diff --git a/testdata/go_test.mod b/testdata/go_test.mod
index a69baf1..e7dd4ab 100644
--- a/testdata/go_test.mod
+++ b/testdata/go_test.mod
@@ -1,10 +1,12 @@
 module github.com/2manymws/rc
 
-go 1.21.5
+go 1.21.11
+
+toolchain go1.22.3
 
 require (
 	github.com/google/go-cmp v0.6.0
-	github.com/k1LoW/httpstub v0.16.4
+	github.com/k1LoW/httpstub v0.16.5
 )
 
 require (
@@ -13,7 +15,7 @@ require (
 	github.com/dprotaso/go-yit v0.0.0-20220510233725-9ba8df137936 // indirect
 	github.com/mailru/easyjson v0.7.7 // indirect
 	github.com/minio/pkg v1.7.5 // indirect
-	github.com/pb33f/libopenapi v0.16.7 // indirect
+	github.com/pb33f/libopenapi v0.16.8 // indirect
 	github.com/pb33f/libopenapi-validator v0.0.56 // indirect
 	github.com/santhosh-tekuri/jsonschema/v5 v5.3.1 // indirect
 	github.com/vmware-labs/yaml-jsonpath v0.3.2 // indirect
diff --git a/testdata/go_test.sum b/testdata/go_test.sum
index fcba653..9b08fe5 100644
--- a/testdata/go_test.sum
+++ b/testdata/go_test.sum
@@ -36,8 +36,8 @@ github.com/google/pprof v0.0.0-20210407192527-94a9f03dee38/go.mod h1:kpwsk12EmLe
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/ianlancetaylor/demangle v0.0.0-20200824232613-28f6c0f3b639/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
-github.com/k1LoW/httpstub v0.16.4 h1:XM27/PQH/leSthyH/jzMxivAehxUMXVMudah3tDpX74=
-github.com/k1LoW/httpstub v0.16.4/go.mod h1:LJ607j74kHbbtMbkloC9q+0pG3VsJIn8+FwK1jut8Qo=
+github.com/k1LoW/httpstub v0.16.5 h1:PtrOUrYIko6M3nnsKEHtu/bNp8uAh+MrblQ905pnKhA=
+github.com/k1LoW/httpstub v0.16.5/go.mod h1:1vUx0ehYo19Tz8gVaWZ2PWvOPtRyLeQ3ZWYiw5VUmyk=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
 github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
@@ -64,8 +64,8 @@ github.com/onsi/gomega v1.10.1/go.mod h1:iN09h71vgCQne3DLsj+A5owkum+a2tYe+TOCB1y
 github.com/onsi/gomega v1.17.0/go.mod h1:HnhC7FXeEQY45zxNK3PPoIUhzk/80Xly9PcubAlGdZY=
 github.com/onsi/gomega v1.19.0 h1:4ieX6qQjPP/BfC3mpsAtIGGlxTWPeA3Inl/7DtXw1tw=
 github.com/onsi/gomega v1.19.0/go.mod h1:LY+I3pBVzYsTBU1AnDwOSxaYi9WoWiqgwooUqq9yPro=
-github.com/pb33f/libopenapi v0.16.7 h1:kgzBpcX+ESF+C/UUlpqd+H4qdWloBfsDJVMgUmbPDts=
-github.com/pb33f/libopenapi v0.16.7/go.mod h1:PEXNwvtT4KNdjrwudp5OYnD1ryqK6uJ68aMNyWvoMuc=
+github.com/pb33f/libopenapi v0.16.8 h1:EceJ+JTHViwjKNyP3LJ8J39jSQ4F2oOvHw6KfWCcVxM=
+github.com/pb33f/libopenapi v0.16.8/go.mod h1:PEXNwvtT4KNdjrwudp5OYnD1ryqK6uJ68aMNyWvoMuc=
 github.com/pb33f/libopenapi-validator v0.0.56 h1:kYO8DRsSRpnxhUExuEfsgARuT/hkc/ISC77CX0BMze4=
 github.com/pb33f/libopenapi-validator v0.0.56/go.mod h1:Cwdf0GUmnUrbw1LBpcGV1Wx5q/LC9akREV4Jc6/yJDc=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
diff --git a/testutil/rcutil.go b/testutil/rcutil.go
index 192b369..9980373 100644
--- a/testutil/rcutil.go
+++ b/testutil/rcutil.go
@@ -3,53 +3,30 @@ package testutil
 // Copy from github.com/2manymws/rcutil
 
 import (
+	"bufio"
 	"bytes"
-	"io"
 	"net/http"
-	"net/url"
 )
 
 type cachedReqRes struct {
-	Method    string      `json:"method"`
-	Host      string      `json:"host"`
-	URL       string      `json:"url"`
-	ReqHeader http.Header `json:"req_header"`
-	ReqBody   []byte      `json:"req_body"`
-
-	StatusCode int         `json:"status_code"`
-	ResHeader  http.Header `json:"res_header"`
-	ResBody    []byte      `json:"res_body"`
+	req []byte
+	res []byte
 }
 
 // encodeReqRes encodes http.Request and http.Response.
 func encodeReqRes(req *http.Request, res *http.Response) (*cachedReqRes, error) {
-	c := &cachedReqRes{
-		Method:    req.Method,
-		Host:      req.Host,
-		URL:       req.URL.String(),
-		ReqHeader: req.Header,
-
-		StatusCode: res.StatusCode,
-		ResHeader:  res.Header,
+	reqb := &bytes.Buffer{}
+	if err := req.Write(reqb); err != nil {
+		return nil, err
 	}
-	{
-		// FIXME: Use stream
-		b, err := io.ReadAll(req.Body)
-		if err != nil {
-			return nil, err
-		}
-		defer req.Body.Close()
-		c.ReqBody = b
+	resb := &bytes.Buffer{}
+	if err := res.Write(resb); err != nil {
+		return nil, err
 	}
 
-	{
-		// FIXME: Use stream
-		b, err := io.ReadAll(res.Body)
-		if err != nil {
-			return nil, err
-		}
-		defer res.Body.Close()
-		c.ResBody = b
+	c := &cachedReqRes{
+		req: reqb.Bytes(),
+		res: resb.Bytes(),
 	}
 
 	return c, nil
@@ -57,22 +34,15 @@ func encodeReqRes(req *http.Request, res *http.Response) (*cachedReqRes, error)
 
 // decodeReqRes decodes to http.Request and http.Response.
 func decodeReqRes(c *cachedReqRes) (*http.Request, *http.Response, error) {
-	u, err := url.Parse(c.URL)
+	reqb := bytes.NewReader(c.req)
+	req, err := http.ReadRequest(bufio.NewReader(reqb))
 	if err != nil {
 		return nil, nil, err
 	}
-	req := &http.Request{
-		Method: c.Method,
-		Host:   c.Host,
-		URL:    u,
-		Header: c.ReqHeader,
-		Body:   io.NopCloser(bytes.NewReader(c.ReqBody)),
-	}
-	res := &http.Response{
-		Status:     http.StatusText(c.StatusCode),
-		StatusCode: c.StatusCode,
-		Header:     c.ResHeader,
-		Body:       io.NopCloser(bytes.NewReader(c.ResBody)),
+	resb := bytes.NewReader(c.res)
+	res, err := http.ReadResponse(bufio.NewReader(resb), req)
+	if err != nil {
+		return nil, nil, err
 	}
 	return req, res, nil
 }