An HTTP handler in Go

Serving JSON with net/http and ServeMux.

func handleHealth(w http.ResponseWriter, r *http.Request) {
    if r.Method != http.MethodGet {
        http.Error(w, "not allowed", http.StatusMethodNotAllowed)
        return
    }
    w.Header().Set("Content-Type", "application/json")
    json.NewEncoder(w).Encode(map[string]string{"status": "ok"})
}

func routes() *http.ServeMux {
    mux := http.NewServeMux()
    mux.HandleFunc("/healthz", handleHealth)
    return mux
}

How it works

1. A handler takes a ResponseWriter and Request.
2. Method checks reject the wrong verb.
3. ServeMux routes paths to handlers.

Keywords and builtins used here

• func
• if
• map
• return
• string

The run, in numbers

Lines

14

Characters to type

384

Tokens

98

Three-star pace

110 tpm

At the three-star pace of 110 tokens a minute, this run takes about 53 seconds.

Type this snippet

Step 2 of 5 in HTTP, step 17 of 26 in Standard library & project layout.

← Previous Next →