From 50d443049f3bb083c949c2fc2821d2bc037340d4 Mon Sep 17 00:00:00 2001
From: ginuerzh <ginuerzh@gmail.com>
Date: Wed, 14 Sep 2022 19:53:21 +0800
Subject: [PATCH] add request rate limiter

---
 handler/option.go       | 20 ++++++++++++++------
 limiter/rate/limiter.go | 10 ++++++++++
 metadata/util/util.go   |  2 ++
 3 files changed, 26 insertions(+), 6 deletions(-)
 create mode 100644 limiter/rate/limiter.go

diff --git a/handler/option.go b/handler/option.go
index ad86529..b75ca03 100644
--- a/handler/option.go
+++ b/handler/option.go
@@ -7,17 +7,19 @@ import (
 	"github.com/go-gost/core/auth"
 	"github.com/go-gost/core/bypass"
 	"github.com/go-gost/core/chain"
+	"github.com/go-gost/core/limiter/rate"
 	"github.com/go-gost/core/logger"
 	"github.com/go-gost/core/metadata"
 )
 
 type Options struct {
-	Bypass    bypass.Bypass
-	Router    *chain.Router
-	Auth      *url.Userinfo
-	Auther    auth.Authenticator
-	TLSConfig *tls.Config
-	Logger    logger.Logger
+	Bypass      bypass.Bypass
+	Router      *chain.Router
+	Auth        *url.Userinfo
+	Auther      auth.Authenticator
+	RateLimiter rate.RateLimiter
+	TLSConfig   *tls.Config
+	Logger      logger.Logger
 }
 
 type Option func(opts *Options)
@@ -46,6 +48,12 @@ func AutherOption(auther auth.Authenticator) Option {
 	}
 }
 
+func RateLimiterOption(limiter rate.RateLimiter) Option {
+	return func(opts *Options) {
+		opts.RateLimiter = limiter
+	}
+}
+
 func TLSConfigOption(tlsConfig *tls.Config) Option {
 	return func(opts *Options) {
 		opts.TLSConfig = tlsConfig
diff --git a/limiter/rate/limiter.go b/limiter/rate/limiter.go
new file mode 100644
index 0000000..d92d7bb
--- /dev/null
+++ b/limiter/rate/limiter.go
@@ -0,0 +1,10 @@
+package rate
+
+type Limiter interface {
+	Allow(n int) bool
+	Limit() float64
+}
+
+type RateLimiter interface {
+	Limiter(key string) Limiter
+}
diff --git a/metadata/util/util.go b/metadata/util/util.go
index c45dd21..8772a44 100644
--- a/metadata/util/util.go
+++ b/metadata/util/util.go
@@ -49,6 +49,8 @@ func GetFloat(md metadata.Metadata, key string) (v float64) {
 	}
 
 	switch vv := md.Get(key).(type) {
+	case float64:
+		return vv
 	case int:
 		return float64(vv)
 	case string: