HYC-1354 - Fallback Thumbnails (#1133)

* avoid loading overrides multiple times using load

* fallback to member ids if representative isnt there

* thumbnail presenter override

* accounting for nested solr documents, commenting out some stuff

* thumbnail presenter tests

* test for rescue block in representative_presenter

* shared delegates module

app/overrides/presenters/blacklight/thumbnail_presenter_override.rb

@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+# https://github.com/projectblacklight/blacklight/blob/v8.7.0/app/presenters/blacklight/thumbnail_presenter.rb
+module Blacklight
+  class ThumbnailPresenter
+    private
+    # [hyc-override] Retrieve the thumbnail of the first file_set of any given work instead of using the default if it exists
+    def retrieve_values(field_config)
+      # Return the default thumbnail if the document object is nil
+      unless document
+        return FieldRetriever.new(document, field_config, view_context).fetch
+      end
+
+      solr_doc = extract_solr_document(document)
+      document_hash = solr_doc.to_h
+
+      # Update the `thumbnail_path_ss` dynamically if needed
+      if needs_thumbnail_path_update?(document_hash)
+        file_set_id = document_hash['file_set_ids_ssim']&.first
+        document_hash['thumbnail_path_ss'] = "/downloads/#{file_set_id}?file=thumbnail"
+        Rails.logger.info("Updated thumbnail_path_ss: #{document_hash['thumbnail_path_ss']} for work with id #{document_hash['id']}")
+        # Create a temporary SolrDocument from the updated hash
+        updated_document = SolrDocument.new(document_hash)
+        FieldRetriever.new(updated_document, field_config, view_context).fetch
+      else
+        FieldRetriever.new(solr_doc, field_config, view_context).fetch
+      end
+    end
+
+    # Extract the SolrDocument from the document object if it's nested
+    # Prevents errors when the document object is a presenter on work show pages
+    def extract_solr_document(doc)
+      if doc.is_a?(SolrDocument)
+        doc
+      elsif doc.respond_to?(:solr_document) && doc.solr_document.is_a?(SolrDocument)
+        doc.solr_document
+      end
+    end
+
+    def needs_thumbnail_path_update?(document)
+      thumbnail_path = document['thumbnail_path_ss'] || ''
+      file_set_ids = document['file_set_ids_ssim']
+      thumbnail_missing_or_default = thumbnail_path.blank? || thumbnail_path !~ %r{^/downloads/\w+\?file=thumbnail$}
+
+      # Returns true if file_set_ids are present and the thumbnail path is the default or missing entirely
+      file_set_ids.present? && thumbnail_missing_or_default
+    end
+  end
+  end

app/overrides/presenters/hyrax/work_show_presenter_override.rb

@@ -2,16 +2,33 @@
 # [hyc-override] Overriding helper in order to add doi to citation
 # https://github.com/samvera/hyrax/blob/hyrax-v4.0.0/app/presenters/hyrax/work_show_presenter.rb
 Hyrax::WorkShowPresenter.class_eval do
-  # delegating just :doi seems to exclude the other fields, so pull all fields in from original file
-  delegate :title, :date_created, :date_issued, :description, :doi, :creator, :place_of_publication,
-           :creator_display, :contributor, :subject, :publisher, :language, :embargo_release_date,
-           :lease_expiration_date, :license, :source, :rights_statement, :thumbnail_id, :representative_id,
-           :rendering_ids, :member_of_collection_ids, :alternative_title, :bibliographic_citation, to: :solr_document
+  include Hyrax::SharedDelegates
 
