drone-example/main.go

package main

import (
	"encoding/json"
	"log"
	"mime"
	"net/http"
	"strconv"

	"git.phc.dm.unipi.it/phc/drone-example/foo"
)

func main() {
	r := http.NewServeMux()
	r.HandleFunc("/foo/sum", func(w http.ResponseWriter, r *http.Request) {
		if r.Method != http.MethodGet {
			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
			return
		}

		aStr := r.URL.Query().Get("a")
		bStr := r.URL.Query().Get("b")

		a, err := strconv.Atoi(aStr)
		if err != nil {
			http.Error(w, `the query param "a" must be an integer`, http.StatusUnprocessableEntity)
			return
		}

		b, err := strconv.Atoi(bStr)
		if err != nil {
			http.Error(w, `the query param "b" must be an integer`, http.StatusUnprocessableEntity)
			return
		}

		result := foo.Sum(a, b)

		w.Header().Set("Content-Type", mime.TypeByExtension(".json"))
		if err := json.NewEncoder(w).Encode(result); err != nil {
			log.Fatal(err)
			return
		}
	})

	log.Fatal(http.ListenAndServe(":5000", r))
}