fix: service.name Resource attribute

Since the 0.20.0 release and the pull request #2227 it seems that serviceName is deprecated and we should use service.name instead. I havn't easily found this information in the changelog, it did require some digging to understand why the service name was now a very long unknown_service:/path/to/node. Documentation says use service.name Resource attribute instead. but it wasn't about replacing serviceName: 'yourServiceName' by service: { name: 'yourServiceName'}.

Author: OmkarKirpan

examples/grpc-js/tracer.js

@@ -7,11 +7,17 @@ const { SimpleSpanProcessor } = require('@opentelemetry/tracing');
 const { JaegerExporter } = require('@opentelemetry/exporter-jaeger');
 const { ZipkinExporter } = require('@opentelemetry/exporter-zipkin');
 const { GrpcInstrumentation } = require('@opentelemetry/instrumentation-grpc');
+const { ResourceAttributes } = require("@opentelemetry/semantic-conventions");
+const { Resource } = require("@opentelemetry/resources");
 
 const EXPORTER = process.env.EXPORTER || '';
 
 module.exports = (serviceName) => {
-  const provider = new NodeTracerProvider();
+  const provider = new NodeTracerProvider({
+    resource: new Resource({
+      [ResourceAttributes.SERVICE_NAME]: serviceName,
+    }),
+  });
 
   let exporter;
   if (EXPORTER.toLowerCase().startsWith('z')) {