status-go/protocol/transport/envelopes_monitor.go

437 lines
12 KiB
Go

package transport
import (
"context"
"errors"
"math"
"sync"
"time"
"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
AwaitOnlyMailServerConfirmations 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,
awaitOnlyMailServerConfirmations: config.AwaitOnlyMailServerConfirmations,
maxAttempts: config.MaxAttempts,
isMailserver: config.IsMailserver,
logger: logger.With(zap.Namespace("EnvelopesMonitor")),
// key is envelope hash (event.Hash)
envelopes: map[types.Hash]*monitoredEnvelope{},
// key is hash of the batch (event.Batch)
batches: map[types.Hash]map[types.Hash]struct{}{},
// key is stringified message identifier
messageEnvelopeHashes: make(map[string][]types.Hash),
}
}
type monitoredEnvelope struct {
envelopeHashID types.Hash
state EnvelopeState
attempts int
message *types.NewMessage
messageIDs [][]byte
lastAttemptTime time.Time
}
// EnvelopesMonitor is responsible for monitoring waku envelopes state.
type EnvelopesMonitor struct {
w types.Waku
api types.PublicWakuAPI
handler EnvelopeEventsHandler
maxAttempts int
mu sync.Mutex
envelopes map[types.Hash]*monitoredEnvelope
retryQueue []*monitoredEnvelope
batches map[types.Hash]map[types.Hash]struct{}
messageEnvelopeHashes map[string][]types.Hash
awaitOnlyMailServerConfirmations bool
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(2)
go func() {
m.handleEnvelopeEvents()
m.wg.Done()
}()
go func() {
defer m.wg.Done()
m.retryLoop()
}()
}
// Stop process events.
func (m *EnvelopesMonitor) Stop() {
close(m.quit)
m.wg.Wait()
}
// Add hashes to a tracker.
// Identifiers may be backed by multiple envelopes. It happens when message is split in segmentation layer.
func (m *EnvelopesMonitor) Add(messageIDs [][]byte, envelopeHashes []types.Hash, messages []*types.NewMessage) error {
if len(envelopeHashes) != len(messages) {
return errors.New("hashes don't match messages")
}
m.mu.Lock()
defer m.mu.Unlock()
for _, messageID := range messageIDs {
m.messageEnvelopeHashes[types.HexBytes(messageID).String()] = envelopeHashes
}
for i, envelopeHash := range envelopeHashes {
if _, ok := m.envelopes[envelopeHash]; !ok {
m.envelopes[envelopeHash] = &monitoredEnvelope{
envelopeHashID: envelopeHash,
state: EnvelopePosted,
attempts: 1,
lastAttemptTime: time.Now(),
message: messages[i],
messageIDs: messageIDs,
}
}
}
m.processMessageIDs(messageIDs)
return nil
}
func (m *EnvelopesMonitor) GetState(hash types.Hash) EnvelopeState {
m.mu.Lock()
defer m.mu.Unlock()
envelope, exist := m.envelopes[hash]
if !exist {
return NotRegistered
}
return envelope.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() {
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) {
// Mailserver confirmations for WakuV2 are disabled
if (m.w == nil || m.w.Version() < 2) && m.awaitOnlyMailServerConfirmations {
if !m.isMailserver(event.Peer) {
return
}
}
m.mu.Lock()
defer m.mu.Unlock()
confirmationExpected := event.Batch != (types.Hash{})
envelope, ok := m.envelopes[event.Hash]
// If confirmations are not expected, we keep track of the envelope
// being sent
if !ok && !confirmationExpected {
m.envelopes[event.Hash] = &monitoredEnvelope{envelopeHashID: event.Hash, state: EnvelopeSent}
return
}
// if message was already confirmed - skip it
if envelope.state == EnvelopeSent {
return
}
m.logger.Debug("envelope is sent", zap.String("hash", event.Hash.String()), zap.String("peer", event.Peer.String()))
if confirmationExpected {
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.logger.Debug("confirmation not expected, marking as sent")
envelope.state = EnvelopeSent
m.processMessageIDs(envelope.messageIDs)
}
}
func (m *EnvelopesMonitor) handleAcknowledgedBatch(event types.EnvelopeEvent) {
if m.awaitOnlyMailServerConfirmations && !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
}
envelope, ok := m.envelopes[hash]
if !ok || envelope.state == EnvelopeSent {
continue
