[MM-52541] Mark files as deleted along with thread (#23226)

* mark thread files as deleted

* add missing check

* improve query

* Stopped rendering post preview if post is deleted

* Fixed lint error

* Fixed test

* updated types

* Removed deleted post from other post's embed data

* Added tests

* Apply suggestions from code review

Co-authored-by: Daniel Espino García <larkox@gmail.com>

* lint fix

---------

Co-authored-by: Konstantinos Pittas <konstantinos.pittas@mattermost.com>
Co-authored-by: Harshil Sharma <harshilsharma63@gmail.com>
Co-authored-by: Mattermost Build <build@mattermost.com>
Co-authored-by: Harshil Sharma <18575143+harshilsharma63@users.noreply.github.com>
Co-authored-by: Daniel Espino García <larkox@gmail.com>

server/channels/store/sqlstore/post_store.go

@@ -2913,6 +2913,30 @@ func (s *SqlPostStore) deleteThread(transaction *sqlxTxWrapper, postId string, d
 		return errors.Wrapf(err, "failed to mark thread for root post %s as deleted", postId)
 	}
 
+	return s.deleteThreadFiles(transaction, postId, deleteAtTime)
+}
+
+func (s *SqlPostStore) deleteThreadFiles(transaction *sqlxTxWrapper, postID string, deleteAtTime int64) error {
+	var query sq.UpdateBuilder
+	if s.DriverName() == model.DatabaseDriverPostgres {
+		query = s.getQueryBuilder().Update("FileInfo").
+			Set("DeleteAt", deleteAtTime).
+			From("Posts")
+	} else {
+		query = s.getQueryBuilder().Update("FileInfo", "Posts").
+			Set("FileInfo.DeleteAt", deleteAtTime)
+	}
+
+	query = query.Where(sq.And{
+		sq.Expr("FileInfo.PostId = Posts.Id"),
+		sq.Eq{"Posts.RootId": postID},
+	})
+
+	_, err := transaction.ExecBuilder(query)
+	if err != nil {
+		return errors.Wrapf(err, "failed to mark files of thread post %s as deleted", postID)
+	}
+
 	return nil
 }
 

server/channels/store/storetest/post_store.go

@@ -1303,6 +1303,88 @@ func testPostStoreDelete(t *testing.T, ss store.Store) {
 		// last reply at should be 0
 		require.Equal(t, int64(0), thread.LastReplyAt)
 	})
+
+	t.Run("thread with file attachments", func(t *testing.T) {
+		teamId := model.NewId()
+		channel, err := ss.Channel().Save(&model.Channel{
+			TeamId:      teamId,
+			DisplayName: "DisplayName1",
+			Name:        "channel" + model.NewId(),
+			Type:        model.ChannelTypeOpen,
+		}, -1)
+		require.NoError(t, err)
+
+		// Create a root post
+		rootPost1, err := ss.Post().Save(&model.Post{
+			ChannelId: channel.Id,
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+		})
+		require.NoError(t, err)
+
+		// Create another root post
+		rootPost2, err := ss.Post().Save(&model.Post{
+			ChannelId: channel.Id,
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+		})
+		require.NoError(t, err)
+
+		// Reply to first root post with file attachments
+		replyPost1, err := ss.Post().Save(&model.Post{
+			ChannelId: rootPost1.ChannelId,
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+			RootId:    rootPost1.Id,
+		})
+		require.NoError(t, err)
+		file11, err := ss.FileInfo().Save(&model.FileInfo{
+			Id:        model.NewId(),
+			PostId:    replyPost1.Id,
+			CreatorId: replyPost1.UserId,
+			Path:      "file1.txt",
+		})
+		require.NoError(t, err)
+		file12, err := ss.FileInfo().Save(&model.FileInfo{
+			Id:        model.NewId(),
+			PostId:    replyPost1.Id,
+			CreatorId: replyPost1.UserId,
+			Path:      "file2.png",
+		})
+		require.NoError(t, err)
+
+		// Reply to second root post with file attachments
+		replyPost2, err := ss.Post().Save(&model.Post{
+			ChannelId: rootPost2.ChannelId,
+			UserId:    model.NewId(),
+			Message:   NewTestId(),
+			RootId:    rootPost2.Id,
+		})
+		require.NoError(t, err)
+		file21, err := ss.FileInfo().Save(&model.FileInfo{
+			Id:        model.NewId(),
+			PostId:    replyPost2.Id,
+			CreatorId: replyPost2.UserId,
+			Path:      "file1.txt",
+		})
+		require.NoError(t, err)
+
+		// Delete the first root post
+		err = ss.Post().Delete(rootPost1.Id, model.GetMillis(), "")
+		require.NoError(t, err)
+
+		// Verify the reply post's files are deleted
+		_, err = ss.FileInfo().Get(file11.Id)
+		require.Error(t, err, "Deleted id should have failed")
+		require.IsType(t, &store.ErrNotFound{}, err)
+		_, err = ss.FileInfo().Get(file12.Id)
+		require.Error(t, err, "Deleted id should have failed")
+		require.IsType(t, &store.ErrNotFound{}, err)
+
+		// Verify the other reply post's files are NOT deleted
+		_, err = ss.FileInfo().Get(file21.Id)
+		require.NoError(t, err, "Not deleted id should have succeeded")
+	})
 }
 
 func testPostStorePermDelete1Level(t *testing.T, ss store.Store) {