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# File 'lib/active_fedora/named_relationships.rb', line 19

def named_predicate_exists_with_different_name?(subject,name,predicate)
  if named_relationships_desc.has_key?(subject)
    named_relationships_desc[subject].each_pair do |existing_name, args|
      return true if !args[:predicate].nil? && args[:predicate] == predicate && existing_name != name 
    end
  end
  return false
end

#named_relationships_desc ⇒ Object

** EXPERIMENTAL **

Return hash that stores named relationship metadata defined by has_relationship calls

Example

For the following relationship

has_relationship "audio_records", :has_part, :type=>AudioRecord

Results in the following returned by named_relationships_desc

{:self=>{"audio_records"=>{:type=>AudioRecord, :singular=>nil, :predicate=>:has_part, :inbound=>false}}}



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# File 'lib/active_fedora/named_relationships.rb', line 37

def named_relationships_desc
  @class_named_relationships_desc ||= Hash[:self => {}]
  #class_named_relationships_desc
end

#register_named_relationship(subject, name, predicate, opts) ⇒ Object

** EXPERIMENTAL **

Internal method that adds relationship name and predicate pair to either an outbound (:self) or inbound (:inbound) relationship types.



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# File 'lib/active_fedora/named_relationships.rb', line 56

def register_named_relationship(subject, name, predicate, opts)
  register_named_subject(subject)
  opts.merge!({:predicate=>predicate})
  named_relationships_desc[subject][name] = opts
end

#register_named_subject(subject) ⇒ Object

** EXPERIMENTAL **

Internal method that ensures a relationship subject such as :self and :inbound exist within the named_relationships_desc hash tracking named relationships metadata.



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# File 'lib/active_fedora/named_relationships.rb', line 46

def register_named_subject(subject)
  unless named_relationships_desc.has_key?(subject) 
    named_relationships_desc[subject] = {} 
  end
end