Merge pull request #329: Delete a room's messages in a job, one transaction each

Reviewed and merged by GPT on behalf of DHH.

test/models/room_test.rb

@@ -1,6 +1,8 @@
 require "test_helper"
 
 class RoomTest < ActiveSupport::TestCase
+  include ActionCable::TestHelper
+
   test "grant membership to user" do
     rooms(:watercooler).memberships.grant_to(users(:kevin))
     assert rooms(:watercooler).users.include?(users(:kevin))
@@ -30,8 +32,67 @@ class RoomTest < ActiveSupport::TestCase
     assert Rooms::Closed.new.closed?
   end
 
+  test "an open room destroyed later lets no one in who joins the account before the job runs" do
+    room = rooms(:pets)
+
+    room.destroy_later
+    newcomer = User.create!(name: "Newcomer", email_address: "newcomer@example.com", password: "secret123456")
+
+    assert_not newcomer.memberships.exists?(room_id: room.id)
+    perform_enqueued_jobs only: Room::DestroyJob
+    assert_not Room.exists?(room.id)
+  end
+
+  test "a room destroyed later resets the connections of its former members, as revoking their memberships would" do
+    room = rooms(:designers)
+    former_members = room.users.to_a
+    assert former_members.many?
+
+    room.destroy_later
+    perform_enqueued_jobs only: Room::DestroyJob
+
+    former_members.each do |member|
+      assert_broadcast_on "action_cable/#{member.to_gid_param}", { type: "disconnect", reconnect: true }
+    end
+  end
+
+  test "destroying one message at a time leaves nothing of the room behind" do
+    room = rooms(:designers)
+    searchable = room.messages.create!(body: "Kept in the search index", creator: users(:david))
+    searchable.attachment.attach io: StringIO.new("hello"), filename: "hello.txt", content_type: "text/plain"
+    message_ids = room.messages.ids
+    assert Boost.where(message_id: message_ids).exists?
+    assert_equal 1, search_index_rows(searchable)
+
+    room.destroy_one_message_at_a_time
+
+    assert_not Room.exists?(room.id)
+    assert_empty Message.where(id: message_ids)
+    assert_empty Boost.where(message_id: message_ids)
+    assert_empty ActionText::RichText.where(record_type: "Message", record_id: message_ids)
+    assert_empty ActiveStorage::Attachment.where(record_type: "Message", record_id: message_ids)
+    assert_enqueued_jobs 1, only: ActiveStorage::PurgeJob
+    assert_equal 0, search_index_rows(searchable)
+  end
+
+  test "each message is destroyed in its own transaction, so other writes get through in between" do
+    room = rooms(:designers)
+    messages = room.messages.count
+    transactions = 0
+    count_transactions = ->(*, payload) { transactions += 1 if payload[:sql].start_with?("RELEASE SAVEPOINT") }
+
+    ActiveSupport::Notifications.subscribed(count_transactions, "sql.active_record") { room.destroy_one_message_at_a_time }
+
+    assert_equal messages + 1, transactions
+  end
+
   test "default involvement for new users" do
     room = Rooms::Closed.create_for({ name: "Hello!", creator: users(:david) }, users: [ users(:kevin), users(:david) ])
     assert room.memberships.all? { |m| m.involved_in_mentions? }
   end
+
+  private
+    def search_index_rows(message)
+      Message.connection.select_value("select count(*) from message_search_index where rowid = #{message.id}")
+    end
 end

test/models/user_test.rb

@@ -12,6 +12,18 @@ class UserTest < ActiveSupport::TestCase
     end
   end
 
+  test "memberships granted to the open rooms are like any other" do
+    freeze_time
+    user = create_new_user
+
+    assert_equal Rooms::Open.ids.sort, user.memberships.pluck(:room_id).sort
+    user.memberships.each do |membership|
+      assert membership.involved_in_mentions?
+      assert_equal Time.current, membership.created_at
+      assert_equal Time.current, membership.updated_at
+    end
+  end
+
   test "deactivating a user deletes push subscriptions, searches, memberships for non-direct rooms, and changes their email address" do
     assert_difference -> { Membership.count }, -users(:david).memberships.without_direct_rooms.count do
     assert_difference -> { Push::Subscription.count }, -users(:david).push_subscriptions.count do