status-go/wakuv2/filter_manager.go

365 lines
11 KiB
Go

package wakuv2
import (
"context"
"crypto/rand"
"errors"
"math/big"
"sync"
"time"
"github.com/google/uuid"
"github.com/libp2p/go-libp2p/core/peer"
"github.com/status-im/status-go/wakuv2/common"
node "github.com/waku-org/go-waku/waku/v2/node"
"github.com/waku-org/go-waku/waku/v2/protocol"
"github.com/waku-org/go-waku/waku/v2/protocol/filter"
"github.com/waku-org/go-waku/waku/v2/protocol/relay"
"github.com/waku-org/go-waku/waku/v2/protocol/subscription"
"go.uber.org/zap"
"golang.org/x/exp/maps"
)
const (
FilterEventAdded = iota
FilterEventRemoved
FilterEventPingResult
FilterEventSubscribeResult
FilterEventUnsubscribeResult
FilterEventGetStats
)
const pingTimeout = 10 * time.Second
type FilterSubs map[string]subscription.SubscriptionSet
type FilterEvent struct {
eventType int
filterID string
success bool
peerID peer.ID
tempID string
sub *subscription.SubscriptionDetails
ch chan FilterSubs
}
// Methods on FilterManager maintain filter peer health
//
// runFilterLoop is the main event loop
//
// Filter Install/Uninstall events are pushed onto eventChan
// Subscribe, UnsubscribeWithSubscription, IsSubscriptionAlive calls
// are invoked from goroutines and request results pushed onto eventChan
//
// filterSubs is the map of filter IDs to subscriptions
type FilterManager struct {
ctx context.Context
filterSubs FilterSubs
eventChan chan (FilterEvent)
isFilterSubAlive func(sub *subscription.SubscriptionDetails) error
getFilter func(string) *common.Filter
onNewEnvelopes func(env *protocol.Envelope) error
peers []peer.ID
logger *zap.Logger
settings settings
node *node.WakuNode
}
func newFilterManager(ctx context.Context, logger *zap.Logger, getFilterFn func(string) *common.Filter, settings settings, onNewEnvelopes func(env *protocol.Envelope) error, node *node.WakuNode) *FilterManager {
// This fn is being mocked in test
mgr := new(FilterManager)
mgr.ctx = ctx
mgr.logger = logger
mgr.getFilter = getFilterFn
mgr.onNewEnvelopes = onNewEnvelopes
mgr.filterSubs = make(FilterSubs)
mgr.eventChan = make(chan FilterEvent, 100)
mgr.peers = make([]peer.ID, 0)
mgr.settings = settings
mgr.node = node
mgr.isFilterSubAlive = func(sub *subscription.SubscriptionDetails) error {
ctx, cancel := context.WithTimeout(ctx, pingTimeout)
defer cancel()
return mgr.node.FilterLightnode().IsSubscriptionAlive(ctx, sub)
}
return mgr
}
func (mgr *FilterManager) runFilterLoop(wg *sync.WaitGroup) {
defer wg.Done()
// Use it to ping filter peer(s) periodically
ticker := time.NewTicker(5 * time.Second)
defer ticker.Stop()
// Populate filter peers initially
mgr.peers = mgr.findFilterPeers() // ordered list of peers to select from
for {
select {
case <-mgr.ctx.Done():
return
case <-ticker.C:
mgr.peers = mgr.findFilterPeers()
mgr.pingPeers()
case ev := <-mgr.eventChan:
mgr.processEvents(&ev)
}
}
}
func (mgr *FilterManager) processEvents(ev *FilterEvent) {
switch ev.eventType {
case FilterEventAdded:
mgr.filterSubs[ev.filterID] = make(subscription.SubscriptionSet)
mgr.resubscribe(ev.filterID)
case FilterEventRemoved:
for _, sub := range mgr.filterSubs[ev.filterID] {
if sub == nil {
// Skip temp subs
continue
}
go mgr.unsubscribeFromFilter(ev.filterID, sub)
}
delete(mgr.filterSubs, ev.filterID)
case FilterEventPingResult:
if ev.success {
break
}
// filterID field is only set when there are no subs to check for this filter,
// therefore no particular peers that could be unreachable.
