code: func (ctx *Context) RemoteAddr() string {
  	addr := ctx.Req.Header.Get("X-Real-IP")
  	if len(addr) == 0 {
  		addr = ctx.Req.Header.Get("X-Forwarded-For")
  		if addr == "" {
  			addr = ctx.Req.RemoteAddr
  			if i := strings.LastIndex(addr, ":"); i > -1 {
  				addr = addr[:i]
  			}
  		}
  	}
  	return addr
  }
docs: // RemoteAddr returns more real IP address.