feat: add no-cache option to disable caching in HTTP responses

main.go

@@ -25,6 +25,7 @@ var (
 	InfoLogger    *log.Logger
 	WarningLogger *log.Logger
 	ErrorLogger   *log.Logger
+	noCacheBool   bool
 	verboseBool   bool
 	baseURLs      []string
 	apiURLs       []string
@@ -51,6 +52,11 @@ func renderJSON(w http.ResponseWriter, req *http.Request) {
 	if verboseBool {
 		DebugLogger.Printf("JSON generation initiated for provider: %s", provider)
 	}
+	if noCacheBool {
+		w.Header().Set("Cache-Control", "no-store, no-cache, must-revalidate, max-age=0")
+		w.Header().Set("Pragma", "no-cache")
+		w.Header().Set("Expires", "0")
+	}
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(http.StatusOK)
 	_, err = w.Write(jsonData)
@@ -76,7 +82,13 @@ func renderPage(w http.ResponseWriter, req *http.Request) {
 		return
 	}
 
+	if noCacheBool {
+		w.Header().Set("Cache-Control", "no-store, no-cache, must-revalidate, max-age=0")
+		w.Header().Set("Pragma", "no-cache")
+		w.Header().Set("Expires", "0")
+	}
 	w.Header().Set("Content-Type", "text/html")
+
 	if verboseBool {
 		DebugLogger.Printf("Serving file: %s", serveFile)
 	}
@@ -136,9 +148,14 @@ func customHandler(w http.ResponseWriter, req *http.Request) {
 	path := req.URL.Path
 	rootPath := []string{"/", "/index.html", "/index.htm"}
 	if slices.Contains(rootPath, path) {
-		// if verboseBool {
-		// 	DebugLogger.Printf("Serving file: %s", path)
-		// }
+		if noCacheBool {
+			w.Header().Set("Cache-Control", "no-store, no-cache, must-revalidate, max-age=0")
+			w.Header().Set("Pragma", "no-cache")
+			w.Header().Set("Expires", "0")
+		}
+		if verboseBool {
+			DebugLogger.Printf("Serving file: %s", path)
+		}
 		http.ServeFile(w, req, filepath.Join(webDir, "index.html"))
 		return
 	}
@@ -197,7 +214,7 @@ func main() {
   - serve ACME HTML pages, trigger Puppet, expose API
 
 Usage:
-  %v [--listen-address=LISTENADDRESS] [--listen-port=LISTENPORT] [--verbose]
+  %v [--listen-address=LISTENADDRESS] [--listen-port=LISTENPORT] [--no-cache] [--verbose]
   %v -h | --help
   %v -b | --build
   %v -v | --version
@@ -206,6 +223,7 @@ Options:
   -h --help                        Show this screen
   -b --build                       Print version and build information and exit
   -v --version                     Print version information and exit
+  --no-cache					   Disable caching
   --listen-address=LISTENADDRESS   Web server address. Check Go net/http documentation [default: any]
   --listen-port=LISTENPORT         Web server port [default: 8000]
   --verbose                        Log also successful connections
@@ -233,6 +251,7 @@ Options:
 
 	baseDir = "/etc"
 	webDir = "/var/www/acme_web"
+	noCacheBool = arguments["--no-cache"].(bool)
 	verboseBool = arguments["--verbose"].(bool)
 	listenAddress := arguments["--listen-address"].(string)
 	listenPort := arguments["--listen-port"].(string)