DEV: Add user_id and post_user_id to MovedPost records (#30130)

Follow-up from this commit - 9b8af0ea9f

Adds helpful data into MovedPost records for later lookup. ALSO fixes notifications for freeze_original to point to the newly created post, not the moved post.

app/models/moved_post.rb

@@ -6,6 +6,12 @@ class MovedPost < ActiveRecord::Base
 
   belongs_to :new_topic, class_name: "Topic", foreign_key: :new_topic_id
   belongs_to :new_post, class_name: "Post", foreign_key: :new_post_id
+
+  # The author of the moved post
+  belongs_to :posting_user, class_name: "User", foreign_key: :post_user_id
+
+  # The user who moved the post
+  belongs_to :user
 end
 
 # == Schema Information
@@ -23,11 +29,15 @@ end
 #  created_new_topic :boolean          default(FALSE), not null
 #  created_at        :datetime         not null
 #  updated_at        :datetime         not null
+#  old_topic_title   :string
+#  post_user_id      :integer
+#  user_id           :integer
 #
 # Indexes
 #
 #  index_moved_posts_on_new_post_id                    (new_post_id)
 #  index_moved_posts_on_new_topic_id                   (new_topic_id)
+#  index_moved_posts_on_new_topic_id_and_post_user_id  (new_topic_id,post_user_id)
 #  index_moved_posts_on_old_post_id                    (old_post_id)
 #  index_moved_posts_on_old_post_number                (old_post_number)
 #  index_moved_posts_on_old_topic_id                   (old_topic_id)

app/models/post_mover.rb

@@ -11,8 +11,12 @@ class PostMover
   # freeze_original: :boolean  - if true, the original topic will be frozen but not deleted and posts will be "copied" to topic
   def initialize(original_topic, user, post_ids, move_to_pm: false, options: {})
     @original_topic = original_topic
+    @original_topic_title = original_topic.title
     @user = user
     @post_ids = post_ids
+    # For now we store a copy of post_ids. If `freeze_original` is present, we will have new post_ids.
+    # When we create the new posts, we will pluck out post_ids out of this and replace with updated ids.
+    @post_ids_after_move = post_ids
     @move_to_pm = move_to_pm
     @options = options
   end
@@ -307,6 +311,11 @@ class PostMover
     moved_post.disable_rate_limits! if @options[:freeze_original]
     moved_post.save(validate: false)
 
+    if moved_post.id != post.id
+      @post_ids_after_move =
+        @post_ids_after_move.map { |post_id| post_id == post.id ? moved_post.id : post_id }
+    end
+
     DiscourseEvent.trigger(:post_moved, moved_post, original_topic.id)
 
     # Move any links from the post to the new topic
@@ -337,6 +346,7 @@ class PostMover
       old_topic_id: post.topic_id,
       old_post_id: post.id,
       old_post_number: post.post_number,
+      post_user_id: post.user_id,
       new_topic_id: destination_topic.id,
       new_post_number: new_post_number,
       new_topic_title: destination_topic.title,
@@ -347,10 +357,12 @@ class PostMover
     metadata[:new_post_id] = new_post.id
     metadata[:now] = Time.zone.now
     metadata[:created_new_topic] = @creating_new_topic
+    metadata[:old_topic_title] = @original_topic_title
+    metadata[:user_id] = @user.id
 
     DB.exec(<<~SQL, metadata)
-      INSERT INTO moved_posts(old_topic_id, old_post_id, old_post_number, new_topic_id, new_topic_title, new_post_id, new_post_number, created_new_topic, created_at, updated_at)
+      INSERT INTO moved_posts(old_topic_id, old_topic_title, old_post_id, old_post_number, post_user_id, user_id, new_topic_id, new_topic_title, new_post_id, new_post_number, created_new_topic, created_at, updated_at)
-      VALUES (:old_topic_id, :old_post_id, :old_post_number, :new_topic_id, :new_topic_title, :new_post_id, :new_post_number, :created_new_topic, :now, :now)
+      VALUES (:old_topic_id, :old_topic_title, :old_post_id, :old_post_number, :post_user_id, :user_id, :new_topic_id, :new_topic_title, :new_post_id, :new_post_number, :created_new_topic, :now, :now)
     SQL
   end
 
