fix: prefer resource information loaded by env detector

signalfx · Jun 7, 2021 · 52edeaa · 52edeaa
1 parent 2540402
commit 52edeaa
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Showing 2 changed files with 30 additions and 5 deletions.
diff --git a/src/options.ts b/src/options.ts
@@ -88,12 +88,11 @@ export function _setDefaultOptions(options: Partial<Options> = {}): Options {
     options.endpoint || env.OTEL_EXPORTER_JAEGER_ENDPOINT || defaultEndpoint;
 
   const extraTracerConfig = options.tracerConfig || {};
+
   const tracerConfig = {
-    resource: new EnvResourceDetector().detect().merge(
-      new Resource({
-        [ResourceAttributes.SERVICE_NAME]: options.serviceName,
-      })
-    ),
+    resource: configureResource({
+      serviceName: options.serviceName,
+    }),
     ...extraTracerConfig,
   };
 
@@ -169,3 +168,17 @@ function getEnvBoolean(key: string, defaultValue = true) {
 
   return true;
 }
+
+function configureResource(options: { serviceName: string }): Resource {
+  const resource = new EnvResourceDetector().detect();
+
+  if (resource.attributes[ResourceAttributes.SERVICE_NAME] !== undefined) {
+    return resource;
+  }
+
+  return resource.merge(
+    new Resource({
+      [ResourceAttributes.SERVICE_NAME]: options.serviceName,
+    })
+  );
+}
diff --git a/test/options.test.ts b/test/options.test.ts
@@ -104,6 +104,18 @@ describe('options', () => {
       propagatorFactory: testPropagatorFactory,
     });
   });
+
+  it('prefers resource information loaded from the environment', () => {
+    process.env.OTEL_RESOURCE_ATTRIBUTES = 'service.name=foobar';
+    const options = _setDefaultOptions();
+    delete process.env.OTEL_RESOURCE_ATTRIBUTES;
+
+    assert.deepStrictEqual(options.tracerConfig, {
+      resource: new Resource({
+        [ResourceAttributes.SERVICE_NAME]: 'foobar',
+      }),
+    });
+  });
 });
 
 class TestInstrumentation extends InstrumentationBase {