feat(CommunitiesManager): introduce `CreateHistoryArchiveTorrentFromMessages` API

Prior to this commit we had a `CreateHistoryArchiveTorrent()` API which
takes a `startDate`, an `endDate` and a `partition` to create a bunch of
message archives, given a certain time range.

The function expects the messages to live in the database, which means,
all messages that need to be archived have to be saved there at some
point.

This turns out to be an issue when importing communities from third
party services, where, sometimes, there are several thousands of messages
including attachment payloads, that have to be save to the database
first.

There are only two options to get the messages into the database:

1. Make one write operation with all messages - this slow, takes a long
   time and blocks the database until done
2. Create message chunks and perform multiple write operations - this is
   also slow, takes long but makes the database a bit more responsive as
   it's many smaller operations instead of one big one

Option 2) turned out to not be super feasible either as sometimes,
inserting even a single such message can take up to 10 seconds
(depending on payload)

Which brings me to the third option.

**A third option** is to not store those imported messages as waku
message into the database, just to later query them again to create the
archives, but instead create the archives right away from all the
messages that have been loaded into memory.

This is significantly faster and doesn't block the database.

To make this possible, this commit introduces
a `CreateHistoryArchiveTorrentFromMessages()` API, and
a `CreateHistoryArchiveTorrentFromDB()` API which can be used for
different use cases.

protocol/communities/manager.go

@@ -1538,7 +1538,7 @@ func (m *Manager) GetHistoryArchivePartitionStartTimestamp(communityID types.Hex
 
 func (m *Manager) CreateAndSeedHistoryArchive(communityID types.HexBytes, topics []types.TopicType, startDate time.Time, endDate time.Time, partition time.Duration, encrypt bool) error {
 	m.UnseedHistoryArchiveTorrent(communityID)
-	_, err := m.CreateHistoryArchiveTorrent(communityID, topics, startDate, endDate, partition, encrypt)
+	_, err := m.CreateHistoryArchiveTorrentFromDB(communityID, topics, startDate, endDate, partition, encrypt)
 	if err != nil {
 		return err
 	}
@@ -1626,7 +1626,17 @@ type EncodedArchiveData struct {
 	bytes   []byte
 }
 
-func (m *Manager) CreateHistoryArchiveTorrent(communityID types.HexBytes, topics []types.TopicType, startDate time.Time, endDate time.Time, partition time.Duration, encrypt bool) ([]string, error) {
+func (m *Manager) CreateHistoryArchiveTorrentFromMessages(communityID types.HexBytes, messages []*types.Message, topics []types.TopicType, startDate time.Time, endDate time.Time, partition time.Duration, encrypt bool) ([]string, error) {
+	return m.CreateHistoryArchiveTorrent(communityID, messages, topics, startDate, endDate, partition, encrypt)
+}
+
+func (m *Manager) CreateHistoryArchiveTorrentFromDB(communityID types.HexBytes, topics []types.TopicType, startDate time.Time, endDate time.Time, partition time.Duration, encrypt bool) ([]string, error) {
+
+	return m.CreateHistoryArchiveTorrent(communityID, make([]*types.Message, 0), topics, startDate, endDate, partition, encrypt)
+}
+func (m *Manager) CreateHistoryArchiveTorrent(communityID types.HexBytes, msgs []*types.Message, topics []types.TopicType, startDate time.Time, endDate time.Time, partition time.Duration, encrypt bool) ([]string, error) {
+
+	loadFromDB := len(msgs) == 0
 
 	from := startDate
 	to := from.Add(partition)
@@ -1692,9 +1702,19 @@ func (m *Manager) CreateHistoryArchiveTorrent(communityID types.HexBytes, topics
 			zap.Any("to", to),
 		)
 