if ev.filterID != "" {
// Trigger full resubscribe, filter has no peers
mgr.logger.Debug("filter has no subs", zap.String("filterId", ev.filterID))
mgr.resubscribe(ev.filterID)
break
}
// Remove peer from list
for i, p := range mgr.peers {
if ev.peerID == p {
mgr.peers = append(mgr.peers[:i], mgr.peers[i+1:]...)
break
}
}
// Delete subs for removed peer
for filterID, subs := range mgr.filterSubs {
for _, sub := range subs {
if sub == nil {
// Skip temp subs
continue
}
if sub.PeerID == ev.peerID {
mgr.logger.Debug("filter sub is inactive", zap.String("filterId", filterID), zap.String("subID", sub.ID))
delete(subs, sub.ID)
go mgr.unsubscribeFromFilter(filterID, sub)
}
}
mgr.resubscribe(filterID)
}
case FilterEventSubscribeResult:
subs, found := mgr.filterSubs[ev.filterID]
if ev.success {
if found {
subs[ev.sub.ID] = ev.sub
go mgr.runFilterSubscriptionLoop(ev.sub)
} else {
// We subscribed to a filter that is already uninstalled; invoke unsubscribe
go mgr.unsubscribeFromFilter(ev.filterID, ev.sub)
}
}
if found {
// Delete temp subscription record
delete(subs, ev.tempID)
}
case FilterEventUnsubscribeResult:
mgr.logger.Debug("filter event unsubscribe_result", zap.String("filterId", ev.filterID), zap.Stringer("peerID", ev.sub.PeerID))
case FilterEventGetStats:
stats := make(FilterSubs)
for id, subs := range mgr.filterSubs {
stats[id] = make(subscription.SubscriptionSet)
for subID, sub := range subs {
if sub == nil {
// Skip temp subs
continue
}
stats[id][subID] = sub
}
}
ev.ch <- stats
}
}
func (mgr *FilterManager) subscribeToFilter(filterID string, peer peer.ID, tempID string) {
f := mgr.getFilter(filterID)
if f == nil {
mgr.logger.Error("filter subscribeToFilter: No filter found", zap.String("id", filterID))
mgr.eventChan <- FilterEvent{eventType: FilterEventSubscribeResult, filterID: filterID, tempID: tempID, success: false}
return
}
contentFilter := mgr.buildContentFilter(f.PubsubTopic, f.ContentTopics)
mgr.logger.Debug("filter subscribe to filter node", zap.Stringer("peer", peer), zap.String("pubsubTopic", contentFilter.PubsubTopic), zap.Strings("contentTopics", contentFilter.ContentTopicsList()))
ctx, cancel := context.WithTimeout(mgr.ctx, requestTimeout)
defer cancel()
subDetails, err := mgr.node.FilterLightnode().Subscribe(ctx, contentFilter, filter.WithPeer(peer))
var sub *subscription.SubscriptionDetails
if err != nil {
mgr.logger.Warn("filter could not add wakuv2 filter for peer", zap.String("filterId", filterID), zap.Stringer("peer", peer), zap.Error(err))
} else {
mgr.logger.Debug("filter subscription success", zap.String("filterId", filterID), zap.Stringer("peer", peer), zap.String("pubsubTopic", contentFilter.PubsubTopic), zap.Strings("contentTopics", contentFilter.ContentTopicsList()))
sub = subDetails[0]
}
success := err == nil
mgr.eventChan <- FilterEvent{eventType: FilterEventSubscribeResult, filterID: filterID, tempID: tempID, sub: sub, success: success}
}
func (mgr *FilterManager) unsubscribeFromFilter(filterID string, sub *subscription.SubscriptionDetails) {
mgr.logger.Debug("filter unsubscribe from filter node", zap.String("filterId", filterID), zap.String("subId", sub.ID), zap.Stringer("peer", sub.PeerID))
// Unsubscribe on light node
ctx, cancel := context.WithTimeout(mgr.ctx, requestTimeout)
defer cancel()
_, err := mgr.node.FilterLightnode().UnsubscribeWithSubscription(ctx, sub)
if err != nil {
mgr.logger.Warn("could not unsubscribe wakuv2 filter for peer", zap.String("filterId", filterID), zap.String("subId", sub.ID), zap.Error(err))
}
success := err == nil
