HTTP server graceful shutdown

Calling os.Exit or letting main() return immediately kills in-flight HTTP requests. A graceful shutdown waits for active connections to complete.

Use http.Server.Shutdown with a context and signal handling:

func main() {
    srv := &http.Server{Addr: ":8080", Handler: myHandler()}

    // Start server in goroutine
    go func() {
        if err := srv.ListenAndServe(); err != http.ErrServerClosed {
            log.Fatalf("ListenAndServe: %v", err)
        }
    }()

    // Wait for interrupt signal
    quit := make(chan os.Signal, 1)
    signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
    <-quit
    log.Println("Shutting down...")

    ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
    defer cancel()

    if err := srv.Shutdown(ctx); err != nil {
        log.Fatalf("Shutdown: %v", err)
    }
    log.Println("Server exited")
}

Shutdown closes the listener immediately (no new connections) then waits for active connections to finish. If the context deadline passes before all connections close, it returns an error.