feat(config): config file is configurable

cmd/salt-exporter/config.go

@@ -13,6 +13,7 @@ import (
 	"github.com/spf13/viper"
 )
 
+const defaultConfigFilename = "config.yml"
 const defaultLogLevel = "info"
 const defaultPort = 2112
 const defaultHealthMinion = true
@@ -48,9 +49,10 @@ type Config struct {
 	Metrics metrics.Config
 }
 
-func parseFlags() bool {
+func parseFlags() (string, bool) {
 	// flags
 	versionCmd := flag.Bool("version", false, "print version")
+	configFile := flag.String("config-file", defaultConfigFilename, "config filepath")
 	flag.String("log-level", defaultLogLevel, "log level (debug, info, warn, error, fatal, panic, disabled)")
 	flag.String("host", "", "listen address")
 	flag.Int("port", defaultPort, "listen port")
@@ -80,7 +82,7 @@ func parseFlags() bool {
 		os.Exit(0)
 	}
 
-	return *healthMinions
+	return *configFile, *healthMinions
 }
 
 func setDefaults(healthMinions bool) {
@@ -117,10 +119,14 @@ func getConfig(configFileName string, healthMinions bool) (Config, error) {
 	}
 
 	// bind configuration file
-	ext := filepath.Ext(configFileName)
-	viper.SetConfigName(strings.TrimSuffix(configFileName, ext))
-	viper.SetConfigType(strings.TrimPrefix(ext, "."))
-	viper.AddConfigPath(".")
+	if filepath.IsAbs(configFileName) {
+		viper.SetConfigFile(configFileName)
+	} else {
+		ext := filepath.Ext(configFileName)
+		viper.SetConfigName(strings.TrimSuffix(configFileName, ext))
+		viper.SetConfigType(strings.TrimPrefix(ext, "."))
+		viper.AddConfigPath(".")
+	}
 
 	viper.SetEnvKeyReplacer(strings.NewReplacer("-", "_", ".", "__"))
 	viper.SetEnvPrefix("SALT")
@@ -155,10 +161,10 @@ func checkRequirements(cfg Config) error {
 	return nil
 }
 
-func ReadConfig(configFileName string) (Config, error) {
+func ReadConfig() (Config, error) {
 	var err error
 
-	healthMinions := parseFlags()
+	configFileName, healthMinions := parseFlags()
 
 	cfg, err := getConfig(configFileName, healthMinions)
 	if err != nil {

cmd/salt-exporter/main.go

@@ -18,8 +18,6 @@ import (
 	"github.com/rs/zerolog/log"
 )
 
-const configFileName = "config.yml"
-
 var (
 	version = "unknown"
 	commit  = "unknown"
@@ -107,7 +105,7 @@ func main() {
 	defer quit()
 	logging.Configure()
 
-	config, err := ReadConfig(configFileName)
+	config, err := ReadConfig()
 	if err != nil {
 		log.Fatal().Err(err).Msg("failed to load settings during initialization") //nolint:gocritic // force exit
 	}

config.yml

@@ -0,0 +1 @@
+listen-port: 3333

docs/docs/salt-exporter/configuration.md

@@ -18,6 +18,8 @@ The salt-exporter can be configured with flags, environments variables and confi
 
 The exporter is looking for `config.yml`.
 
+Note: You can specify a specific config filepath using `--config-file`, i.e. `--config-file="/srv/salt-exporter/config.yml"`
+
 See below a full example of a configuration file:
 
 ```  { .yaml .copy }
@@ -153,18 +155,22 @@ SALT_METRICS__GLOBAL__FILTERS__IGNORE_TEST=true
 
 ```
 ./salt-exporter -help
+  -config-file string
+        config filepath (default "config.yml")
   -health-functions-filter string
         [DEPRECATED] apply filter on functions to monitor, separated by a comma (default "highstate")
-  -health-states-filter string
-        [DEPRECATED] apply filter on states to monitor, separated by a comma (default "highstate")
   -health-minions
         [DEPRECATED] enable minion metrics (default true)
+  -health-states-filter string
+        [DEPRECATED] apply filter on states to monitor, separated by a comma (default "highstate")
   -host string
         listen address
   -ignore-mock
         ignore mock=True events
   -ignore-test
         ignore test=True events
+  -ipc-file string
+        file location of the salt-master event bus (default "/var/run/salt/master/master_event_pub.ipc")
   -log-level string
         log level (debug, info, warn, error, fatal, panic, disabled) (default "info")
   -port int
@@ -175,5 +181,7 @@ SALT_METRICS__GLOBAL__FILTERS__IGNORE_TEST=true
         TLS certificated
   -tls-key string
         TLS private key
+  -version
+        print version
 ```