-		messages, err := m.persistence.GetWakuMessagesByFilterTopic(topics, uint64(from.Unix()), uint64(to.Unix()))
+		var messages []types.Message
-		if err != nil {
+		if loadFromDB {
-			return archiveIDs, err
+			messages, err = m.persistence.GetWakuMessagesByFilterTopic(topics, uint64(from.Unix()), uint64(to.Unix()))
+			if err != nil {
+				return archiveIDs, err
+			}
+		} else {
+			for _, msg := range msgs {
+				if int64(msg.Timestamp) >= from.Unix() && int64(msg.Timestamp) < to.Unix() {
+					messages = append(messages, *msg)
+				}
+			}
+
 		}
 
 		if len(messages) == 0 {

protocol/communities/manager_test.go

@@ -275,7 +275,7 @@ func (s *ManagerSuite) TestCreateHistoryArchiveTorrent_WithoutMessages() {
 	// Partition of 7 days
 	partition := 7 * 24 * time.Hour
 
-	_, err = s.manager.CreateHistoryArchiveTorrent(community.ID(), topics, startDate, endDate, partition, false)
+	_, err = s.manager.CreateHistoryArchiveTorrentFromDB(community.ID(), topics, startDate, endDate, partition, false)
 	s.Require().NoError(err)
 
 	// There are no waku messages in the database so we don't expect
@@ -317,7 +317,7 @@ func (s *ManagerSuite) TestCreateHistoryArchiveTorrent_ShouldCreateArchive() {
 	err = s.manager.StoreWakuMessage(&message3)
 	s.Require().NoError(err)
 
-	_, err = s.manager.CreateHistoryArchiveTorrent(community.ID(), topics, startDate, endDate, partition, false)
+	_, err = s.manager.CreateHistoryArchiveTorrentFromDB(community.ID(), topics, startDate, endDate, partition, false)
 	s.Require().NoError(err)
 
 	_, err = os.Stat(s.manager.archiveDataFile(community.IDString()))
@@ -378,7 +378,7 @@ func (s *ManagerSuite) TestCreateHistoryArchiveTorrent_ShouldCreateMultipleArchi
 	err = s.manager.StoreWakuMessage(&message4)
 	s.Require().NoError(err)
 
-	_, err = s.manager.CreateHistoryArchiveTorrent(community.ID(), topics, startDate, endDate, partition, false)
+	_, err = s.manager.CreateHistoryArchiveTorrentFromDB(community.ID(), topics, startDate, endDate, partition, false)
 	s.Require().NoError(err)
 
 	index, err := s.manager.LoadHistoryArchiveIndexFromFile(s.manager.identity, community.ID())
@@ -427,7 +427,7 @@ func (s *ManagerSuite) TestCreateHistoryArchiveTorrent_ShouldAppendArchives() {
 	err = s.manager.StoreWakuMessage(&message1)
 	s.Require().NoError(err)
 
-	_, err = s.manager.CreateHistoryArchiveTorrent(community.ID(), topics, startDate, endDate, partition, false)
+	_, err = s.manager.CreateHistoryArchiveTorrentFromDB(community.ID(), topics, startDate, endDate, partition, false)
 	s.Require().NoError(err)
 
 	index, err := s.manager.LoadHistoryArchiveIndexFromFile(s.manager.identity, community.ID())
@@ -442,7 +442,149 @@ func (s *ManagerSuite) TestCreateHistoryArchiveTorrent_ShouldAppendArchives() {
 	err = s.manager.StoreWakuMessage(&message2)
 	s.Require().NoError(err)
 
