问如何在重定向初始请求时在gin中记录响应体

EN

func main() {
	r := gin.Default()

	eanAPI := api.NewEanAPI()

  v1 := r.Group("/v1")
	v1.POST("/*action", eanAPI.Redirect, middleware.SaveRequest())
  
  
	port := os.Getenv("PORT")
	if len(port) == 0 {
		port = "8000"
	}
	r.Run(":" + port)
}

func (api *eanAPI) Redirect(ctx *gin.Context) {
	forwardToHost := "https://jsonplaceholder.typicode.com"
	url := ctx.Request.URL.String()
	ctx.Redirect(http.StatusTemporaryRedirect, forwardToHost)
}

type bodyLogWriter struct {
	gin.ResponseWriter
	body *bytes.Buffer
}

func (w bodyLogWriter) Write(b []byte) (int, error) {
	w.body.Write(b)
	return w.ResponseWriter.Write(b)
}

func SaveRequest() gin.HandlerFunc {
	return func(c *gin.Context) {
		c.Next()
		blw := &bodyLogWriter{body: bytes.NewBufferString(""), ResponseWriter: c.Writer}
		c.Writer = blw
		c.Next()
		statusCode := c.Writer.Status()
		fmt.Println("status: ", statusCode)
		if statusCode <= 400 {
			//ok this is an request with error, let's make a record for it
			// now print body (or log in your preferred way)
			fmt.Println("Response body: " + blw.body.String())
		}
 }