func getLoadBalanceAddr() string {
	return RealAddr[0]
}
a fake function that we can do strategy here.
package main
import (
	"bufio"
	"log"
	"net/http"
	"net/url"
	"github.com/gin-gonic/gin"
)
const (
	ReverseServerAddr = "127.0.0.1:2002"
)
var (
	RealAddr = []string{
		"http://127.0.0.1:2003",
	}
)