perf: reuse zlib.Writer

okhowang · weijunyi · commit 1403f743b5b4 · 2024-11-19T14:50:37.000+08:00
before:
BenchmarkGenSig
BenchmarkGenSig-16                          7788            150884 ns/op          817750 B/op         62 allocs/op
BenchmarkGenUserSigWithBuf
BenchmarkGenUserSigWithBuf-16               7298            140476 ns/op          818145 B/op         68 allocs/op

after:
BenchmarkGenSig
BenchmarkGenSig-16               	   39601	     30510 ns/op	    3896 B/op	      42 allocs/op
BenchmarkGenUserSigWithBuf
BenchmarkGenUserSigWithBuf-16    	   38188	     31464 ns/op	    4064 B/op	      48 allocs/op
diff --git a/tencentyun/TLSSigAPI.go b/tencentyun/TLSSigAPI.go
@@ -8,8 +8,10 @@ import (
 	"encoding/base64"
 	"encoding/json"
 	"errors"
+	"io"
 	"io/ioutil"
 	"strconv"
+	"sync"
 	"time"
 )
 
@@ -23,7 +25,7 @@ import (
  * expire - UserSig 票据的过期时间，单位是秒，比如 86400 代表生成的 UserSig 票据在一天后就无法再使用了。
  */
 
- /**
+/**
  * Function: Used to issue UserSig that is required by the TRTC and IM services.
  *
  * Parameter description:
@@ -94,7 +96,6 @@ func GenUserSigWithBuf(sdkappid int, key string, userid string, expire int, buf
  *  - privilegeMap == 0010 1010 == 42: Indicates that the UserID has only the permissions to enter the room and receive audio/video data.
  */
 
-
 func GenPrivateMapKey(sdkappid int, key string, userid string, expire int, roomid uint32, privilegeMap uint32) (string, error) {
 	var userbuf []byte = genUserBuf(userid, sdkappid, roomid, expire, privilegeMap, 0, "")
 	return genSig(sdkappid, key, userid, expire, userbuf)
@@ -290,7 +291,8 @@ func genSig(sdkappid int, key string, identifier string, expire int, userbuf []b
 	}
 
 	var b bytes.Buffer
-	w := zlib.NewWriter(&b)
+	w := newZlibWriter(&b)
+	defer zlibWriterPool.Put(w)
 	if _, err = w.Write(data); err != nil {
 		return "", err
 	}
@@ -413,3 +415,17 @@ var (
 	ErrUserBufNotMatch     = errors.New("userbuf not match")
 	ErrSigNotMatch         = errors.New("sig not match")
 )
+
+var (
+	zlibWriterPool sync.Pool
+)
+
+func newZlibWriter(w io.Writer) *zlib.Writer {
+	v := zlibWriterPool.Get()
+	if v == nil {
+		return zlib.NewWriter(w)
+	}
+	zw := v.(*zlib.Writer)
+	zw.Reset(w)
+	return zw
+}
