Fix some error logging - Msg() needs to be called for exiting with exit 1

README.md

@@ -17,6 +17,8 @@ Execute `mullvad-best-server`. It outputs the code, e.g. `de05`. You can then co
 Usage of dist/mullvad-best-server_darwin_amd64/mullvad-best-server:
 -c string
   Server country code, e.g. ch for Switzerland (default "ch")
+-l string
+  Log level. Allowed values: trace, debug, info, warn, error, fatal, panic (default "info")
 -o string
   Output format. 'json' outputs server json
 -t string
@@ -28,7 +30,7 @@ The `-c` flag allows to give a country code. Else `ch` will be used.
 
 
 ## Background
-The program uses `https://api.mullvad.net/www/relays/<SERVER_TYPE/` to get the current server list, pings the ones with the right country
+The program uses `https://api.mullvad.net/www/relays/<SERVER_TYPE>/` to get the current server list, pings the ones with the right country
 and outputs the server with the lowest ping.
 
 ## Integration into a script

main.go

@@ -29,6 +29,9 @@ func main() {
 	zerolog.SetGlobalLevel(level)
 	servers := getServers(*typeFlag)
 	bestIndex := selectBestServerIndex(servers, *countryFlag)
+	if bestIndex == -1 {
+		log.Fatal().Str("country", *countryFlag).Msg("No servers for country found.")
+	}
 	best := servers[bestIndex]
 	log.Debug().Interface("server", best).Msg("Best latency server found.")
 	hostname := strings.TrimSuffix(best.Hostname, "-wireguard")
@@ -37,7 +40,7 @@ func main() {
 	} else {
 		serverJson, err := json.Marshal(best)
 		if err != nil {
-			log.Fatal().Err(err)
+			log.Fatal().Err(err).Msg("Couldn't marshal server information to Json")
 		}
 		fmt.Println(string(serverJson))
 	}
@@ -63,7 +66,7 @@ func selectBestServerIndex(servers []server, country string) int {
 func getServers(serverType string) []server {
 	resp, err := http.Get("https://api.mullvad.net/www/relays/" + serverType + "/")
 	if err != nil {
-		log.Fatal().Err(err)
+		log.Fatal().Err(err).Msg("Couldn't retrieve servers")
 	}
 	responseBody, err := ioutil.ReadAll(resp.Body)
 	defer func(Body io.ReadCloser) {
@@ -78,7 +81,7 @@ func getServers(serverType string) []server {
 	var servers []server
 	err = json.Unmarshal(responseBody, &servers)
 	if err != nil {
-		log.Fatal().Err(err)
+		log.Fatal().Err(err).Msg("couldn't unmarshall server json")
 	}
 	return servers
 }