add tests

Author: serkan-ozal

nodejs/packages/layer/test/wrapper.spec.ts

@@ -1,22 +1,33 @@
 import type { AwsSdkInstrumentationConfig } from '@opentelemetry/instrumentation-aws-sdk';
-import { stub } from 'sinon';
+import { SDKRegistrationConfig } from '@opentelemetry/sdk-trace-base';
+import { TextMapPropagator } from '@opentelemetry/api';
 
 import { wrap, unwrap } from '../src/wrapper';
 
+import { stub } from 'sinon';
+import assert from 'assert';
+
 declare global {
   function configureAwsInstrumentation(
     defaultConfig: AwsSdkInstrumentationConfig,
   ): AwsSdkInstrumentationConfig;
+  function configureSdkRegistration(
+    defaultSdkRegistration: SDKRegistrationConfig,
+  ): SDKRegistrationConfig;
 }
 
-const assert = require('assert');
-
 describe('wrapper', () => {
+  let oldEnv: NodeJS.ProcessEnv;
+
   beforeEach(() => {
+    oldEnv = { ...process.env };
+
     unwrap();
   });
 
   afterEach(() => {
+    process.env = oldEnv;
+
     unwrap();
   });
 
@@ -30,4 +41,64 @@ describe('wrapper', () => {
       assert(configureAwsInstrumentationStub.calledOnce);
     });
   });
+
+  describe('getPropagator', () => {
+    const testConfiguredPropagator = (
+      propagatorNames: string[],
+      expectedPropagatorFields: string[],
+    ) => {
+      if (propagatorNames && propagatorNames.length) {
+        process.env.OTEL_PROPAGATORS = propagatorNames.join(',');
+      }
+
+      const configureSdkRegistrationStub = stub().returnsArg(0);
+      global.configureSdkRegistration = configureSdkRegistrationStub;
+      wrap();
+      assert(configureSdkRegistrationStub.calledOnce);
+
+      const sdkRegistrationConfig: SDKRegistrationConfig =
+        configureSdkRegistrationStub.getCall(0).firstArg;
+      assert.notEqual(sdkRegistrationConfig, null);
+
+      const propagator: TextMapPropagator | null | undefined =
+        sdkRegistrationConfig.propagator;
+      assert.notEqual(propagator, null);
+
+      const actualPropagatorFields: string[] | undefined = propagator?.fields();
+      assert.notEqual(actualPropagatorFields, null);
+      assert.deepEqual(actualPropagatorFields, expectedPropagatorFields);
+    };
+
+    it('is configured by default', () => {
+      // by default, 'W3CTraceContextPropagator' and 'W3CBaggagePropagator' propagators are added.
+      // - 'traceparent' and 'tracestate' fields are used by the 'W3CTraceContextPropagator'
+      // - 'baggage' field is used by the 'W3CBaggagePropagator'
+      testConfiguredPropagator([], ['traceparent', 'tracestate', 'baggage']);
+    });
+
+    it('is configured to w3c-trace-context by env var', () => {
+      // 'traceparent' and 'tracestate' fields are used by the 'W3CTraceContextPropagator'
+      testConfiguredPropagator(['tracecontext'], ['traceparent', 'tracestate']);
+    });
+
+    it('is configured to w3c-baggage by env var', () => {
+      // 'baggage' field is used by the 'W3CBaggagePropagator'
+      testConfiguredPropagator(['baggage'], ['baggage']);
+    });
+
+    it('is configured to xray by env var', () => {
+      // 'x-amzn-trace-id' field is used by the 'AWSXRayPropagator'
+      testConfiguredPropagator(['xray'], ['x-amzn-trace-id']);
+    });
+
+    it('is configured to xray-lambda by env var', () => {
+      // 'x-amzn-trace-id' field is used by the 'AWSXRayLambdaPropagator'
+      testConfiguredPropagator(['xray'], ['x-amzn-trace-id']);
+    });
+
+    it('is configured by unsupported propagator', () => {
+      // in case of unsupported propagator, warning log is printed and empty propagator array is returned
+      testConfiguredPropagator(['jaeger'], []);
+    });
+  });
 });