Class: RDF::LDP::IndirectContainer

Inherits:
DirectContainer show all
Defined in:
lib/rdf/ldp/indirect_container.rb

Overview

An extension of ‘RDF::LDP::DirectContainer` implementing indirect containment. Adds the concept of an inserted content relation to the features of the direct container.

Clients MUST provide exactly one ‘ldp:insertedContentRelation` statement in each Indirect Container. If no `#inserted_content_relation` is given by the client, we default to `ldp:MemberSubject`. If more than one is present,

Attempts to POST resources without the appropriate content relation (or with more than one) to an Indirect Container will fail with ‘Not Acceptable`. LDP-NR’s cannot be added since indirect membership is not well defined for them, per _LDP 5.5.1.2_.

See Also:

Constant Summary collapse

INSERTED_CONTENT_REL_URI = 
RDF::Vocab::LDP.insertedContentRelation.freeze
MEMBER_SUBJECT_URI = 
RDF::Vocab::LDP.MemberSubject.freeze

Constants inherited from DirectContainer

DirectContainer::MEMBERSHIP_RESOURCE_URI, DirectContainer::MEMBER_URI, DirectContainer::RELATION_TERMS

Constants inherited from Resource

Resource::CONTAINS_URI, Resource::INVALIDATED_AT_URI, Resource::MODIFIED_URI

Instance Attribute Summary

Attributes inherited from Resource

#metagraph, #subject_uri

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from DirectContainer

#add, #make_membership_triple, #membership_constant_uri, #membership_predicate, #remove

Methods inherited from Container

#add, #add_containment_triple, #container?, #containment_triples, #has_containment_triple?, #make_containment_triple, #remove, #remove_containment_triple, #update

Methods inherited from RDFSource

#destroy, #graph, #initialize, #rdf_source?, #to_response, #update

Methods inherited from Resource

#allowed_methods, #container?, #containers, #destroy, #destroyed?, #etag, #exists?, find, gen_id, #initialize, interaction_model, #last_modified, #ldp_resource?, #match?, metagraph_name, #non_rdf_source?, #rdf_source?, #request, #to_response, #to_uri, #update

Constructor Details

This class inherits a constructor from RDF::LDP::RDFSource

Class Method Details

.to_uri ⇒ Object 



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# File 'lib/rdf/ldp/indirect_container.rb', line 24

def self.to_uri
  RDF::Vocab::LDP.IndirectContainer
end

Instance Method Details

#container_class ⇒ RDF::URI

Returns a URI representing the container type.

Returns:

  • (RDF::URI) —

    a URI representing the container type



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# File 'lib/rdf/ldp/indirect_container.rb', line 30

def container_class
  CONTAINER_CLASSES[:indirect]
end

#create(input, content_type) ⇒ Object

Creates and inserts default relation triples if none are given.

See Also:



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# File 'lib/rdf/ldp/indirect_container.rb', line 39

def create(input, content_type)
  super

  graph.transaction(mutable: true) do |tx|
    if inserted_content_statements.empty?
      tx.insert RDF::Statement(subject_uri,
                               INSERTED_CONTENT_REL_URI,
                               MEMBER_SUBJECT_URI)
    end
  end

  self
end

#inserted_content_relation ⇒ RDF::URI

Gives the inserted content relation for the indirect container. If none is present in the container state, we add ‘ldp:MemberSubject`, effectively treating this LDP-IC as an LDP-DC.

Returns:

  • (RDF::URI) —

    the inserted content relation; either a predicate term or ‘ldp:MemberSubject`

Raises:

See Also:



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# File 'lib/rdf/ldp/indirect_container.rb', line 65

def inserted_content_relation
  statements = inserted_content_statements
  return statements.first.object if statements.count == 1

  raise(NotAcceptable, 'An LDP-IC MUST have exactly ' \
                       'one inserted content relation triple; found ' \
                       "#{statements.count}.")
end