Method Add

pkg/rtc/migrationdatacache.go:36–55

Add adds a message to the cache if there is a gap between the last sequence number and cached messages then return the cache State: - MigrationDataCacheStateWaiting: waiting for the next packet (lastSeq + 1) of last sequence from old node - MigrationDataCacheStateTimeout: the next packet is not rece

(pkt *livekit.DataPacket)

//     continue to process the reliable messages, subscribers will see the gap after the publisher migration
//   - MigrationDataCacheStateDone: the next packet is received, participant can continue to process the reliable messages
func (c *MigrationDataCache) Add(pkt *livekit.DataPacket) MigrationDataCacheState {
	if c.state == MigrationDataCacheStateDone || c.state == MigrationDataCacheStateTimeout {
		return c.state
	}

	if pkt.Sequence <= c.lastSeq {
		return c.state
	}

	if pkt.Sequence == c.lastSeq+1 {
		c.state = MigrationDataCacheStateDone
		return c.state
	}

	c.pkts = append(c.pkts, pkt)
	if time.Now().After(c.expiredAt) {
		c.state = MigrationDataCacheStateTimeout
	}
	return c.state
}

func (c *MigrationDataCache) Get() []*livekit.DataPacket {
	return c.pkts