角度发送请求时redis崩溃

I have a go server with redigo and I have this function to get data from redis :

func findCompetition(conn redis.Conn, username string) competition{
    conn.Send("KEYS", "*")
    conn.Flush()
    re, erre := conn.Receive()
    keys, err := redis.Strings(re, erre)
    if err != nil {
        log.Print(re)
        log.Print(err)
        return competition{Username:"null"}
    }
    for _, key := range keys {
        comp := getCompetition(conn, key)
        if comp.Competitor == username && 
time.Now().Sub(comp.Time_asked).Minutes() < 2.0 {
            return comp
        }
    }
    return competition{Username:"null"}
}

when I send request by browser like : http://localhost:4500/find_competition/aicam It's ok but when my angular project send request every 1.5sec after some seconds log.Print(err) prints error below :

read tcp 127.0.0.1:35874->127.0.0.1:6379: use of closed network connection

I tried all of the solutions like : stackoverflow github and port 35874 changes sometimes