remove default endpoint, stub initTracer()

Having a default means each invocation of otel-cli might timeout on
trying to connect over OTLP.

With this change, in the absence of --endpoint or OTEL_EXPORTER_OTLP_ENDPOINT
otel-cli will now not configure opentelemetry-go at all, but the rest of
otel-cli will work as usual, just no spans are sent out.

Signed-off-by: Amy Tobey <atobey@equinix.com>

cmd/plumbing.go

@@ -26,6 +26,13 @@ import (
 func initTracer() (context.Context, func()) {
 	ctx := context.Background()
 
+	// when no endpoint is set, do not set up plumbing. everything will still
+	// run but in non-recording mode, and otel-cli is effectively disabled
+	// and will not time out trying to connect out
+	if otlpEndpoint == "" {
+		return ctx, func() {}
+	}
+
 	grpcOpts := []otlpgrpc.Option{otlpgrpc.WithEndpoint(otlpEndpoint)}
 
 	// gRPC does the right thing and forces us to say WithInsecure to disable encryption,

cmd/root.go

@@ -39,7 +39,7 @@ func addCommonParams(cmd *cobra.Command) {
 	// --config / -c a viper configuration file
 	cmd.Flags().StringVarP(&cfgFile, "config", "c", "", "config file (default is $HOME/.otel-cli.yaml)")
 
-	cmd.Flags().StringVar(&otlpEndpoint, "endpoint", "localhost:4317", "dial address for the desired OTLP/gRPC endpoint")
+	cmd.Flags().StringVar(&otlpEndpoint, "endpoint", "", "dial address for the desired OTLP/gRPC endpoint")
 	viper.BindPFlag("endpoint", rootCmd.Flags().Lookup("endpoint"))
 	viper.BindEnv("OTEL_EXPORTER_OTLP_ENDPOINT", "endpoint")
 }