Golang如何实现HTTP请求重试机制_Golang HTTP请求错误处理策略

var resp *http.Response
var err error

for i := 0; i <= maxRetries; i++ {
    resp, err = client.Get(url)
    if err == nil && resp.StatusCode < 500 {
        return resp, nil
    }

    // 判断是否值得重试
    if err != nil {
        log.Printf("请求失败: %v, 重试中... (%d)", err, i+1)
    } else {
        log.Printf("收到状态码: %d, 重试中... (%d)", resp.StatusCode, i+1)
        resp.Body.Close()
    }

    if i == maxRetries {
        break
    }

    // 简单固定延迟，生产环境建议使用指数退避
    time.Sleep(1 * time.Second)
}

return nil, fmt.Errorf("在 %d 次重试后仍失败: %v", maxRetries, err)

for i := 0; i <= maxRetries; i++ {
    resp, err = client.Get(url)
    if err == nil && resp.StatusCode < 500 {
        return resp, nil
    }

    if i < maxRetries {
        // 加入随机抖动（jitter）
        jitter := time.Duration(rand.Int63n(int64(backoff)))
        sleep := backoff + jitter
        time.Sleep(sleep)
        backoff *= 2 // 指数增长
    }

    if resp != nil {
        resp.Body.Close()
    }
}

return nil, fmt.Errorf("最终失败: %v", err)

bo := backoff.NewExponentialBackOff()
bo.MaxElapsedTime = 30 * time.Second

return backoff.Retry(operation, bo)