   # [hyc-override] Add default scholarly? method
   # Indicates if the work is considered scholarly according to google scholar
   # This method is not defined in hyrax, but it is referenced by GoogleScholarPresenter
   def scholarly?
     false
   end
+
+  def fetch_primary_fileset_id
+    res = representative_id.blank? ? member_ids.first : representative_id
+    res
+  end
+
+  # [hyc-override] Use a work's first related fileset_id instead of the representative_id if it's nil
+  # @return FileSetPresenter presenter for the representative FileSets
+  def representative_presenter
+    @representative_presenter ||=
+      begin
+        primary_fileset_id = fetch_primary_fileset_id
+        return nil if primary_fileset_id.blank?
+        result = member_presenters([primary_fileset_id]).first
+        return nil if result.try(:id) == id
+        result.try(:representative_presenter) || result
+      rescue Hyrax::ObjectNotFoundError
+        Hyrax.logger.warn "Unable to find representative_id #{primary_fileset_id} for work #{id}"
+        return nil
+      end
+  end
 end

app/presenters/hyrax/data_set_presenter.rb

@@ -3,11 +3,7 @@
 #  `rails generate hyrax:work DataSet`
 module Hyrax
   class DataSetPresenter < Hyrax::WorkShowPresenter
-    delegate :abstract, :admin_note, :contributor_display, :copyright_date, :creator_display, :date_issued, :dcmi_type, :deposit_record, :doi,
-             :extent, :funder, :kind_of_data, :last_modified_date, :language_label,
-             :license_label, :methodology, :note, :orcid_label, :other_affiliation_label, :project_director_display, :researcher_display,
-             :rights_holder, :rights_statement_label, :sponsor, to: :solr_document
-
+    include Hyrax::SharedDelegates
     # See: WorkShowPresenter.scholarly?
     def scholarly?
       true

app/presenters/hyrax/shared_delegates.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+module Hyrax
+  module SharedDelegates
+    extend ActiveSupport::Concern
+    included do
+      delegate :abstract, :admin_note, :alternative_title, :bibliographic_citation, :contributor, :contributor_display, :copyright_date,
+             :creator, :creator_display, :date_created, :date_issued, :dcmi_type, :deposit_record, :description, :doi, :embargo_release_date,
+             :extent, :funder, :human_readable_type, :identifier, :itemtype, :kind_of_data, :language, :language_label, :last_modified_date,
+             :lease_expiration_date, :license, :license_label, :member_ids, :member_of_collection_ids, :methodology, :note, :orcid_label,
+             :other_affiliation_label, :place_of_publication, :project_director_display, :publisher, :related_url, :rendering_ids, :representative_id, :researcher_display,
+             :resource_type, :rights_holder, :rights_notes, :rights_statement, :rights_statement_label, :sponsor, :source, :subject,
+             :thumbnail_id, :title, to: :solr_document
+    end
+  end
+  end

app/views/hyrax/base/_representative_media.html.erb

@@ -0,0 +1,12 @@
+<%# [hyc-override] https://github.com/samvera/hyrax/tree/hyrax-v4.0.0/app/views/hyrax/base/_representative_media.html.erb %>
+<%# [hyc-override] Use custom function fetch_primary_fileset_id in place of representative_id %>
+<!-- This renders the thumbnail for first file set associated with a work instead of the default in case the representative_id is nil. (Typically occurs after deleting the first file attached to a work) -->
+<% if presenter.fetch_primary_fileset_id.present? && presenter.representative_presenter.present? %>
+  <% if defined?(viewer) && viewer %>
+    <%= iiif_viewer_display presenter %>
+  <% else %>
+    <%= render media_display_partial(presenter.representative_presenter), file_set: presenter.representative_presenter  %>
+  <% end %>
+<% else %>
+  <%= image_tag 'default.png', class: "canonical-image", alt: 'default representative image' %>
+<% end %>

app/views/hyrax/base/_show_actions.html.erb

@@ -41,7 +41,7 @@
   <div class="col-sm-6 text-right">
     <% if presenter.editor? && !workflow_restriction?(presenter) %>
       <%= link_to t('.edit'), edit_polymorphic_path([main_app, presenter]), class: 'btn btn-secondary' %>
-      <% if presenter.member_count > 1 %>
+      <% if presenter.member_count > 0 %>
           <%= link_to t("hyrax.file_manager.link_text"), polymorphic_path([main_app, :file_manager, presenter]), class: 'btn btn-secondary' %>
       <% end %>
       <% if presenter.valid_child_concerns.length > 0 %>

