refactor(exporter): extract function to create traces exporter

Issue #3412

Author: atsu85

autoinstrumentation/nodejs/src/autoinstrumentation.ts

@@ -1,5 +1,5 @@
 import { getNodeAutoInstrumentations } from '@opentelemetry/auto-instrumentations-node';
-import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-grpc';
+import { OTLPTraceExporter as OTLPGrpcTraceExporter } from '@opentelemetry/exporter-trace-otlp-grpc';
 import { OTLPMetricExporter } from '@opentelemetry/exporter-metrics-otlp-grpc';
 import { PrometheusExporter } from '@opentelemetry/exporter-prometheus';
 import { PeriodicExportingMetricReader } from '@opentelemetry/sdk-metrics';
@@ -12,6 +12,10 @@ import { diag } from '@opentelemetry/api';
 
 import { NodeSDK } from '@opentelemetry/sdk-node';
 
+function getTraceExporter() {
+            return new OTLPGrpcTraceExporter();
+}
+
 function getMetricReader() {
     switch (process.env.OTEL_METRICS_EXPORTER) {
         case undefined:
@@ -35,7 +39,7 @@ function getMetricReader() {
 const sdk = new NodeSDK({
     autoDetectResources: true,
     instrumentations: [getNodeAutoInstrumentations()],
-    traceExporter: new OTLPTraceExporter(),
+    traceExporter: getTraceExporter(),
     metricReader: getMetricReader(),
     resourceDetectors:
         [