Merge pull request #29 from nmaggioni/nm_logging_level_from_env_var

Get logging level from environment

README.md

@@ -227,6 +227,9 @@ Command line options
   `Warning`, `Error`, `Fatal` and `Panic`. Default level is `Info` which will
   log anything that is info level or above (warning, error, fatal, panic).
 
+  Logging level can also be set using the `LOGGING_LEVEL` environment variable. The
+  command line option takes precedence over the environment setting.
+
 `-moonraker.apikey <string>`
 
   Set the API Key to authenticate with the Klipper APIs.

klipper-exporter.service

@@ -9,6 +9,7 @@ StartLimitIntervalSec=5
 [Service]
 User=pi
 WorkingDirectory=/home/pi/klipper-exporter
+EnvironmentFile=/home/pi/klipper-exporter/prometheus-klipper-exporter.env
 ExecStart=/home/pi/klipper-exporter/prometheus-klipper-exporter
 Restart=always
 RestartSec=1s

main.go

@@ -63,6 +63,11 @@ func handler(w http.ResponseWriter, r *http.Request) {
 }
 
 func main() {
+
+	if loggingLevelEnv, loggingLevelEnvSet := os.LookupEnv("LOGGING_LEVEL"); loggingLevelEnvSet {
+		*loggingLevel = loggingLevelEnv
+	}
+
 	flag.Parse()
 
 	level, err := log.ParseLevel(strings.ToLower(*loggingLevel))