fix: add service dimension to metrics (#386)

* fix: add service dimension to metrics

* docs: fix section about service name

docs/advanced-config.md

@@ -69,7 +69,7 @@ The following config options can be set by passing them as arguments to `startTr
 - `signalfx`: A JS object with optional `client` and `dimensions` fields. If you have already setup a [SignalFx client](https://github.com/signalfx/signalfx-nodejs) with custom configuration, you can use this for sending instead of creating, configuring a new one. `dimensions` object adds a pre-defined dimension for each datapoint. The format for `dimensions` is `{key: value, ...}`.
 
    The following is a list of dimensions added by default:
-   - `host`: `os.hostname()`
+   - `service`: see [`serviceName`](#tracing) from the tracing section
    - `metric_source`: `splunk-otel-js`
    - `node_version`: `process.versions.node`, e.g. `16.10.0`
 

src/metrics/index.ts

@@ -17,12 +17,14 @@
 import { context, diag } from '@opentelemetry/api';
 import { suppressTracing } from '@opentelemetry/core';
 import { collectMemoryInfo, MemoryInfo } from './memory';
-import { getEnvBoolean, getEnvNumber } from '../options';
-import * as os from 'os';
+import { defaultServiceName, getEnvBoolean, getEnvNumber } from '../options';
+import { EnvResourceDetector } from '../resource';
+import { SemanticResourceAttributes } from '@opentelemetry/semantic-conventions';
 import * as signalfx from 'signalfx';
 
 interface MetricsOptions {
   enabled: boolean;
+  serviceName: string;
   accessToken: string;
   endpoint: string;
   exportInterval: number;
@@ -281,11 +283,24 @@ export function _setDefaultOptions(
     options.endpoint ||
     process.env.SPLUNK_METRICS_ENDPOINT ||
     'http://localhost:9943';
-  const dimensions = Object.assign(options.signalfx?.dimensions || {}, {
-    host: os.hostname(),
-    metric_source: 'splunk-otel-js',
-    node_version: process.versions.node,
-  });
+
+  const resource = new EnvResourceDetector().detect();
+
+  const serviceName = String(
+    options.serviceName ||
+      process.env.OTEL_SERVICE_NAME ||
+      resource.attributes[SemanticResourceAttributes.SERVICE_NAME] ||
+      defaultServiceName
+  );
+
+  const dimensions = Object.assign(
+    {
+      service: serviceName,
+      metric_source: 'splunk-otel-js',
+      node_version: process.versions.node,
+    },
+    options.signalfx?.dimensions || {}
+  );
 
   const sfxClient =
     options.signalfx?.client ||
@@ -296,6 +311,7 @@ export function _setDefaultOptions(
 
   return {
     enabled,
+    serviceName: serviceName,
     accessToken,
     endpoint,
     exportInterval:

src/options.ts

@@ -37,7 +37,7 @@ import {
 import { SplunkBatchSpanProcessor } from './SplunkBatchSpanProcessor';
 import { Resource } from '@opentelemetry/resources';
 
-const defaultServiceName = 'unnamed-node-service';
+export const defaultServiceName = 'unnamed-node-service';
 
 type SpanExporterFactory = (options: Options) => SpanExporter;
 

test/metrics.test.ts

@@ -95,29 +95,39 @@ describe('metrics', () => {
     it('has expected defaults', () => {
       const options = _setDefaultOptions();
       assert.deepEqual(options.enabled, false);
+      assert.deepEqual(options.serviceName, 'unnamed-node-service');
       assert.deepEqual(options.accessToken, '');
       assert.deepEqual(options.endpoint, 'http://localhost:9943');
       assert.deepEqual(options.exportInterval, 5000);
 
       const sfxClient = options.sfxClient;
       assert.deepStrictEqual(sfxClient['globalDimensions'], {
-        host: os.hostname(),
+        service: 'unnamed-node-service',
         metric_source: 'splunk-otel-js',
         node_version: process.versions.node,
       });
     });
 
     it('is possible to set options via env vars', () => {
       process.env.SPLUNK_ACCESS_TOKEN = 'foo';
+      process.env.OTEL_SERVICE_NAME = 'bigmetric';
       process.env.SPLUNK_METRICS_ENABLED = 'true';
       process.env.SPLUNK_METRICS_ENDPOINT = 'http://localhost:9999';
       process.env.SPLUNK_METRICS_EXPORT_INTERVAL = '1000';
 
       const options = _setDefaultOptions();
       assert.deepEqual(options.enabled, true);
+      assert.deepEqual(options.serviceName, 'bigmetric');
       assert.deepEqual(options.accessToken, 'foo');
       assert.deepEqual(options.endpoint, 'http://localhost:9999');
       assert.deepEqual(options.exportInterval, 1000);
+
+      const sfxClient = options.sfxClient;
+      assert.deepStrictEqual(sfxClient['globalDimensions'], {
+        service: 'bigmetric',
+        metric_source: 'splunk-otel-js',
+        node_version: process.versions.node,
+      });
     });
   });