Add parameter flags

README.md

@@ -5,6 +5,6 @@ Website to show home server infrastructure up/down indicators
 ## Build and run
 
 ```sh
-$ go build main.go
-$ go run main.go
+$ go build main.go functions.go
+$ ./main
 ```

main.go

@@ -1,9 +1,11 @@
 package main
 
 import (
+	"flag"
 	"fmt"
 	"log"
 	"net/http"
+	"os"
 )
 
 type WebsiteStatus struct {
@@ -13,19 +15,88 @@ type WebsiteStatus struct {
 	IconURL     string
 }
 
+type Config struct {
+	Mode            string
+	WebsiteConfFile string
+	ListenAddress   string
+	Port            int
+	Verbose         bool
+}
+
+var config Config
+
 func main() {
-	websites, err := readWebsitesFromFile("websites.conf")
+	config = parseFlags()
+
+	if config.Verbose {
+		fmt.Printf("Reading websites from file %s", config.WebsiteConfFile)
+	}
+
+	websites, err := readWebsitesFromFile(config.WebsiteConfFile)
+
 	if err != nil {
 		log.Fatal(err)
 	}
 
+	runWebsite(fmt.Sprintf("%s:%d", config.ListenAddress, config.Port), websites)
+}
+
+func parseFlags() Config {
+	// Define command-line flags
+	websiteConfFileFlag := flag.String("config", "websites.conf", "Path to the config file")
+	verboseFlag := flag.Bool("verbose", false, "Enable verbose mode")
+	listenAddressFlag := flag.String("address", "localhost", "The address the server will listen on")
+	portFlag := flag.Int("port", 8080, "The port the server will listen on")
+	modeFlag := flag.String("mode", "server", "The mode the program will run in. Options are \"cmd\" and \"server\"")
+
+	// Parse command-line flags
+	flag.Parse()
+
+	// Access the parsed values
+	config := Config{
+		WebsiteConfFile: *websiteConfFileFlag,
+		Verbose:         *verboseFlag,
+		ListenAddress:   *listenAddressFlag,
+		Port:            *portFlag,
+		Mode:            *modeFlag,
+	}
+
+	success := true
+
+	// Check if the config file exists
+	if _, err := os.Stat(config.WebsiteConfFile); os.IsNotExist(err) {
+		success = false
+		fmt.Printf("File '%s' does not exist\n", config.WebsiteConfFile)
+	}
+
+	if config.Port < 0 || config.Port > 65535 {
+		success = false
+		fmt.Printf("Port '%d' is out of range for a port, must be between 0 and 65535\n", config.Port)
+	}
+
+	if config.Mode != "cmd" && config.Mode != "server" {
+		success = false
+		fmt.Printf("Mode has to be either cmd or server, but was '%s'\n", config.Mode)
+	}
+
+	if !success {
+		fmt.Printf("Config error(s), aborting...\n")
+		os.Exit(1)
+	}
+
+	return config
+}
+
+func runWebsite(url string, websites []WebsiteStatus) {
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 		renderTemplate(w, websites)
 	})
 	http.HandleFunc("/check", handleCheck)
 	http.Handle("/static/", http.StripPrefix("/static/", http.FileServer(http.Dir("static"))))
 
-	fmt.Println("Server listening on http://localhost:8080")
-
-	log.Fatal(http.ListenAndServe(":8080", nil))
+	if config.Verbose {
+		fmt.Println("Server listening on ", url)
+	}
+
+	log.Fatal(http.ListenAndServe(url, nil))
 }