mgr.eventChan <- FilterEvent{eventType: FilterEventUnsubscribeResult, filterID: filterID, success: success, sub: sub}
}
// Check whether each of the installed filters
// has enough alive subscriptions to peers
func (mgr *FilterManager) pingPeers() {
mgr.logger.Debug("filter pingPeers")
distinctPeers := make(map[peer.ID]struct{})
for filterID, subs := range mgr.filterSubs {
if len(subs) == 0 {
// No subs found, trigger full resubscribe
mgr.logger.Debug("filter ping peer no subs", zap.String("filterId", filterID))
go func() {
mgr.eventChan <- FilterEvent{eventType: FilterEventPingResult, filterID: filterID, success: false}
}()
continue
}
for _, sub := range subs {
if sub == nil {
// Skip temp subs
continue
}
_, found := distinctPeers[sub.PeerID]
if found {
continue
}
distinctPeers[sub.PeerID] = struct{}{}
mgr.logger.Debug("filter ping peer", zap.Stringer("peerId", sub.PeerID))
go func(sub *subscription.SubscriptionDetails) {
err := mgr.isFilterSubAlive(sub)
alive := err == nil
if alive {
mgr.logger.Debug("filter aliveness check succeeded", zap.Stringer("peerId", sub.PeerID))
} else {
mgr.logger.Debug("filter aliveness check failed", zap.Stringer("peerId", sub.PeerID), zap.Error(err))
}
mgr.eventChan <- FilterEvent{eventType: FilterEventPingResult, peerID: sub.PeerID, success: alive}
}(sub)
}
}
}
func (mgr *FilterManager) buildContentFilter(pubsubTopic string, contentTopicSet common.TopicSet) protocol.ContentFilter {
contentTopics := make([]string, len(contentTopicSet))
for i, ct := range maps.Keys(contentTopicSet) {
contentTopics[i] = ct.ContentTopic()
}
return protocol.ContentFilter{
PubsubTopic: pubsubTopic,
ContentTopics: protocol.NewContentTopicSet(contentTopics...),
}
}
// Find suitable peer(s)
func (mgr *FilterManager) findFilterPeers() []peer.ID {
allPeers := mgr.node.Host().Peerstore().Peers()
peers := make([]peer.ID, 0)
for _, peer := range allPeers {
protocols, err := mgr.node.Host().Peerstore().SupportsProtocols(peer, filter.FilterSubscribeID_v20beta1, relay.WakuRelayID_v200)
if err != nil {
mgr.logger.Debug("SupportsProtocols error", zap.Error(err))
continue
}
if len(protocols) == 2 {
peers = append(peers, peer)
}
}
mgr.logger.Debug("Filtered peers", zap.Int("cnt", len(peers)))
return peers
}
func (mgr *FilterManager) findPeerCandidate() (peer.ID, error) {
if len(mgr.peers) == 0 {
return "", errors.New("filter could not select a suitable peer")
}
n, _ := rand.Int(rand.Reader, big.NewInt(int64(len(mgr.peers))))
return mgr.peers[n.Int64()], nil
}
func (mgr *FilterManager) resubscribe(filterID string) {
subs, found := mgr.filterSubs[filterID]
if !found {
mgr.logger.Error("resubscribe filter not found", zap.String("filterId", filterID))
return
}
mgr.logger.Debug("filter active subscriptions count:", zap.String("filterId", filterID), zap.Int("len", len(subs)))
for i := len(subs); i < mgr.settings.MinPeersForFilter; i++ {
mgr.logger.Debug("filter check not passed, try subscribing to peers", zap.String("filterId", filterID))
peer, err := mgr.findPeerCandidate()
if err == nil {
// Create sub placeholder in order to avoid potentially too many subs
tempID := uuid.NewString()
subs[tempID] = nil
go mgr.subscribeToFilter(filterID, peer, tempID)
} else {
mgr.logger.Error("filter resubscribe findPeer error", zap.Error(err))
}
}
}
func (mgr *FilterManager) runFilterSubscriptionLoop(sub *subscription.SubscriptionDetails) {
for {
select {
case <-mgr.ctx.Done():
return
case env, ok := <-sub.C:
if ok {
err := (mgr.onNewEnvelopes)(env)
if err != nil {
mgr.logger.Error("OnNewEnvelopes error", zap.Error(err))
}
} else {
mgr.logger.Debug("filter sub is closed", zap.String("id", sub.ID))
return
}
}
}
}