crapcode

main.go

@@ -22,18 +22,17 @@ import (
 )
 
 const (
-	defaultListen  = "0.0.0.0:3333"
+	defaultListen  = ":3333"
 	defaultDir     = "./images"
-	defaultWidth   = 30
+	defaultWidth   = 80
 	cacheSuffixFmt = ".ansi.%d.txt"
 	allowedUA      = "curl"
 	maxImageDim    = 2000
-	redirectURL    = "https://example.com" 
-
 )
 
 var (
 	imgDir      string
+	redirectURL string
 	cacheLock   sync.RWMutex
 	cachedPaths []string
 )
@@ -42,6 +41,7 @@ func main() {
 	rand.Seed(time.Now().UnixNano())
 
 	imgDir = getenv("IMAGES_DIR", defaultDir)
+	redirectURL = getenv("REDIRECT_URL", "https://example.com")
 	listen := getenv("LISTEN", defaultListen)
 
 	if err := os.MkdirAll(imgDir, 0755); err != nil {
@@ -55,7 +55,7 @@ func main() {
 
 	http.HandleFunc("/", rootHandler)
 
-	log.Printf("listening on %s — only curl clients accepted", listen)
+	log.Printf("listening on %s — only curl clients accepted; non-curl will be redirected to %s", listen, redirectURL)
 	if err := http.ListenAndServe(listen, nil); err != nil {
 		log.Fatalf("server failed: %v", err)
 	}
@@ -71,10 +71,8 @@ func getenv(k, fallback string) string {
 
 func rootHandler(w http.ResponseWriter, r *http.Request) {
 	ua := strings.ToLower(r.Header.Get("User-Agent"))
-
 	if !strings.Contains(ua, allowedUA) {
-		http.Redirect(w, r, redirectURL, http.StatusFound) 
-
+		http.Redirect(w, r, redirectURL, http.StatusFound)
 		return
 	}
 
@@ -127,7 +125,9 @@ func rootHandler(w http.ResponseWriter, r *http.Request) {
 
 	w.Header().Set("Content-Type", "text/plain; charset=utf-8")
 	w.WriteHeader(http.StatusOK)
-	io.Copy(w, f)
+	if _, err := io.Copy(w, f); err != nil {
+		log.Printf("write error: %v", err)
+	}
 }
 
 func listImageFiles() []string {
@@ -141,7 +141,6 @@ func listImageFiles() []string {
 		case ".jpg", ".jpeg", ".png", ".gif", ".bmp":
 			files = append(files, path)
 		default:
-
 		}
 		return nil
 	})