From 0b947b6aabcec59ed0160e525d0eaac98bbb3d33 Mon Sep 17 00:00:00 2001
From: Alan Guo Xiang Tan <gxtan1990@gmail.com>
Date: Tue, 7 May 2024 11:06:31 +0800
Subject: [PATCH] DEV: Improve code comment about when ignored columns can be
 removed (#26894)

Ignored columns can only be dropped when its associated post-deploy
migration has been promoted to a regular migration. This is so because
Discourse doesn't rely on a schema file system to setup a brand new
database and thus the column information will be loaded by the
application first before the post-deploy migration runs.
---
 app/models/category.rb         | 6 +++---
 app/models/directory_column.rb | 3 +--
 app/models/email_token.rb      | 3 +--
 app/models/embeddable_host.rb  | 3 +--
 app/models/group.rb            | 3 +--
 app/models/invite.rb           | 3 +--
 app/models/post.rb             | 4 ++--
 app/models/tag.rb              | 2 +-
 app/models/topic.rb            | 4 ++--
 app/models/topic_user.rb       | 2 +-
 app/models/user_api_key.rb     | 2 +-
 app/models/user_option.rb      | 3 +--
 app/models/user_profile.rb     | 3 +--
 app/models/user_stat.rb        | 3 +--
 lib/migration/safe_migrate.rb  | 2 +-
 15 files changed, 19 insertions(+), 27 deletions(-)

diff --git a/app/models/category.rb b/app/models/category.rb
index 907bc1e42e5..b2fa9d56e05 100644
--- a/app/models/category.rb
+++ b/app/models/category.rb
@@ -4,9 +4,9 @@ class Category < ActiveRecord::Base
   RESERVED_SLUGS = ["none"]
 
   self.ignored_columns = [
-    :suppress_from_latest, # TODO(2020-11-18): remove
-    :required_tag_group_id, # TODO(2023-04-01): remove
-    :min_tags_from_required_group, # TODO(2023-04-01): remove
+    :suppress_from_latest, # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
+    :required_tag_group_id, # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
+    :min_tags_from_required_group, # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   ]
 
   include Searchable
diff --git a/app/models/directory_column.rb b/app/models/directory_column.rb
index 73a0762a1e8..0722be0fd95 100644
--- a/app/models/directory_column.rb
+++ b/app/models/directory_column.rb
@@ -1,8 +1,7 @@
 # frozen_string_literal: true
 
 class DirectoryColumn < ActiveRecord::Base
-  # TODO(2021-06-18): Remove automatic column
-  self.ignored_columns = ["automatic"]
+  self.ignored_columns = ["automatic"] # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   self.inheritance_column = nil
 
   enum type: { automatic: 0, user_field: 1, plugin: 2 }, _scopes: false
diff --git a/app/models/email_token.rb b/app/models/email_token.rb
index 5cfcfc446d8..796db3affc0 100644
--- a/app/models/email_token.rb
+++ b/app/models/email_token.rb
@@ -40,8 +40,7 @@ class EmailToken < ActiveRecord::Base
     end
   end
 
-  # TODO(2022-01-01): Remove
-  self.ignored_columns = %w[token]
+  self.ignored_columns = %w[token] # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
 
   def self.scopes
     @scopes ||= Enum.new(signup: 1, password_reset: 2, email_login: 3, email_update: 4)
diff --git a/app/models/embeddable_host.rb b/app/models/embeddable_host.rb
index 285c6fd1b79..2b25be6e581 100644
--- a/app/models/embeddable_host.rb
+++ b/app/models/embeddable_host.rb
@@ -10,8 +10,7 @@ class EmbeddableHost < ActiveRecord::Base
     self.host.sub!(%r{/.*\z}, "")
   end
 
-  # TODO(2021-07-23): Remove
-  self.ignored_columns = ["path_whitelist"]
+  self.ignored_columns = ["path_whitelist"] # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
 
   def self.record_for_url(uri)
     if uri.is_a?(String)
diff --git a/app/models/group.rb b/app/models/group.rb
index 5e0928c11a5..3a7f2a4f5d9 100644
--- a/app/models/group.rb
+++ b/app/models/group.rb
@@ -3,8 +3,7 @@
 require "net/imap"
 
 class Group < ActiveRecord::Base
-  # TODO(2021-05-26): remove
-  self.ignored_columns = %w[flair_url]
+  self.ignored_columns = %w[flair_url] # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
 
   include HasCustomFields
   include AnonCacheInvalidator
diff --git a/app/models/invite.rb b/app/models/invite.rb
index 2aa7c91f6fd..43b75133583 100644
--- a/app/models/invite.rb
+++ b/app/models/invite.rb
@@ -13,8 +13,7 @@ class Invite < ActiveRecord::Base
   include RateLimiter::OnCreateRecord
   include Trashable
 
-  # TODO(2021-05-22): remove
-  self.ignored_columns = %w[user_id redeemed_at]
+  self.ignored_columns = %w[user_id redeemed_at] # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
 