}
envelope.state = EnvelopeSent
m.processMessageIDs(envelope.messageIDs)
}
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 envelope, ok := m.envelopes[hash]; ok {
m.clearMessageState(hash)
if envelope.state == EnvelopeSent {
return
}
if envelope.attempts < m.maxAttempts {
m.retryQueue = append(m.retryQueue, envelope)
} else {
m.logger.Debug("envelope expired", zap.String("hash", hash.String()))
m.removeFromRetryQueue(hash)
if m.handler != nil {
m.handler.EnvelopeExpired(envelope.messageIDs, err)
}
}
}
}
func backoffDuration(attempts int) time.Duration {
baseDelay := 1 * time.Second
maxDelay := 30 * time.Second
backoff := baseDelay * time.Duration(math.Pow(2, float64(attempts)))
if backoff > maxDelay {
backoff = maxDelay
}
return backoff
}
// retryLoop handles the retry logic to send envelope in a loop
func (m *EnvelopesMonitor) retryLoop() {
ticker := time.NewTicker(500 * time.Millisecond) // Timer, triggers every 500 milliseconds
defer ticker.Stop()
for {
select {
case <-m.quit:
return
case <-ticker.C:
m.retryOnce()
}
}
}
// retryOnce retries once
func (m *EnvelopesMonitor) retryOnce() {
m.mu.Lock()
defer m.mu.Unlock()
for _, envelope := range m.retryQueue {
if envelope.attempts < m.maxAttempts {
elapsed := time.Since(envelope.lastAttemptTime)
if elapsed < backoffDuration(envelope.attempts) {
continue
}
m.logger.Debug("retrying to send a message", zap.String("hash", envelope.envelopeHashID.String()), zap.Int("attempt", envelope.attempts+1))
hex, err := m.api.Post(context.TODO(), *envelope.message)
if err != nil {
m.logger.Error("failed to retry sending message", zap.String("hash", envelope.envelopeHashID.String()), zap.Int("attempt", envelope.attempts+1), zap.Error(err))
if m.handler != nil {
m.handler.EnvelopeExpired(envelope.messageIDs, err)
}
} else {
m.removeFromRetryQueue(envelope.envelopeHashID)
envelope.envelopeHashID = types.BytesToHash(hex)
}
envelope.state = EnvelopePosted
envelope.attempts++
envelope.lastAttemptTime = time.Now()
m.envelopes[envelope.envelopeHashID] = envelope
}
}
}
// removeFromRetryQueue removes the specified envelope from the retry queue
func (m *EnvelopesMonitor) removeFromRetryQueue(envelopeID types.Hash) {
var newRetryQueue []*monitoredEnvelope
for _, envelope := range m.retryQueue {
if envelope.envelopeHashID != envelopeID {
newRetryQueue = append(newRetryQueue, envelope)
}
}
m.retryQueue = newRetryQueue
}
func (m *EnvelopesMonitor) handleEventEnvelopeReceived(event types.EnvelopeEvent) {
if m.awaitOnlyMailServerConfirmations && !m.isMailserver(event.Peer) {
return
}
m.mu.Lock()
defer m.mu.Unlock()
envelope, ok := m.envelopes[event.Hash]
if !ok || envelope.state != EnvelopePosted {
return
}
m.logger.Debug("expected envelope received", zap.String("hash", event.Hash.String()), zap.String("peer", event.Peer.String()))
envelope.state = EnvelopeSent
m.processMessageIDs(envelope.messageIDs)
}
func (m *EnvelopesMonitor) processMessageIDs(messageIDs [][]byte) {
sentMessageIDs := make([][]byte, 0, len(messageIDs))
for _, messageID := range messageIDs {
hashes, ok := m.messageEnvelopeHashes[types.HexBytes(messageID).String()]
if !ok {
continue
}
sent := true
// Consider message as sent if all corresponding envelopes are in EnvelopeSent state
for _, hash := range hashes {
envelope, ok := m.envelopes[hash]
if !ok || envelope.state != EnvelopeSent {
sent = false
break
}
}
if sent {
sentMessageIDs = append(sentMessageIDs, messageID)
}
}
if len(sentMessageIDs) > 0 && m.handler != nil {
m.handler.EnvelopeSent(sentMessageIDs)
}
}
// clearMessageState removes all message and envelope state.
// not thread-safe, should be protected on a higher level.
func (m *EnvelopesMonitor) clearMessageState(envelopeID types.Hash) {
envelope, ok := m.envelopes[envelopeID]
if !ok {
return
}
delete(m.envelopes, envelopeID)
for _, messageID := range envelope.messageIDs {
delete(m.messageEnvelopeHashes, types.HexBytes(messageID).String())
}
}