@@ -703,7 +715,7 @@ class PostMover
   def enqueue_jobs(topic)
     @post_creator.enqueue_jobs if @post_creator
 
-    Jobs.enqueue(:notify_moved_posts, post_ids: post_ids, moved_by_id: user.id)
+    Jobs.enqueue(:notify_moved_posts, post_ids: @post_ids_after_move, moved_by_id: user.id)
 
     Jobs.enqueue(:delete_inaccessible_notifications, topic_id: topic.id)
   end

db/migrate/20241205162117_add_columns_to_moved_posts.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+class AddColumnsToMovedPosts < ActiveRecord::Migration[7.2]
+  def change
+    add_column :moved_posts, :old_topic_title, :string
+    add_column :moved_posts, :post_user_id, :integer
+    add_column :moved_posts, :user_id, :integer
+
+    # Index for querying moved_posts for post author given a new topic ID
+    add_index :moved_posts, %i[new_topic_id post_user_id]
+  end
+end

spec/models/post_mover_spec.rb

@@ -314,8 +314,11 @@ RSpec.describe PostMover do
               MovedPost.exists?(
                 new_topic: new_topic,
                 new_post_id: p2.id,
-                old_topic: topic,
+                old_topic_id: topic.id,
+                old_topic_title: topic.title,
                 old_post_id: p2.id,
+                post_user_id: p2.user_id,
+                user_id: user.id,
                 created_new_topic: true,
               ),
             ).to eq(true)
@@ -323,8 +326,11 @@ RSpec.describe PostMover do
               MovedPost.exists?(
                 new_topic: new_topic,
                 new_post_id: p4.id,
-                old_topic: topic,
+                old_topic_id: topic.id,
+                old_topic_title: topic.title,
                 old_post_id: p4.id,
+                post_user_id: p4.user_id,
+                user_id: user.id,
                 created_new_topic: true,
               ),
             ).to eq(true)
@@ -695,8 +701,11 @@ RSpec.describe PostMover do
               MovedPost.exists?(
                 new_topic: destination_topic,
                 new_post_id: p2.id,
-                old_topic: topic,
+                old_topic_id: topic.id,
+                old_topic_title: topic.title,
                 old_post_id: p2.id,
+                post_user_id: p2.user_id,
+                user_id: user.id,
                 created_new_topic: false,
               ),
             ).to eq(true)
@@ -704,8 +713,11 @@ RSpec.describe PostMover do
               MovedPost.exists?(
                 new_topic: destination_topic,
                 new_post_id: p4.id,
-                old_topic: topic,
+                old_topic_id: topic.id,
+                old_topic_title: topic.title,
                 old_post_id: p4.id,
+                post_user_id: p4.user_id,
+                user_id: user.id,
                 created_new_topic: false,
               ),
             ).to eq(true)
@@ -2703,8 +2715,11 @@ RSpec.describe PostMover do
         expect(
           MovedPost.exists?(
             old_topic_id: original_topic.id,
-            new_topic_id: destination_topic.id,
+            old_topic_title: original_topic.title,
             old_post_id: first_post.id,
+            post_user_id: first_post.user_id,
+            user_id: Discourse.system_user.id,
+            new_topic_id: destination_topic.id,
           ),
         ).to eq(true)
       end
@@ -2805,6 +2820,29 @@ RSpec.describe PostMover do
         expect(pm.posts.map(&:raw)).to include(*moving_posts.map(&:raw))
       end
 
+      describe "moved_post notifications" do
+        before { Jobs.run_immediately! }
+
+        it "Generates notifications pointing to the newly created post and topic" do
+          PostMover.new(
+            original_topic,
+            Discourse.system_user,
+            [first_post.id],
+            options: {
+              freeze_original: true,
+            },
+          ).to_topic(destination_topic.id)
+
+          notification =
+            Notification.find_by(
+              post_number: destination_topic.posts.find_by(raw: "first_post").post_number,
+              topic_id: destination_topic.id,
+              notification_type: Notification.types[:moved_post],
+            )
+          expect(notification).to be_present
+        end
+      end
+
       context "with rate limit" do
         before do
           RateLimiter.enable