package transport import ( "context" "errors" "sync" "go.uber.org/zap" "github.com/status-im/status-go/eth-node/types" ) // EnvelopeState in local tracker type EnvelopeState int const ( // NotRegistered returned if asked hash wasn't registered in the tracker. NotRegistered EnvelopeState = -1 // EnvelopePosted is set when envelope was added to a local waku queue. EnvelopePosted EnvelopeState = iota + 1 // EnvelopeSent is set when envelope is sent to at least one peer. EnvelopeSent ) type EnvelopesMonitorConfig struct { EnvelopeEventsHandler EnvelopeEventsHandler MaxAttempts int MailserverConfirmationsEnabled bool IsMailserver func(types.EnodeID) bool Logger *zap.Logger } // EnvelopeEventsHandler used for two different event types. type EnvelopeEventsHandler interface { EnvelopeSent([][]byte) EnvelopeExpired([][]byte, error) MailServerRequestCompleted(types.Hash, types.Hash, []byte, error) MailServerRequestExpired(types.Hash) } // NewEnvelopesMonitor returns a pointer to an instance of the EnvelopesMonitor. func NewEnvelopesMonitor(w types.Waku, config EnvelopesMonitorConfig) *EnvelopesMonitor { logger := config.Logger if logger == nil { logger = zap.NewNop() } var api types.PublicWakuAPI if w != nil { api = w.PublicWakuAPI() } return &EnvelopesMonitor{ w: w, api: api, handler: config.EnvelopeEventsHandler, mailServerConfirmation: config.MailserverConfirmationsEnabled, maxAttempts: config.MaxAttempts, isMailserver: config.IsMailserver, logger: logger.With(zap.Namespace("EnvelopesMonitor")), // key is envelope hash (event.Hash) envelopes: map[types.Hash]EnvelopeState{}, messages: map[types.Hash]*types.NewMessage{}, attempts: map[types.Hash]int{}, identifiers: make(map[types.Hash][][]byte), // key is hash of the batch (event.Batch) batches: map[types.Hash]map[types.Hash]struct{}{}, } } // EnvelopesMonitor is responsible for monitoring waku envelopes state. type EnvelopesMonitor struct { w types.Waku api types.PublicWakuAPI handler EnvelopeEventsHandler mailServerConfirmation bool maxAttempts int mu sync.Mutex envelopes map[types.Hash]EnvelopeState batches map[types.Hash]map[types.Hash]struct{} messages map[types.Hash]*types.NewMessage attempts map[types.Hash]int identifiers map[types.Hash][][]byte wg sync.WaitGroup quit chan struct{} isMailserver func(peer types.EnodeID) bool logger *zap.Logger } // Start processing events. func (m *EnvelopesMonitor) Start() { m.quit = make(chan struct{}) m.wg.Add(1) go func() { m.handleEnvelopeEvents() m.wg.Done() }() } // Stop process events. func (m *EnvelopesMonitor) Stop() { close(m.quit) m.wg.Wait() } // Add hash to a tracker. func (m *EnvelopesMonitor) Add(identifiers [][]byte, envelopeHash types.Hash, message types.NewMessage) { m.mu.Lock() defer m.mu.Unlock() m.envelopes[envelopeHash] = EnvelopePosted m.identifiers[envelopeHash] = identifiers m.messages[envelopeHash] = &message m.attempts[envelopeHash] = 1 } func (m *EnvelopesMonitor) GetState(hash types.Hash) EnvelopeState { m.mu.Lock() defer m.mu.Unlock() state, exist := m.envelopes[hash] if !exist { return NotRegistered } return state } // handleEnvelopeEvents processes waku envelope events func (m *EnvelopesMonitor) handleEnvelopeEvents() { events := make(chan types.EnvelopeEvent, 100) // must be buffered to prevent blocking waku sub := m.w.SubscribeEnvelopeEvents(events) defer func() { close(events) sub.Unsubscribe() }() for { select { case <-m.quit: return case event := <-events: m.handleEvent(event) } } } // handleEvent based on type of the event either triggers // confirmation handler or removes hash from tracker func (m *EnvelopesMonitor) handleEvent(event types.EnvelopeEvent) { handlers := map[types.EventType]func(types.EnvelopeEvent){ types.EventEnvelopeSent: m.handleEventEnvelopeSent, types.EventEnvelopeExpired: m.handleEventEnvelopeExpired, types.EventBatchAcknowledged: m.handleAcknowledgedBatch, types.EventEnvelopeReceived: m.handleEventEnvelopeReceived, } if handler, ok := handlers[event.Event]; ok { handler(event) } } func (m *EnvelopesMonitor) handleEventEnvelopeSent(event types.EnvelopeEvent) { if m.mailServerConfirmation { if !m.isMailserver(event.Peer) { return } } m.mu.Lock() defer m.mu.Unlock() state, ok := m.envelopes[event.Hash] // if we didn't send a message using extension - skip it // if message was already confirmed - skip it if !ok || state == EnvelopeSent { return } m.logger.Debug("envelope is sent", zap.String("hash", event.Hash.String()), zap.String("peer", event.Peer.String())) if event.Batch != (types.Hash{}) { if _, ok := m.batches[event.Batch]; !ok { m.batches[event.Batch] = map[types.Hash]struct{}{} } m.batches[event.Batch][event.Hash] = struct{}{} m.logger.Debug("waiting for a confirmation", zap.String("batch", event.Batch.String())) } else { m.envelopes[event.Hash] = EnvelopeSent if m.handler != nil { m.handler.EnvelopeSent(m.identifiers[event.Hash]) } } } func (m *EnvelopesMonitor) handleAcknowledgedBatch(event types.EnvelopeEvent) { if m.mailServerConfirmation { if !m.isMailserver(event.Peer) { return } } m.mu.Lock() defer m.mu.Unlock() envelopes, ok := m.batches[event.Batch] if !ok { m.logger.Debug("batch is not found", zap.String("batch", event.Batch.String())) } m.logger.Debug("received a confirmation", zap.String("batch", event.Batch.String()), zap.String("peer", event.Peer.String())) envelopeErrors, ok := event.Data.([]types.EnvelopeError) if event.Data != nil && !ok { m.logger.Error("received unexpected data in the the confirmation event", zap.Any("data", event.Data)) } failedEnvelopes := map[types.Hash]struct{}{} for i := range envelopeErrors { envelopeError := envelopeErrors[i] _, exist := m.envelopes[envelopeError.Hash] if exist { m.logger.Warn("envelope that was posted by us is discarded", zap.String("hash", envelopeError.Hash.String()), zap.String("peer", event.Peer.String()), zap.String("error", envelopeError.Description)) var err error switch envelopeError.Code { case types.EnvelopeTimeNotSynced: err = errors.New("envelope wasn't delivered due to time sync issues") } m.handleEnvelopeFailure(envelopeError.Hash, err) } failedEnvelopes[envelopeError.Hash] = struct{}{} } for hash := range envelopes { if _, exist := failedEnvelopes[hash]; exist { continue } state, ok := m.envelopes[hash] if !ok || state == EnvelopeSent { continue } m.envelopes[hash] = EnvelopeSent if m.handler != nil { m.handler.EnvelopeSent(m.identifiers[hash]) } } delete(m.batches, event.Batch) } func (m *EnvelopesMonitor) handleEventEnvelopeExpired(event types.EnvelopeEvent) { m.mu.Lock() defer m.mu.Unlock() m.handleEnvelopeFailure(event.Hash, errors.New("envelope expired due to connectivity issues")) } // handleEnvelopeFailure is a common code path for processing envelopes failures. not thread safe, lock // must be used on a higher level. func (m *EnvelopesMonitor) handleEnvelopeFailure(hash types.Hash, err error) { if state, ok := m.envelopes[hash]; ok { message, exist := m.messages[hash] if !exist { m.logger.Error("message was deleted erroneously", zap.String("envelope hash", hash.String())) } attempt := m.attempts[hash] identifiers := m.identifiers[hash] m.clearMessageState(hash) if state == EnvelopeSent { return } if attempt < m.maxAttempts { m.logger.Debug("retrying to send a message", zap.String("hash", hash.String()), zap.Int("attempt", attempt+1)) hex, err := m.api.Post(context.TODO(), *message) if err != nil { m.logger.Error("failed to retry sending message", zap.String("hash", hash.String()), zap.Int("attempt", attempt+1), zap.Error(err)) if m.handler != nil { m.handler.EnvelopeExpired(identifiers, err) } } envelopeID := types.BytesToHash(hex) m.envelopes[envelopeID] = EnvelopePosted m.messages[envelopeID] = message m.attempts[envelopeID] = attempt + 1 m.identifiers[envelopeID] = identifiers } else { m.logger.Debug("envelope expired", zap.String("hash", hash.String())) if m.handler != nil { m.handler.EnvelopeExpired(identifiers, err) } } } } func (m *EnvelopesMonitor) handleEventEnvelopeReceived(event types.EnvelopeEvent) { if m.mailServerConfirmation { if !m.isMailserver(event.Peer) { return } } m.mu.Lock() defer m.mu.Unlock() state, ok := m.envelopes[event.Hash] if !ok || state != EnvelopePosted { return } m.logger.Debug("expected envelope received", zap.String("hash", event.Hash.String()), zap.String("peer", event.Peer.String())) m.envelopes[event.Hash] = EnvelopeSent if m.handler != nil { m.handler.EnvelopeSent(m.identifiers[event.Hash]) } } // clearMessageState removes all message and envelope state. // not thread-safe, should be protected on a higher level. func (m *EnvelopesMonitor) clearMessageState(envelopeID types.Hash) { delete(m.envelopes, envelopeID) delete(m.messages, envelopeID) delete(m.attempts, envelopeID) delete(m.identifiers, envelopeID) }