Golang HTTP并发控制技巧分享

var sem = make(chan struct{}, 10) // 最多允许10个并发
func handler(w http.ResponseWriter, r *http.Request) {
sem <- struct{}{} // 获取令牌
defer func() { <-sem }() // 处理完释放
// 模拟业务处理
time.Sleep(2 * time.Second)
fmt.Fprintf(w, "Request processed")
}

func multiServiceHandler(w http.ResponseWriter, r *http.Request) {
    var wg sync.WaitGroup
    results := make([]string, 3)
wg.Add(3)
go func() { defer wg.Done(); results[0] = callServiceA() }()
go func() { defer wg.Done(); results[1] = callServiceB() }()
go func() { defer wg.Done(); results[2] = callServiceC() }()

wg.Wait() // 等待全部完成
fmt.Fprintf(w, "Results: %v", results)
}

import "golang.org/x/time/rate"
var limiter = rate.NewLimiter(5, 10) // 每秒5个，最多容纳10个突发
func limitMiddleware(next http.HandlerFunc) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
if !limiter.Allow() {
http.StatusText(http.StatusTooManyRequests)
return
}
next(w, r)
}
}
// 使用
http.HandleFunc("/", limitMiddleware(handler))

srv := &http.Server{
    Addr:              ":8080",
    ReadTimeout:       5 * time.Second,
    WriteTimeout:      10 * time.Second,
    IdleTimeout:       30 * time.Second,
    MaxHeaderBytes:    1 << 20,
    Handler:           router,
}
srv.ListenAndServe()