Revert "removes an override we don't need in hyrax 3 (#107)"

This reverts commit 5b64eeb.

app/models/concerns/hyrax/collection_nesting.rb

@@ -0,0 +1,90 @@
+# frozen_string_literal: true
+module Hyrax
+  # Responsible for adding the necessary callbacks for updating the nested collection information
+  # This is part of the after update index because it is a potentially very expensive process.
+  #
+  # @todo Consider extracting the update_index callback to ActiveFedora::Base
+  # rubocop:disable Metrics/BlockLength
+  module CollectionNesting
+    extend ActiveSupport::Concern
+
+    included do
+      extend ActiveModel::Callbacks
+      include ActiveModel::Validations::Callbacks
+
+      define_model_callbacks :update_index, only: :after
+      after_update_index :update_nested_collection_relationship_indices
+      after_destroy :update_child_nested_collection_relationship_indices
+      before_save :before_update_nested_collection_relationship_indices
+      after_save :after_update_nested_collection_relationship_indices
+
+      def before_update_nested_collection_relationship_indices
+        @during_save = true
+      end
+
+      def after_update_nested_collection_relationship_indices
+        @during_save = false
+        reindex_nested_relationships_for(id: id, extent: reindex_extent)
+        # rubocop:disable Style/GuardClause
+        if self.class.to_s == "Collection"
+          children = find_children_of(destroyed_id: id)
+          ids = []
+          children.each do |child|
+            ids << child.id
+          end
+
+          begin
+            IndexChildrenJob.perform_later(ids)
+          rescue ActiveJob::Uniqueness::JobNotUnique
+            Rails.logger.warn "Tried to queue non-unique IndexChildren job for #{ids}"
+          end
+        end
+      end
+
+      def update_nested_collection_relationship_indices
+        return if @during_save
+        reindex_nested_relationships_for(id: id, extent: reindex_extent)
+      end
+
+      def update_child_nested_collection_relationship_indices
+        children = find_children_of(destroyed_id: id)
+        # puts children.to_s
+        children.each do |child|
+          # puts child.id.to_s
+          reindex_nested_relationships_for(id: child.id, extent: Hyrax::Adapters::NestingIndexAdapter::LIMITED_REINDEX)
+        end
+      end
+    end
+
+    def update_index(*args)
+      _run_update_index_callbacks { super }
+    end
+
+    def find_children_of(destroyed_id:)
+      ActiveFedora::SolrService.query(ActiveFedora::SolrQueryBuilder.construct_query(member_of_collection_ids_ssim: destroyed_id), rows: 500_000)
+    end
+
+    # Only models which include Hyrax::CollectionNesting will respond to this method.
+    # Used to determine whether a model gets reindexed via Samvera::NestingIndexer during full repository reindexing,
+    def use_nested_reindexing?
+      true
+    end
+
+    # The following methods allow an option to reindex an object only if the nesting indexer fields are not
+    # already in the object's solr document. Added to prevent unnecessary indexing of all ancestors of a parent
+    # when one child gets added to the parent. By default, we do the full graph indexing.
+    def reindex_extent
+      @reindex_extent ||= Hyrax::Adapters::NestingIndexAdapter::LIMITED_REINDEX
+    end
+
+    def reindex_extent=(val)
+      @reindex_extent = val
+    end
+
+    private
+
+    def reindex_nested_relationships_for(id:, extent:)
+      Hyrax.config.nested_relationship_reindexer.call(id: id, extent: extent)
+    end
+  end
+end