Merge pull request #2416 from sul-dlss/import-public-xml-record

Make the PublicXmlRecord local

app/models/public_xml_record.rb

@@ -0,0 +1,181 @@
+# frozen_string_literal: true
+
+# Retrieves and represents the public xml file from PURL
+class PublicXmlRecord # rubocop:disable Metrics/ClassLength
+  attr_reader :druid, :options
+
+  COLLECTION_TYPES = %w(collection set).freeze
+
+  def self.fetch(url)
+    response = HTTP.get(url)
+    response.body if response.status.ok?
+  end
+
+  def initialize(druid, options = {})
+    @druid = druid
+    @options = options
+  end
+
+  def searchworks_id
+    catkey.nil? ? druid : catkey
+  end
+
+  # @return catkey value from the DOR identity_metadata, or nil if there is no catkey
+  def catkey
+    get_value(public_xml_doc.xpath("/publicObject/identityMetadata/otherId[@name='catkey']"))
+  end
+
+  # @return objectLabel value from the DOR identity_metadata, or nil if there is no barcode
+  def label
+    get_value(public_xml_doc.xpath('/publicObject/identityMetadata/objectLabel'))
+  end
+
+  def get_value(node)
+    node&.first ? node.first.content : nil
+  end
+
+  def stanford_mods
+    @stanford_mods ||= Stanford::Mods::Record.new.tap do |smods_rec|
+      smods_rec.from_str(mods.to_s)
+    end
+  end
+
+  def mods_display
+    @mods_display ||= ModsDisplay::HTML.new(stanford_mods)
+  end
+
+  def public_xml
+    @public_xml ||= self.class.fetch("#{purl_base_url}.xml")
+  end
+
+  def public_xml?
+    !!public_xml
+  end
+
+  def public_xml_doc
+    @public_xml_doc ||= Nokogiri::XML(public_xml)
+  end
+
+  def mods
+    @mods ||= if public_xml_doc.xpath('/publicObject/mods:mods', mods: 'http://www.loc.gov/mods/v3').any?
+                public_xml_doc.xpath('/publicObject/mods:mods', mods: 'http://www.loc.gov/mods/v3').first
+              else
+                if defined?(Honeybadger)
+                  Honeybadger.notify(
+                    'Unable to find MODS in the public xml; falling back to stand-alone mods document',
+                    context: { druid: druid }
+                  )
+                end
+
+                Nokogiri::XML(self.class.fetch("#{purl_base_url}.mods"))
+              end
+  end
+
+  # @return true if the identityMetadata has <objectType>collection</objectType>, false otherwise
+  def collection?
+    object_type_nodes = public_xml_doc.xpath('//objectType')
+    object_type_nodes.find_index { |n| COLLECTION_TYPES.include? n.text.downcase }
+  end
+
+  # value is used to tell SearchWorks UI app of specific display needs for objects
+  # this comes from the <thumb> element in publicXML or the first image found (as parsed by discovery-indexer)
+  # @return [String] filename or nil if none found
+  def thumb
+    return if collection?
+
+    encoded_thumb if %w(book image manuscript map webarchive-seed).include?(dor_content_type)
+  end
+
+  # the value of the type attribute for a DOR object's contentMetadata
+  #  more info about these values is here:
+  #    https://consul.stanford.edu/display/chimera/DOR+content+types%2C+resource+types+and+interpretive+metadata
+  #    https://consul.stanford.edu/display/chimera/Summary+of+Content+Types%2C+Resource+Types+and+their+behaviors
+  # @return [String]
+  def dor_content_type
+    public_xml_doc.xpath('//contentMetadata/@type').text
+  end
+
+  # the thumbnail in publicXML, falling back to the first image if no thumb node is found
+  # @return [String] thumb filename with druid prepended, e.g. oo000oo0001/filename withspace.jp2
+  def parse_thumb
+    return if public_xml_doc.nil?
+
+    thumb = public_xml_doc.xpath('//thumb')