   BULK_INVITE_EMAIL_LIMIT = 200
   DOMAIN_REGEX =
diff --git a/app/models/post.rb b/app/models/post.rb
index 0d103d15e73..52ee157a6df 100644
--- a/app/models/post.rb
+++ b/app/models/post.rb
@@ -11,8 +11,8 @@ class Post < ActiveRecord::Base
   include LimitedEdit
 
   self.ignored_columns = [
-    "avg_time", # TODO(2021-01-04): remove
-    "image_url", # TODO(2021-06-01): remove
+    "avg_time", # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
+    "image_url", # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   ]
 
   cattr_accessor :plugin_permitted_create_params, :plugin_permitted_update_params
diff --git a/app/models/tag.rb b/app/models/tag.rb
index b258cea67fd..7a935be68af 100644
--- a/app/models/tag.rb
+++ b/app/models/tag.rb
@@ -6,7 +6,7 @@ class Tag < ActiveRecord::Base
   include HasSanitizableFields
 
   self.ignored_columns = [
-    "topic_count", # TODO(tgxworld): Remove on 1 July 2023
+    "topic_count", # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   ]
 
   RESERVED_TAGS = [
diff --git a/app/models/topic.rb b/app/models/topic.rb
index 233a9aed103..c7d943e3033 100644
--- a/app/models/topic.rb
+++ b/app/models/topic.rb
@@ -16,8 +16,8 @@ class Topic < ActiveRecord::Base
   EXTERNAL_ID_MAX_LENGTH = 50
 
   self.ignored_columns = [
-    "avg_time", # TODO(2021-01-04): remove
-    "image_url", # TODO(2021-06-01): remove
+    "avg_time", # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
+    "image_url", # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   ]
 
   def_delegator :featured_users, :user_ids, :featured_user_ids
diff --git a/app/models/topic_user.rb b/app/models/topic_user.rb
index cc9ce74b5c5..9d35a5f8c7d 100644
--- a/app/models/topic_user.rb
+++ b/app/models/topic_user.rb
@@ -2,7 +2,7 @@
 
 class TopicUser < ActiveRecord::Base
   self.ignored_columns = [
-    :highest_seen_post_number, # Remove after 01 Jan 2022
+    :highest_seen_post_number, # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   ]
 
   belongs_to :user
diff --git a/app/models/user_api_key.rb b/app/models/user_api_key.rb
index 59815a5c70c..9d004cf3bd9 100644
--- a/app/models/user_api_key.rb
+++ b/app/models/user_api_key.rb
@@ -2,7 +2,7 @@
 
 class UserApiKey < ActiveRecord::Base
   self.ignored_columns = [
-    "scopes", # TODO(2020-12-18): remove
+    "scopes", # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   ]
 
   REVOKE_MATCHER = RouteMatcher.new(actions: "user_api_keys#revoke", methods: :post, params: [:id])
diff --git a/app/models/user_option.rb b/app/models/user_option.rb
index 18024366a12..0ee8e71472e 100644
--- a/app/models/user_option.rb
+++ b/app/models/user_option.rb
@@ -14,8 +14,7 @@ class UserOption < ActiveRecord::Base
   }
 
   self.ignored_columns = [
-    "disable_jump_reply", # Remove once 20210706091905 is promoted from post_deploy to regular migration
-    "sidebar_list_destination", # TODO(osama): Remove in January 2024
+    "sidebar_list_destination", # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
   ]
 
   self.primary_key = :user_id
diff --git a/app/models/user_profile.rb b/app/models/user_profile.rb
index 91920dd9d70..5ee6ce6e9d8 100644
--- a/app/models/user_profile.rb
+++ b/app/models/user_profile.rb
@@ -1,8 +1,7 @@
 # frozen_string_literal: true
 
 class UserProfile < ActiveRecord::Base
-  # TODO Remove `badge_granted_title` after 2023-09-01
-  self.ignored_columns = ["badge_granted_title"]
+  self.ignored_columns = ["badge_granted_title"] # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
 
   BAKED_VERSION = 1
 
diff --git a/app/models/user_stat.rb b/app/models/user_stat.rb
index 32e00681bd9..65f0f98aa9e 100644
--- a/app/models/user_stat.rb
+++ b/app/models/user_stat.rb
@@ -3,8 +3,7 @@ class UserStat < ActiveRecord::Base
   belongs_to :user
   after_save :trigger_badges
 
-  # TODO(2021-05-13): Remove
-  self.ignored_columns = ["topic_reply_count"]
+  self.ignored_columns = ["topic_reply_count"] # TODO: Remove when 20240212034010_drop_deprecated_columns has been promoted to pre-deploy
 
   def self.ensure_consistency!(last_seen = 1.hour.ago)
     reset_bounce_scores
diff --git a/lib/migration/safe_migrate.rb b/lib/migration/safe_migrate.rb
index def669ff037..7806a3044cb 100644
--- a/lib/migration/safe_migrate.rb
+++ b/lib/migration/safe_migrate.rb
@@ -141,7 +141,7 @@ class Migration::SafeMigrate
         or rename columns.
 
         Note, to minimize disruption use self.ignored_columns = ["column name"] on your
-        ActiveRecord model, this can be removed 6 months or so later.
+        ActiveRecord model, this can be removed after the post deployment migration has been promoted to a regular migration.
 
         This protection is in place to protect us against dropping columns that are currently
         in use by live applications.