config/application.rb

@@ -45,7 +45,7 @@ class Application < Rails::Application
     overrides = "#{Rails.root}/app/overrides"
     config.to_prepare do
       Dir.glob("#{overrides}/**/*_override.rb").sort.each do |c|
-        Rails.configuration.cache_classes ? require(c) : load(c)
+        Rails.configuration.cache_classes ? require(c) : require_dependency(c)
       end
     end
 

spec/presenters/blacklight/thumbnail_presenter_spec.rb

@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+require 'rails_helper'
+require Rails.root.join('app/overrides/presenters/blacklight/thumbnail_presenter_override.rb')
+
+RSpec.describe Blacklight::ThumbnailPresenter do
+  describe '#retrieve_values' do
+    it 'does not attempt to process a solr document if it is nil' do
+      # Mock field config and view context
+      field_config = double('FieldConfig')
+      view_context = double('ViewContext')
+      presenter = Blacklight::ThumbnailPresenter.new(nil, view_context, field_config)
+
+      retriever_instance = Blacklight::FieldRetriever.new(nil, nil, nil)
+      allow(Blacklight::FieldRetriever).to receive(:new).and_return(retriever_instance)
+      allow(retriever_instance).to receive(:fetch).and_return('default_thumbnail')
+      allow(presenter).to receive(:extract_solr_document)
+
+      result = presenter.send(:retrieve_values, field_config)
+      expect(Blacklight::FieldRetriever).to have_received(:new).with(nil, field_config, view_context)
+      # Presenter should not process the document if it's nil
+      expect(presenter).not_to have_received(:extract_solr_document)
+      expect(result).to eq('default_thumbnail')
+    end
+
+    it 'updates the thumbnail_path_ss if it needs an update' do
+      field_config = double('FieldConfig')
+      view_context = double('ViewContext')
+      retriever_instance = Blacklight::FieldRetriever.new(nil, nil, nil)
+      document_hash = {
+        'thumbnail_path_ss' => '/assets/work-default.png',
+        'file_set_ids_ssim' => ['file_set_1'],
+        'id' => '1'
+      }
+      solr_doc = SolrDocument.new(document_hash)
+      presenter = Blacklight::ThumbnailPresenter.new(solr_doc, view_context, field_config)
+
+      allow(presenter).to receive(:needs_thumbnail_path_update?).and_return(true)
+      allow(SolrDocument).to receive(:new).and_return(instance_double(SolrDocument))
+      allow(Blacklight::FieldRetriever).to receive(:new).and_return(retriever_instance)
+      allow(retriever_instance).to receive(:fetch).and_return('updated_thumbnail')
+      allow(Rails.logger).to receive(:info)
+
+      result = presenter.send(:retrieve_values, field_config)
+      expect(Rails.logger).to have_received(:info).with('Updated thumbnail_path_ss: /downloads/file_set_1?file=thumbnail for work with id 1')
+      expect(SolrDocument).to have_received(:new).with(
+        hash_including('thumbnail_path_ss' => '/downloads/file_set_1?file=thumbnail')
+      )
+      expect(result).to eq('updated_thumbnail')
+    end
+  end
+end

spec/presenters/hyrax/work_show_presenter_spec.rb

@@ -37,4 +37,20 @@
   it { is_expected.to delegate_method(:resource_type).to(:solr_document) }
   it { is_expected.to delegate_method(:keyword).to(:solr_document) }
   it { is_expected.to delegate_method(:itemtype).to(:solr_document) }
+
+  describe '#representative_presenter' do
+    context 'when member_presenters raises a Hyrax::ObjectNotFoundError' do
+      before do
+        allow(presenter).to receive(:fetch_primary_fileset_id).and_return('file_set_id_1')
+        allow(presenter).to receive(:member_presenters).and_raise(Hyrax::ObjectNotFoundError)
+        allow(Hyrax.logger).to receive(:warn)
+      end
+
+      it 'logs a warning and returns nil' do
+        result = presenter.representative_presenter
+        expect(Hyrax.logger).to have_received(:warn).with('Unable to find representative_id file_set_id_1 for work 888888')
+        expect(result).to be_nil
+      end
+    end
+  end
 end