+    # first try and parse what is in the thumb node of publicXML, but fallback to the first image if needed
+    if thumb.size == 1
+      thumb.first.content
+    elsif thumb.empty? && parse_sw_image_ids.size.positive?
+      parse_sw_image_ids.first
+    end
+  end
+
+  # the druid and id attribute of resource/file and objectId and fileId of the
+  # resource/externalFile elements that match the image, page, or thumb resource type, including extension
+  # Also, prepends the corresponding druid and / specifically for Searchworks use
+  # @return [Array<String>] filenames
+  def parse_sw_image_ids
+    public_xml_doc.xpath('//resource[@type="page" or @type="image" or @type="thumb"]').map do |node|
+      node.xpath('./file[@mimetype="image/jp2"]/@id').map do |x|
+        "#{@druid.gsub('druid:', '')}/" + x
+      end << node.xpath('./externalFile[@mimetype="image/jp2"]').map do |y|
+               "#{y.attributes['objectId'].text.split(':').last}/#{y.attributes['fileId']}"
+             end
+    end.flatten
+  end
+
+  def collections
+    @collections ||= predicate_druids('isMemberOfCollection').map do |druid|
+      PublicXmlRecord.new(druid, options)
+    end
+  end
+
+  def constituents
+    @constituents ||= predicate_druids('isConstituentOf').map do |druid|
+      PublicXmlRecord.new(druid, options)
+    end
+  end
+
+  def items
+    return [] unless collection?
+
+    purl_fetcher_client.collection_members(druid)
+  end
+
+  # the thumbnail in publicXML properly URI encoded, including the slash separator
+  # @return [String] thumb filename with druid prepended, e.g. oo000oo0001%2Ffilename%20withspace.jp2
+  def encoded_thumb
+    thumb = parse_thumb
+    return unless thumb
+
+    thumb_druid = thumb.split('/').first # the druid (before the first slash)
+    thumb_filename = thumb.split(%r{[a-zA-Z]{2}[0-9]{3}[a-zA-Z]{2}[0-9]{4}[/]}).last # everything after the druid
+    "#{thumb_druid}%2F#{ERB::Util.url_encode(thumb_filename)}"
+  end
+
+  # get the druids from predicate relationships in rels-ext from public_xml
+  # @return [Array<String>, nil] the druids (e.g. ww123yy1234) from the rdf:resource of the predicate relationships,
+  #                              or nil if none
+  def predicate_druids(predicate, predicate_ns = 'info:fedora/fedora-system:def/relations-external#')
+    ns_hash = { 'rdf' => 'http://www.w3.org/1999/02/22-rdf-syntax-ns#', 'pred_ns' => predicate_ns }
+    xpth = "/publicObject/rdf:RDF/rdf:Description/pred_ns:#{predicate}/@rdf:resource"
+    pred_nodes = public_xml_doc.xpath(xpth, ns_hash)
+    pred_nodes.reject { |n| n.value.empty? }.map do |n|
+      n.value.split('druid:').last
+    end
+  end
+
+  def purl_base_url
+    format(Settings.purl.url, druid:)
+  end
+
+  def purl_fetcher_api_endpoint
+    Settings.purl_fetcher.url
+  end
+
+  def purl_fetcher_client
+    @purl_fetcher_client ||= PurlFetcher::Client::Reader.new(
+      nil, # TODO: Remove for purl_fetcher-client 1.0
+      'purl_fetcher.api_endpoint' => purl_fetcher_api_endpoint
+    )
+  end
+end

app/models/purl.rb

@@ -15,20 +15,10 @@ def exists?
     false
   end
 
-  def collection?
-    public_xml_record.is_collection
-  end
-
-  delegate :items, to: :public_xml_record
+  delegate :items, :collection?, to: :public_xml_record
 
   def public_xml_record
-    @public_xml_record ||= begin
-      PurlFetcher::Client::PublicXmlRecord.new(
-        bare_druid,
-        purl_url: format(Settings.purl.url, druid: ''),
-        purl_fetcher_url: Settings.purl_fetcher.url
-      )
-    end
+    @public_xml_record ||= PublicXmlRecord.new(bare_druid)
   end
 
   def bare_druid