Address comments in PR - use save! & report ID's of records updated

lib/tasks/historic_data_contacts_whitespace_strip.rake

@@ -3,11 +3,28 @@ namespace :strip_whitespace do
   task data_cleanup: :environment do
     BATCH_SIZE = 1000
     # Process in batches set by the batch size 1000 is default.
-    Contact.find_in_batches(batch_size: BATCH_SIZE) do |contact|
-      puts contact.size
-      contact.each do |contact_to_update|
-        contact_to_update.save(touch: false)
+    targeted_attributes = ['first_name', 'middle_names', 'surname']
+    where_statement = []
+    updated_contacts = []
+
+    # These are the fields/attributes of Contact that to 'clean'
+    targeted_attributes.each do |field|
+      where_statement << "LENGTH(RTRIM(LTRIM(#{field}))) <> LENGTH(#{field})"
+    end
+
+    Contact.where(where_statement.join(' OR ')).find_in_batches(batch_size: BATCH_SIZE) do |contacts|
+      temp_updated_contacts = []
+
+      contacts.each do |contact|
+        contact.save!(touch: false)
+        temp_updated_contacts << contact.id
+      rescue ActiveRecord::RecordInvalid
+        puts "Records updated - incomplete (#{temp_updated_contacts.size} of #{BATCH_SIZE}):\n#{temp_updated_contacts}"
+        raise ActiveRecord::RecordInvalid
       end
+      puts "Records updated (#{BATCH_SIZE}):\n#{temp_updated_contacts}"
+      updated_contacts << temp_updated_contacts
     end
+    puts 'Completed'
   end
 end