main.go

package main

import (
	"errors"
	"fmt"
	"github.com/go-chi/chi"
	"log"
	"net/http"
	"os"
	"strconv"
)

var port = os.Getenv("PORT")

type server struct {
	router *chi.Mux
}

func main() {
	if port == "" {
		port = "5000"
	}

	if err := checkPort(port); err != nil {
		log.Fatalln(err)
	}

	r := chi.NewRouter()
	s := server{router: r}

	address := fmt.Sprintf(":%s", port)
	log.Printf("listening on %s\n", address)
	if err := http.ListenAndServe(address, s.router); err != nil {
		log.Fatalln(err)
	}
}

func (s *server) healthz() http.HandlerFunc {
	return func(resp http.ResponseWriter, req *http.Request) {
		resp.Header().Set("content-type", "text/plain")

		if _, err := resp.Write([]byte("OK")); err != nil {
			fmt.Println(err)
		}
	}
}

func (s *server) putEntry() http.HandlerFunc {
	return nil
}

func (s *server) getEntry() http.HandlerFunc {
	return nil
}

func (s *server) getMap() http.HandlerFunc {
	return nil
}

func (s *server) deleteEntry() http.HandlerFunc {
	return nil
}

func (s *server) installRoutes() {
	s.router.Get("/healthz", s.healthz())

	s.router.Route("/maps/{mapName}", func(r chi.Router) {
		r.Get("/", s.getMap())
		r.Post("/", s.putEntry())
		r.Route("/{key}", func(r chi.Router) {
			r.Get("/", s.getEntry())
			r.Put("/", s.putEntry())
			r.Delete("/", s.deleteEntry())
		})
	})
}

func checkPort(port string) error {
	p, err := strconv.Atoi(port)
	if err != nil {
		return err
	}

	if p < 0 || p > 65535 {
		return errors.New("PORT is out of acceptable range [0..65535]")
	}

	return nil
}