refactor: rewrite in Go

NOTE: docker not working anymore

main.go

@@ -0,0 +1,93 @@
+package main
+
+import (
+	_ "embed"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"math/rand"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+)
+
+//go:embed public/index.html
+var indexSrc string
+
+const PORT = 3000
+const CACHE_TTL = 5 * time.Minute
+const STORAGE_URL = "https://storage.bunnycdn.com/lilou-cat/"
+const CDN_URL = "https://lilou-cat.b-cdn.net/"
+
+type Image struct {
+	ObjectName string
+}
+
+var (
+	cachedImages    []string
+	cacheExpiration time.Time
+)
+
+func list_images() []string {
+	if time.Now().Before(cacheExpiration) {
+		return cachedImages
+	}
+
+	req, _ := http.NewRequest("GET", STORAGE_URL, nil)
+
+	req.Header.Add("Accept", "application/json")
+	req.Header.Add("AccessKey", os.Getenv("API_KEY"))
+
+	res, err := http.DefaultClient.Do(req)
+	if err != nil {
+		fmt.Printf("error: %s\n", err)
+		return []string{}
+	}
+
+	var images = []Image{}
+
+	err = json.NewDecoder(res.Body).Decode(&images)
+	defer res.Body.Close()
+	if err != nil {
+		fmt.Printf("error: %s\n", err)
+		return []string{}
+	}
+
+	var imageUrls = []string{}
+	for _, image := range images {
+		imageUrls = append(imageUrls, fmt.Sprintf("%s/%s", CDN_URL, image.ObjectName))
+	}
+
+	cachedImages = imageUrls
+	cacheExpiration = time.Now().Add(CACHE_TTL)
+
+	return imageUrls
+}
+
+func getPage(w http.ResponseWriter, r *http.Request) {
+	var images = list_images()
+	var image = images[rand.Intn(len(images))]
+	src := strings.Replace(indexSrc, "{{ IMAGE_URL }}", image, 1)
+
+	io.WriteString(w, src)
+}
+
+func getFavicon(w http.ResponseWriter, r *http.Request) {
+	http.ServeFile(w, r, "public/favicon.ico")
+}
+
+func main() {
+	http.HandleFunc("/", getPage)
+	http.HandleFunc("/favicon.ico", getFavicon)
+
+	err := http.ListenAndServe(fmt.Sprintf(":%d", PORT), nil)
+	fmt.Printf("listening on port %d\n", PORT)
+	if errors.Is(err, http.ErrServerClosed) {
+		fmt.Printf("server closed\n")
+	} else if err != nil {
+		fmt.Printf("error starting server: %s\n", err)
+		os.Exit(1)
+	}
+}