drop root_account_id from conversations tables

This removes the root_account_id from Conversation,
ConversationParticipant, ConversationMessage, and
ConversationMessageParticipant. We are opting to do something similar to
whats already being done in conversation with multiple root account ids
instead.

fixes VICE-549
flag=none

/ ---- ---- \
| Test Plan |
\ ---- ---- /

- Run the migration
  - bundle exec rake db:migrate:up VERSION=20200615170938
- Verify that the Conversation, ConversationParticipant,
  ConversationMessage, and ConversationMessageParticipant tables no
  longer have the `root_account_id` column

Change-Id: I7f736d96556ef86dc033aeb30bb37497809a0a29
Reviewed-on: https://gerrit.instructure.com/c/canvas-lms/+/240320
Tested-by: Service Cloud Jenkins <svc.cloudjenkins@instructure.com>
Reviewed-by: Rob Orton <rob@instructure.com>
QA-Review: Rob Orton <rob@instructure.com>
Product-Review: Rob Orton <rob@instructure.com>

app/models/conversation.rb

@@ -17,6 +17,8 @@
 #
 
 class Conversation < ActiveRecord::Base
+  self.ignored_columns = %i[root_account_id]
+
   include SimpleTags
   include ModelCache
   include SendToStream

app/models/conversation_message.rb

@@ -19,6 +19,8 @@
 require 'atom'
 
 class ConversationMessage < ActiveRecord::Base
+  self.ignored_columns = %i[root_account_id]
+
   include HtmlTextHelper
 
   include Rails.application.routes.url_helpers

app/models/conversation_message_participant.rb

@@ -17,6 +17,8 @@
 #
 
 class ConversationMessageParticipant < ActiveRecord::Base
+  self.ignored_columns = %i[root_account_id]
+
   include SimpleTags
   include Workflow
 

app/models/conversation_participant.rb

@@ -17,6 +17,8 @@
 #
 
 class ConversationParticipant < ActiveRecord::Base
+  self.ignored_columns = %i[root_account_id]
+
   include Workflow
   include TextHelper
   include SimpleTags

db/migrate/20200424200625_add_root_account_id_to_conversations.rb

@@ -1,31 +0,0 @@
-#
-# Copyright (C) 2020 - present Instructure, Inc.
-#
-# This file is part of Canvas.
-#
-# Canvas is free software: you can redistribute it and/or modify it under
-# the terms of the GNU Affero General Public License as published by the Free
-# Software Foundation, version 3 of the License.
-#
-# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
-# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
-# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
-# details.
-#
-# You should have received a copy of the GNU Affero General Public License along
-# with this program. If not, see <http://www.gnu.org/licenses/>.
-
-class AddRootAccountIdToConversations < ActiveRecord::Migration[5.2]
-  include MigrationHelpers::AddColumnAndFk
-
-  tag :predeploy
-  disable_ddl_transaction!
-
-  def up
-    add_column_and_fk :conversations, :root_account_id, :accounts, if_not_exists: true
-  end
-
-  def down
-    remove_column :conversations, :root_account_id
-  end
-end

db/migrate/20200424201444_add_root_account_id_to_conversation_participants.rb

@@ -1,31 +0,0 @@
-#
-# Copyright (C) 2020 - present Instructure, Inc.
-#
-# This file is part of Canvas.
-#
-# Canvas is free software: you can redistribute it and/or modify it under
-# the terms of the GNU Affero General Public License as published by the Free
-# Software Foundation, version 3 of the License.
-#
-# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
-# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
-# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
-# details.
-#
-# You should have received a copy of the GNU Affero General Public License along
-# with this program. If not, see <http://www.gnu.org/licenses/>.
-
-class AddRootAccountIdToConversationParticipants < ActiveRecord::Migration[5.2]
-  include MigrationHelpers::AddColumnAndFk
-
-  tag :predeploy
-  disable_ddl_transaction!
-
-  def up
-    add_column_and_fk :conversation_participants, :root_account_id, :accounts, if_not_exists: true
-  end
-
-  def down
-    remove_column :conversation_participants, :root_account_id
-  end
-end

db/migrate/20200511193351_add_root_account_id_to_conversation_messages.rb

@@ -1,31 +0,0 @@
-#
-# Copyright (C) 2020 - present Instructure, Inc.
-#
-# This file is part of Canvas.
-#
-# Canvas is free software: you can redistribute it and/or modify it under
-# the terms of the GNU Affero General Public License as published by the Free
-# Software Foundation, version 3 of the License.
-#
-# Canvas is distributed in the hope that it will be useful, but WITHOUT ANY
-# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
-# A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
-# details.
-#
-# You should have received a copy of the GNU Affero General Public License along
-# with this program. If not, see <http://www.gnu.org/licenses/>.
-#
-class AddRootAccountIdToConversationMessages < ActiveRecord::Migration[5.2]
-  include MigrationHelpers::AddColumnAndFk
-
-  tag :predeploy
-  disable_ddl_transaction!
-
-  def up
-    add_column_and_fk :conversation_messages, :root_account_id, :accounts, if_not_exists: true
-  end
-
-  def down
-    remove_column :conversation_messages, :root_account_id
-  end
-end

db/migrate/20200609161512_add_index_to_root_account_ids.rb

@@ -67,8 +67,6 @@ class AddIndexToRootAccountIds < ActiveRecord::Migration[5.2]
     add_index :custom_gradebook_columns, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :learning_outcome_groups, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :custom_gradebook_column_data, :root_account_id, algorithm: :concurrently, if_not_exists: true
-    add_index :conversations, :root_account_id, algorithm: :concurrently, if_not_exists: true
-    add_index :conversation_participants, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :master_courses_master_migrations, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :learning_outcomes, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :learning_outcome_question_results, :root_account_id, algorithm: :concurrently, if_not_exists: true
@@ -89,8 +87,6 @@ class AddIndexToRootAccountIds < ActiveRecord::Migration[5.2]
     add_index :calendar_events, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :folders, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :communication_channels, :root_account_id, algorithm: :concurrently, if_not_exists: true
-    add_index :conversation_messages, :root_account_id, algorithm: :concurrently, if_not_exists: true
-    add_index :conversation_message_participants, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :favorites, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :discussion_topics, :root_account_id, algorithm: :concurrently, if_not_exists: true
     add_index :discussion_entry_participants, :root_account_id, algorithm: :concurrently, if_not_exists: true

db/migrate/20200615170938_drop_root_account_id_from_conversations_tables.rb

@@ -14,18 +14,14 @@
 #
 # You should have received a copy of the GNU Affero General Public License along
 # with this program. If not, see <http://www.gnu.org/licenses/>.
-#
-class AddRootAccountIdToConversationMessageParticipants < ActiveRecord::Migration[5.2]
-  include MigrationHelpers::AddColumnAndFk
 
-  tag :predeploy
+class DropRootAccountIdFromConversationsTables < ActiveRecord::Migration[5.2]
-  disable_ddl_transaction!
+  tag :postdeploy
 
-  def up
+  def change
-    add_column_and_fk :conversation_message_participants, :root_account_id, :accounts, if_not_exists: true
+    remove_column :conversations, :root_account_id if column_exists?(:conversations, :root_account_id)
-  end
+    remove_column :conversation_participants, :root_account_id if column_exists?(:conversation_participants, :root_account_id)
-
+    remove_column :conversation_messages, :root_account_id if column_exists?(:conversation_messages, :root_account_id)
-  def down
+    remove_column :conversation_message_participants, :root_account_id if column_exists?(:conversation_message_participants, :root_account_id)
-    remove_column :conversation_message_participants, :root_account_id
   end
 end