Remove references to collection from members when collection.deleted …

…event is published

app/services/hyrax/listeners/member_cleanup_listener.rb

@@ -3,7 +3,7 @@
 module Hyrax
   module Listeners
     ##
-    # Listens for object deleted events and cleans up associated members
+    # Listens for resource deleted events and cleans up associated members
     class MemberCleanupListener
       # Called when 'object.deleted' event is published
       # @param [Dry::Events::Event] event
@@ -16,14 +16,34 @@ def on_object_deleted(event)
           begin
             Hyrax.persister.delete(resource: file_set)
             Hyrax.publisher
-                 .publish('object.deleted', object: file_set, id: file_set.id, user: user)
+                 .publish('object.deleted', object: file_set, id: file_set.id, user: event[:user])
           rescue StandardError # we don't uncaught errors looping filesets
             Hyrax.logger.warn "Failed to delete #{file_set.class}:#{file_set.id} " \
                               "during cleanup for resource: #{event[:object]}. " \
                               'This member may now be orphaned.'
           end
         end
       end
+
+      # Called when 'collection.deleted' event is published
+      # @param [Dry::Events::Event] event
+      # @return [void]
+      def on_collection_deleted(event)
+        return unless event.payload.key?(:collection) # legacy callback
+        return if event[:collection].is_a?(ActiveFedora::Base) # handled by legacy code
+
+        Hyrax.custom_queries.find_members_of(collection: event[:collection]).each do |resource|
+          begin
+            resource.member_of_collection_ids -= [event[:collection].id]
+            Hyrax.persister.save(resource: resource)
+            Hyrax.publisher
+                 .publish('collection.membership.updated', collection: event[:collection], user: event[:user])
+          rescue StandardError
+            Hyrax.logger.warn "Failed to remove collection reference from #{work.class}:#{work.id} " \
+                              "during cleanup for collection: #{event[:collection]}. "
+          end
+        end
+      end
     end
   end
 end

spec/services/hyrax/listeners/member_cleanup_listener_spec.rb

@@ -0,0 +1,58 @@
+# frozen_string_literal: true
+
+require 'hyrax/specs/spy_listener'
+
+RSpec.describe Hyrax::Listeners::MemberCleanupListener do
+  subject(:listener) { described_class.new }
+  let(:data)         { { collection: collection, user: user } }
+  let(:event)        { Dry::Events::Event.new(event_type, data) }
+  let(:user)         { FactoryBot.create(:user) }
+  let(:spy_listener) { Hyrax::Specs::SpyListener.new }
+
+  before { Hyrax.publisher.subscribe(spy_listener) }
+  after  { Hyrax.publisher.unsubscribe(spy_listener) }
+
+  describe '#on_object_deleted' do
+    let(:data)         { { object: work, user: user } }
+    let(:event_type)   { :on_object_deleted }
+    let(:work)         { FactoryBot.valkyrie_create(:hyrax_work, member_ids: [file_set.id]) }
+    let(:file_set)     { FactoryBot.valkyrie_create(:hyrax_file_set) }
+
+    it 'removes child file set objects' do
+      expect { listener.on_object_deleted(event) }
+        .to change { Hyrax.custom_queries.find_child_filesets(resource: event[:object]).size }
+        .from(1)
+        .to(0)
+    end
+
+    it 'publishes events' do
+      listener.on_object_deleted(event)
+      expect(spy_listener.object_deleted&.payload)
+        .to include(id: file_set.id, object: file_set, user: user)
+    end
+  end
+
+  describe '#on_collection_deleted' do
+    let(:collection)   { FactoryBot.valkyrie_create(:hyrax_collection) }
+    let(:data)         { { collection: collection, user: user } }
+    let(:event_type)   { :on_collection_deleted }
+    let(:work)         { FactoryBot.valkyrie_create(:monograph, member_of_collection_ids: [collection.id]) }
+
+    before do
+      work
+    end
+
+    it 'removes collection references from member objects' do
+      expect { listener.on_collection_deleted(event) }
+        .to change { Hyrax.custom_queries.find_members_of(collection: event[:collection]).size }
+        .from(1)
+        .to(0)
+    end
+
+    it 'publishes events' do
+      listener.on_collection_deleted(event)
+      expect(spy_listener.collection_membership_updated&.payload)
+        .to include(collection: collection, user: user)
+    end
+  end
+end