-	_, err = s.manager.CreateHistoryArchiveTorrent(community.ID(), topics, startDate, endDate, partition, false)
+	_, err = s.manager.CreateHistoryArchiveTorrentFromDB(community.ID(), topics, startDate, endDate, partition, false)
+	s.Require().NoError(err)
+
+	index, err = s.manager.LoadHistoryArchiveIndexFromFile(s.manager.identity, community.ID())
+	s.Require().NoError(err)
+	s.Require().Len(index.Archives, 2)
+}
+
+func (s *ManagerSuite) TestCreateHistoryArchiveTorrentFromMessages() {
+	torrentConfig := buildTorrentConfig()
+	s.manager.SetTorrentConfig(&torrentConfig)
+
+	community, chatID, err := s.buildCommunityWithChat()
+	s.Require().NoError(err)
+
+	topic := types.BytesToTopic(transport.ToTopic(chatID))
+	topics := []types.TopicType{topic}
+
+	// Time range of 7 days
+	startDate := time.Date(2020, 1, 1, 00, 00, 00, 0, time.UTC)
+	endDate := time.Date(2020, 1, 7, 00, 00, 00, 0, time.UTC)
+	// Partition of 7 days, this should create a single archive
+	partition := 7 * 24 * time.Hour
+
+	message1 := buildMessage(startDate.Add(1*time.Hour), topic, []byte{1})
+	message2 := buildMessage(startDate.Add(2*time.Hour), topic, []byte{2})
+	// This message is outside of the startDate-endDate range and should not
+	// be part of the archive
+	message3 := buildMessage(endDate.Add(2*time.Hour), topic, []byte{3})
+
+	_, err = s.manager.CreateHistoryArchiveTorrentFromMessages(community.ID(), []*types.Message{&message1, &message2, &message3}, topics, startDate, endDate, partition, false)
+	s.Require().NoError(err)
+
+	_, err = os.Stat(s.manager.archiveDataFile(community.IDString()))
+	s.Require().NoError(err)
+	_, err = os.Stat(s.manager.archiveIndexFile(community.IDString()))
+	s.Require().NoError(err)
+	_, err = os.Stat(s.manager.torrentFile(community.IDString()))
+	s.Require().NoError(err)
+
+	index, err := s.manager.LoadHistoryArchiveIndexFromFile(s.manager.identity, community.ID())
+	s.Require().NoError(err)
+	s.Require().Len(index.Archives, 1)
+
+	totalData, err := os.ReadFile(s.manager.archiveDataFile(community.IDString()))
+	s.Require().NoError(err)
+
+	for _, metadata := range index.Archives {
+		archive := &protobuf.WakuMessageArchive{}
+		data := totalData[metadata.Offset : metadata.Offset+metadata.Size-metadata.Padding]
+
+		err = proto.Unmarshal(data, archive)
+		s.Require().NoError(err)
+
+		s.Require().Len(archive.Messages, 2)
+	}
+}
+
+func (s *ManagerSuite) TestCreateHistoryArchiveTorrentFromMessages_ShouldCreateMultipleArchives() {
+	torrentConfig := buildTorrentConfig()
+	s.manager.SetTorrentConfig(&torrentConfig)
+
+	community, chatID, err := s.buildCommunityWithChat()
+	s.Require().NoError(err)
+
+	topic := types.BytesToTopic(transport.ToTopic(chatID))
+	topics := []types.TopicType{topic}
+
+	// Time range of 3 weeks
+	startDate := time.Date(2020, 1, 1, 00, 00, 00, 0, time.UTC)
+	endDate := time.Date(2020, 1, 21, 00, 00, 00, 0, time.UTC)
+	// 7 days partition, this should create three archives
+	partition := 7 * 24 * time.Hour
+
+	message1 := buildMessage(startDate.Add(1*time.Hour), topic, []byte{1})
+	message2 := buildMessage(startDate.Add(2*time.Hour), topic, []byte{2})
+	// We expect 2 archives to be created for startDate - endDate of each
+	// 7 days of data. This message should end up in the second archive
+	message3 := buildMessage(startDate.Add(8*24*time.Hour), topic, []byte{3})
+	// This one should end up in the third archive
+	message4 := buildMessage(startDate.Add(14*24*time.Hour), topic, []byte{4})
+
+	_, err = s.manager.CreateHistoryArchiveTorrentFromMessages(community.ID(), []*types.Message{&message1, &message2, &message3, &message4}, topics, startDate, endDate, partition, false)
+	s.Require().NoError(err)
+
+	index, err := s.manager.LoadHistoryArchiveIndexFromFile(s.manager.identity, community.ID())
+	s.Require().NoError(err)
+	s.Require().Len(index.Archives, 3)
+
+	totalData, err := os.ReadFile(s.manager.archiveDataFile(community.IDString()))
+	s.Require().NoError(err)
+
+	// First archive has 2 messages
+	// Second archive has 1 message
+	// Third archive has 1 message
+	fromMap := map[uint64]int{
+		uint64(startDate.Unix()):                    2,
+		uint64(startDate.Add(partition).Unix()):     1,
+		uint64(startDate.Add(partition * 2).Unix()): 1,
+	}
+
+	for _, metadata := range index.Archives {
+		archive := &protobuf.WakuMessageArchive{}
+		data := totalData[metadata.Offset : metadata.Offset+metadata.Size-metadata.Padding]
+
+		err = proto.Unmarshal(data, archive)
+		s.Require().NoError(err)
+		s.Require().Len(archive.Messages, fromMap[metadata.Metadata.From])
+	}
+}
+
+func (s *ManagerSuite) TestCreateHistoryArchiveTorrentFromMessages_ShouldAppendArchives() {
+	torrentConfig := buildTorrentConfig()
+	s.manager.SetTorrentConfig(&torrentConfig)
+
+	community, chatID, err := s.buildCommunityWithChat()
+	s.Require().NoError(err)
+
+	topic := types.BytesToTopic(transport.ToTopic(chatID))
+	topics := []types.TopicType{topic}
+
+	// Time range of 1 week
+	startDate := time.Date(2020, 1, 1, 00, 00, 00, 0, time.UTC)
+	endDate := time.Date(2020, 1, 7, 00, 00, 00, 0, time.UTC)
+	// 7 days partition, this should create one archive
+	partition := 7 * 24 * time.Hour
+
+	message1 := buildMessage(startDate.Add(1*time.Hour), topic, []byte{1})
+
+	_, err = s.manager.CreateHistoryArchiveTorrentFromMessages(community.ID(), []*types.Message{&message1}, topics, startDate, endDate, partition, false)
+	s.Require().NoError(err)
+
+	index, err := s.manager.LoadHistoryArchiveIndexFromFile(s.manager.identity, community.ID())
+	s.Require().NoError(err)
+	s.Require().Len(index.Archives, 1)
+
+	// Time range of next week
+	startDate = time.Date(2020, 1, 7, 00, 00, 00, 0, time.UTC)
+	endDate = time.Date(2020, 1, 14, 00, 00, 00, 0, time.UTC)
+
+	message2 := buildMessage(startDate.Add(2*time.Hour), topic, []byte{2})
+
+	_, err = s.manager.CreateHistoryArchiveTorrentFromMessages(community.ID(), []*types.Message{&message2}, topics, startDate, endDate, partition, false)
 	s.Require().NoError(err)
 
