You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
112 lines
2.5 KiB
112 lines
2.5 KiB
package ratelimiter
|
|
|
|
import (
|
|
"sync"
|
|
|
|
"github.com/prometheus/client_golang/prometheus"
|
|
|
|
"github.com/ethereum/go-ethereum/event"
|
|
|
|
"github.com/harmony-one/harmony/p2p/stream/common/streammanager"
|
|
sttypes "github.com/harmony-one/harmony/p2p/stream/types"
|
|
p2ptypes "github.com/harmony-one/harmony/p2p/types"
|
|
"go.uber.org/ratelimit"
|
|
)
|
|
|
|
// RateLimiter is the interface to limit the incoming request.
|
|
// The purpose of rate limiter is to prevent the node from running out of resource
|
|
// for consensus on DDoS attacks.
|
|
type RateLimiter interface {
|
|
LimitRequest(stid sttypes.StreamID)
|
|
|
|
p2ptypes.LifeCycle
|
|
}
|
|
|
|
// rateLimiter is the implementation of RateLimiter.
|
|
// The rateLimiter limit request rate:
|
|
// 1. For global stream requests
|
|
// 2. For requests from a stream
|
|
//
|
|
// TODO: make request weighted in rate limiter
|
|
type rateLimiter struct {
|
|
globalLimiter ratelimit.Limiter
|
|
|
|
streamRate int
|
|
limiters map[sttypes.StreamID]ratelimit.Limiter
|
|
sm streammanager.Subscriber
|
|
|
|
lock sync.RWMutex
|
|
closeC chan struct{}
|
|
}
|
|
|
|
// NewRateLimiter creates a new rate limiter
|
|
func NewRateLimiter(sm streammanager.Subscriber, global, single int) RateLimiter {
|
|
return &rateLimiter{
|
|
globalLimiter: ratelimit.New(global),
|
|
|
|
streamRate: single,
|
|
limiters: make(map[sttypes.StreamID]ratelimit.Limiter),
|
|
sm: sm,
|
|
|
|
closeC: make(chan struct{}),
|
|
}
|
|
}
|
|
|
|
// Start start the rate limiter
|
|
func (rl *rateLimiter) Start() {
|
|
rmStC := make(chan streammanager.EvtStreamRemoved)
|
|
sub := rl.sm.SubscribeRemoveStreamEvent(rmStC)
|
|
|
|
go rl.rmStreamLoop(rmStC, sub)
|
|
}
|
|
|
|
// Close close the rate limiter
|
|
func (rl *rateLimiter) Close() {
|
|
close(rl.closeC)
|
|
}
|
|
|
|
func (rl *rateLimiter) rmStreamLoop(rmStC chan streammanager.EvtStreamRemoved, sub event.Subscription) {
|
|
defer sub.Unsubscribe()
|
|
|
|
for {
|
|
select {
|
|
case evt := <-rmStC:
|
|
stid := evt.ID
|
|
rl.unRegStream(stid)
|
|
|
|
case <-rl.closeC:
|
|
return
|
|
}
|
|
}
|
|
}
|
|
|
|
func (rl *rateLimiter) LimitRequest(stid sttypes.StreamID) {
|
|
serverRequestCounter.Inc()
|
|
timer := prometheus.NewTimer(serverRequestDelayDuration)
|
|
defer timer.ObserveDuration()
|
|
|
|
rl.lock.RLock()
|
|
limiter, ok := rl.limiters[stid]
|
|
rl.lock.RUnlock()
|
|
|
|
// double lock to ensure concurrency
|
|
if !ok {
|
|
rl.lock.Lock()
|
|
if limiter2, ok := rl.limiters[stid]; ok {
|
|
limiter = limiter2
|
|
} else {
|
|
limiter = ratelimit.New(rl.streamRate)
|
|
rl.limiters[stid] = limiter
|
|
}
|
|
rl.lock.Unlock()
|
|
}
|
|
|
|
rl.globalLimiter.Take()
|
|
limiter.Take()
|
|
}
|
|
|
|
func (rl *rateLimiter) unRegStream(stid sttypes.StreamID) {
|
|
rl.lock.Lock()
|
|
delete(rl.limiters, stid)
|
|
defer rl.lock.Unlock()
|
|
}
|
|
|