Move supportedLevels out of Validate method

exporter/loggingexporter/config.go

@@ -24,6 +24,16 @@ import (
 	"go.opentelemetry.io/collector/confmap"
 )
 
+var (
+	// supportedLevels in this exporter's configuration.
+	// configtelemetry.LevelNone and other future values are not supported.
+	supportedLevels map[configtelemetry.Level]struct{} = map[configtelemetry.Level]struct{}{
+		configtelemetry.LevelBasic:    {},
+		configtelemetry.LevelNormal:   {},
+		configtelemetry.LevelDetailed: {},
+	}
+)
+
 // Config defines configuration for logging exporter.
 type Config struct {
 	config.ExporterSettings `mapstructure:",squash"` // squash ensures fields are correctly decoded in embedded struct
@@ -89,14 +99,6 @@ func (cfg *Config) Unmarshal(conf *confmap.Conf) error {
 
 // Validate checks if the exporter configuration is valid
 func (cfg *Config) Validate() error {
-	// Supported configtelemetry.Level values for this exporter.
-	// configtelemetry.LevelNone and future values are not supported.
-	supportedLevels := map[configtelemetry.Level]struct{}{
-		configtelemetry.LevelBasic:    {},
-		configtelemetry.LevelNormal:   {},
-		configtelemetry.LevelDetailed: {},
-	}
-
 	if _, ok := supportedLevels[cfg.Verbosity]; !ok {
 		return fmt.Errorf("verbosity level %q is not supported", cfg.Verbosity)
 	}