feat(config): automatically enable otel if OTEL_EXPORTER_OTLP_ENDPOINT env var is set

Co-authored-by: tronghn <trong.huu.nguyen@nav.no>

pkg/config/config.go

@@ -112,6 +112,7 @@ func Initialize() (*Config, error) {
 	resolveOpenIdProvider()
 	resolveUpstream()
 	resolveVersion()
+	resolveOtel()
 
 	cfg := new(Config)
 	if err := viper.UnmarshalExact(cfg, func(dc *mapstructure.DecoderConfig) {

pkg/config/otel.go

@@ -1,7 +1,10 @@
 package config
 
 import (
+	"os"
+
 	flag "github.com/spf13/pflag"
+	"github.com/spf13/viper"
 )
 
 type OpenTelemetry struct {
@@ -15,7 +18,14 @@ const (
 )
 
 func otelFlags() {
-	// TODO: automatically enable if OTEL_EXPORTER_OTLP_ENDPOINT env var is set
 	flag.Bool(OpenTelemetryEnabled, false, "Enable OpenTelemetry tracing.")
 	flag.String(OpenTelemetryServiceName, "wonderwall", "Service name to use for OpenTelemetry.")
 }
+
+func resolveOtel() {
+	otelEndpoint := os.Getenv("OTEL_EXPORTER_OTLP_ENDPOINT")
+	if otelEndpoint != "" {
+		logger.Infof("config: OTLP endpoint set to %q, enabling OpenTelemetry", otelEndpoint)
+		viper.Set(OpenTelemetryEnabled, "true")
+	}
+}