如何使用Golang优化网络请求超时与重试_Golang HTTP请求性能优化实践

client := &http.Client{
    Timeout: 10 * time.Second,
    Transport: &http.Transport{
        DialContext: (&net.Dialer{
            Timeout:   2 * time.Second,
            KeepAlive: 30 * time.Second,
        }).DialContext,
        TLSHandshakeTimeout:   3 * time.Second,
        ResponseHeaderTimeout: 5 * time.Second,
        MaxIdleConns:          100,
        IdleConnTimeout:       90 * time.Second,
    },
}

func doWithRetry(client *http.Client, req *http.Request, maxRetries int) (*http.Response, error) {
    var resp *http.Response
    var err error
<pre class="brush:php;toolbar:false;"><pre class="brush:php;toolbar:false;">for i := 0; i <= maxRetries; i++ {
    resp, err = client.Do(req)
    if err == nil && resp.StatusCode < 500 {
        return resp, nil
    }

    if i < maxRetries {
        backoff := time.Second * time.Duration(1<<i) // 指数退避：1s, 2s, 4s...
        time.Sleep(backoff)
    }

    // 重试前复制请求体（如果存在）
    if req.Body != nil {
        body, _ := req.GetBody()
        req.Body = body
    }
}
return resp, err

transport := &http.Transport{
    MaxIdleConns:          100,
    MaxIdleConnsPerHost:   20,
    IdleConnTimeout:       90 * time.Second,
    DisableKeepAlives:     false,
}

log.Printf("request failed: %v, retrying in %v", err, backoff)