Move PublishedRelationshipsFilter from dor-services

sul-dlss · Apr 24, 2019 · 2215a58 · 2215a58
1 parent 04d84bc
commit 2215a58
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Showing 3 changed files with 102 additions and 3 deletions.
diff --git a/app/services/public_xml_service.rb b/app/services/public_xml_service.rb
@@ -16,8 +16,7 @@ def to_xml
     pub.add_child(public_identity_metadata.root) # add in modified identityMetadata datastream
     pub.add_child(public_content_metadata.root) if public_content_metadata.xpath('//resource').any?
     pub.add_child(public_rights_metadata.root)
-
-    pub.add_child(public_relationships.root) unless public_relationships.nil? # TODO: Should never be nil in practice; working around an ActiveFedora quirk for testing
+    pub.add_child(public_relationships.root)
     pub.add_child(DublinCoreService.new(object).ng_xml.root)
     pub.add_child(Dor::PublicDescMetadataService.new(object).ng_xml.root)
     pub.add_child(release_xml.root) unless release_xml.xpath('//release').children.empty? # If there are no release_tags, this prevents an empty <releaseData/> from being added
@@ -48,7 +47,7 @@ def release_xml
   end
 
   def public_relationships
-    @public_relationships ||= object.public_relationships.clone
+    PublishedRelationshipsFilter.new(object).xml
   end
 
   def public_rights_metadata

diff --git a/app/services/published_relationships_filter.rb b/app/services/published_relationships_filter.rb
@@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+# Show the relationships that are publically available
+# removes things like hydra:isGovernedBy and fedora-model:hasModel
+class PublishedRelationshipsFilter
+  INCLUDE_ELEMENTS = ['fedora:isMemberOf', 'fedora:isMemberOfCollection', 'fedora:isConstituentOf'].freeze
+  NAMESPACE = { 'rdf' => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#' }.freeze
+
+  # @param [Dor::Abstract] object
+  def initialize(object)
+    @obj = object
+  end
+
+  def xml
+    relationships_ng_xml do |rels_doc|
+      statements(rels_doc).each do |rel|
+        next if keep?(rel.namespace.prefix, rel.name)
+
+        rel.next_sibling.remove if rel.next_sibling.content.strip.empty?
+        rel.remove
+      end
+    end
+  end
+
+  private
+
+  attr_reader :obj
+
+  def statements(rels_doc)
+    rels_doc.xpath('/rdf:RDF/rdf:Description/*', NAMESPACE)
+  end
+
+  def keep?(prefix, name)
+    INCLUDE_ELEMENTS.include?([prefix, name].join(':'))
+  end
+
+  # This creates a duplicate of RELS-EXT and yields it to the block
+  def relationships_ng_xml
+    duplicate_rels_ext.tap do |ng_xml|
+      yield(ng_xml)
+    end
+  end
+
+  def duplicate_rels_ext
+    Nokogiri::XML(obj.datastreams['RELS-EXT'].content)
+  end
+end
diff --git a/spec/services/published_relationships_filter_spec.rb b/spec/services/published_relationships_filter_spec.rb
@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe PublishedRelationshipsFilter do
+  subject(:service) { described_class.new(obj) }
+
+  let(:obj) { instantiate_fixture('druid:ab123cd4567', Dor::Item) }
+
+  describe '#xml' do
+    subject(:doc) { service.xml }
+
+    context 'with isMemberOfCollection and isConstituentOf relationships' do
+      let(:relationships) do
+        <<~EOXML
+          <rdf:RDF xmlns:fedora-model="info:fedora/fedora-system:def/model#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:fedora="info:fedora/fedora-system:def/relations-external#" xmlns:hydra="http://projecthydra.org/ns/relations#">
+            <rdf:Description rdf:about="info:fedora/druid:ab123cd4567">
+              <hydra:isGovernedBy rdf:resource="info:fedora/druid:789012"></hydra:isGovernedBy>
+              <fedora-model:hasModel rdf:resource="info:fedora/hydra:commonMetadata"></fedora-model:hasModel>
+              <fedora:isMemberOf rdf:resource="info:fedora/druid:xh235dd9059"></fedora:isMemberOf>
+              <fedora:isMemberOfCollection rdf:resource="info:fedora/druid:xh235dd9059"></fedora:isMemberOfCollection>
+              <fedora:isConstituentOf rdf:resource="info:fedora/druid:hj097bm8879"></fedora:isConstituentOf>
+            </rdf:Description>
+          </rdf:RDF>
+        EOXML
+      end
+
+      let(:expected) do
+        <<~XML
+          <?xml version="1.0"?>
+            <rdf:RDF xmlns:fedora-model="info:fedora/fedora-system:def/model#" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:fedora="info:fedora/fedora-system:def/relations-external#" xmlns:hydra="http://projecthydra.org/ns/relations#">
+              <rdf:Description rdf:about="info:fedora/druid:ab123cd4567">
+                <fedora:isMemberOf rdf:resource="info:fedora/druid:xh235dd9059"/>
+                <fedora:isMemberOfCollection rdf:resource="info:fedora/druid:xh235dd9059"/>
+                <fedora:isConstituentOf rdf:resource="info:fedora/druid:hj097bm8879"/>
+              </rdf:Description>
+            </rdf:RDF>
+        XML
+      end
+
+      before do
+        ActiveFedora::RelsExtDatastream.from_xml(relationships, obj.rels_ext)
+        # Needed to generate the Datastream#content
+        obj.object_relations.dirty = true
+        obj.rels_ext.serialize!
+      end
+
+      it 'discards the non-allowed relations' do
+        expect(doc).to be_equivalent_to expected
+      end
+    end
+  end
+end