status-protocol-go/transport/whisper/envelopes.go

311 lines
9.3 KiB
Go

package whisper
import (
"context"
"errors"
"sync"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/p2p/enode"
whisper "github.com/status-im/whisper/whisperv6"
"go.uber.org/zap"
)
// 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 whisper queue.
EnvelopePosted EnvelopeState = iota
// EnvelopeSent is set when envelope is sent to atleast one peer.
EnvelopeSent
)
type EnvelopesMonitorConfig struct {
EnvelopeEventsHandler EnvelopeEventsHandler
MaxAttempts int
MailserverConfirmationsEnabled bool
IsMailserver func(enode.ID) bool
Logger *zap.Logger
}
// EnvelopeEventsHandler used for two different event types.
type EnvelopeEventsHandler interface {
EnvelopeSent([][]byte)
EnvelopeExpired([][]byte, error)
MailServerRequestCompleted(common.Hash, common.Hash, []byte, error)
MailServerRequestExpired(common.Hash)
}
// NewEnvelopesMonitor returns a pointer to an instance of the EnvelopesMonitor.
func NewEnvelopesMonitor(w *whisper.Whisper, config *EnvelopesMonitorConfig) *EnvelopesMonitor {
logger := config.Logger
if logger == nil {
logger = zap.NewNop()
}
return &EnvelopesMonitor{
w: w,
whisperAPI: whisper.NewPublicWhisperAPI(w),
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[common.Hash]EnvelopeState{},
messages: map[common.Hash]whisper.NewMessage{},
attempts: map[common.Hash]int{},
identifiers: make(map[common.Hash][][]byte),
// key is hash of the batch (event.Batch)
batches: map[common.Hash]map[common.Hash]struct{}{},
}
}
// EnvelopesMonitor is responsible for monitoring whisper envelopes state.
type EnvelopesMonitor struct {
w *whisper.Whisper
whisperAPI *whisper.PublicWhisperAPI
handler EnvelopeEventsHandler
mailServerConfirmation bool
maxAttempts int
mu sync.Mutex
envelopes map[common.Hash]EnvelopeState
batches map[common.Hash]map[common.Hash]struct{}
messages map[common.Hash]whisper.NewMessage
attempts map[common.Hash]int
identifiers map[common.Hash][][]byte
wg sync.WaitGroup
quit chan struct{}
isMailserver func(peer enode.ID) 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 common.Hash, message whisper.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 common.Hash) EnvelopeState {
m.mu.Lock()
defer m.mu.Unlock()
state, exist := m.envelopes[hash]
if !exist {
return NotRegistered
}
return state
}
// handleEnvelopeEvents processes whisper envelope events
func (m *EnvelopesMonitor) handleEnvelopeEvents() {
events := make(chan whisper.EnvelopeEvent, 100) // must be buffered to prevent blocking whisper
sub := m.w.SubscribeEnvelopeEvents(events)
defer 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 whisper.EnvelopeEvent) {
handlers := map[whisper.EventType]func(whisper.EnvelopeEvent){
whisper.EventEnvelopeSent: m.handleEventEnvelopeSent,
whisper.EventEnvelopeExpired: m.handleEventEnvelopeExpired,
whisper.EventBatchAcknowledged: m.handleAcknowledgedBatch,
whisper.EventEnvelopeReceived: m.handleEventEnvelopeReceived,
}
if handler, ok := handlers[event.Event]; ok {
handler(event)
}
}
func (m *EnvelopesMonitor) handleEventEnvelopeSent(event whisper.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 != (common.Hash{}) {
if _, ok := m.batches[event.Batch]; !ok {
m.batches[event.Batch] = map[common.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 whisper.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.([]whisper.EnvelopeError)
if event.Data != nil && !ok {
m.logger.Error("received unexpected data in the the confirmation event", zap.String("batch", event.Batch.String()))
}
failedEnvelopes := map[common.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 whisper.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 whisper.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 common.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.whisperAPI.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 := common.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 whisper.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 common.Hash) {
delete(m.envelopes, envelopeID)
delete(m.messages, envelopeID)
delete(m.attempts, envelopeID)
delete(m.identifiers, envelopeID)
}