Drill 13: Real project — A standard-library HTTP service

package main

import (
    "encoding/json"
    "net/http"
    "time"
)

func health(w http.ResponseWriter, _ *http.Request) {
    w.Header().Set("Content-Type", "application/json")
    json.NewEncoder(w).Encode(map[string]bool{"ok": true})
}

func main() {
    mux := http.NewServeMux()
    mux.HandleFunc("GET /api/health", health)

    server := &http.Server{
        Addr:              ":3000",
        Handler:           mux,
        ReadHeaderTimeout: 5 * time.Second,
    }
    server.ListenAndServe()
}