 	index, err = s.manager.LoadHistoryArchiveIndexFromFile(s.manager.identity, community.ID())
@@ -472,7 +614,7 @@ func (s *ManagerSuite) TestSeedHistoryArchiveTorrent() {
 	err = s.manager.StoreWakuMessage(&message1)
 	s.Require().NoError(err)
 
-	_, err = s.manager.CreateHistoryArchiveTorrent(community.ID(), topics, startDate, endDate, partition, false)
+	_, err = s.manager.CreateHistoryArchiveTorrentFromDB(community.ID(), topics, startDate, endDate, partition, false)
 	s.Require().NoError(err)
 
 	err = s.manager.SeedHistoryArchiveTorrent(community.ID())
@@ -509,7 +651,7 @@ func (s *ManagerSuite) TestUnseedHistoryArchiveTorrent() {
 	err = s.manager.StoreWakuMessage(&message1)
 	s.Require().NoError(err)
 
-	_, err = s.manager.CreateHistoryArchiveTorrent(community.ID(), topics, startDate, endDate, partition, false)
+	_, err = s.manager.CreateHistoryArchiveTorrentFromDB(community.ID(), topics, startDate, endDate, partition, false)
 	s.Require().NoError(err)
 
 	err = s.manager.SeedHistoryArchiveTorrent(community.ID())