Delete the list node and indirect container proxy when you purge a fi…

…leset (#1368)

* delete the list node and indirect container proxy when you purge a fileset

Our current application isn't cleaning up all the proxies when you purge
a fileset.  This results in an `owning_class` error when trying to
perform a FileAttachementJob. `unlocked_obj.ordered_members.to_a` is `[nil]`

Hydra-works is confusing.  I can see why this might have been missed the
first time around

* fix the moving target bug

The problem with iterating through the proxies and trying to delete the
nil proxies in place is that on any subsequent deletes the index has moved.

For example
uo.ordered_members = [nil, nil]
uo.ordered_member_proxies.delete_at(0)
uo.ordered_members = [nil]
uo.ordered_member_proxies.delete_at(1)
uo.ordered_members = [nil]
etc...

CHANGELOG.md

@@ -6,6 +6,9 @@ and releases in Jupiter project adheres to [Semantic Versioning](http://semver.o
 
 ## [Unreleased]
 
+### Fixed
+- delete the list node and indirect container proxy when you purge a fileset [#1354](https://github.com/ualbertalib/jupiter/issues/1354)
+
 ## [1.2.18] - 2019-10-22
 - Removed Rack Attack
 

app/models/concerns/item_properties.rb

@@ -206,10 +206,14 @@ def add_communities_and_collections(communities, collections)
 
       def purge_filesets
         FileSet.where(item: id).each do |fs|
-          fs.unlock_and_fetch_ldp_object(&:delete)
+          fs.unlock_and_fetch_ldp_object do |fileset|
+            ordered_members.delete(fs) # delete the list node
+            members.delete(fs) # delete the indirect container proxy
+            fileset.delete # delete the fileset
+          end
         end
 
-        self.ordered_members = []
+        save
       end
 
       def push_item_id_for_preservation

lib/tasks/jupiter.rake

@@ -29,6 +29,27 @@ namespace :jupiter do
     puts 'Reindex completed!'
   end
 
+  desc 'cleanup orphaned proxies'
+  task cleanup_proxies: :environment do
+    puts 'Visiting all Items and Theses...'
+    (Item.all + Thesis.all).each do |item|
+      item.unlock_and_fetch_ldp_object do |uo|
+        changed = false
+        indexes = []
+        uo.ordered_member_proxies.each_with_index do |proxy, index|
+          next if proxy.proxy_for
+
+          indexes << index
+          puts "#{item.id} has a nil proxy"
+          changed = true
+        end
+        indexes.sort { |a, b| b <=> a }.each { |index| uo.ordered_member_proxies.delete_at(index) }
+        uo.save! if changed
+      end
+    end
+    puts 'Nil proxy search completed!'
+  end
+
   desc 'queue all items and theses in the system for preservation'
   task preserve_all_items_and_theses: :environment do
     puts 'Adding all Items and Theses to preservation queue...'