From 6b6cd4b60881a3e74363ac8a6b9c86b1331f68b1 Mon Sep 17 00:00:00 2001
From: Jamie King <jamie.king@aexp.com>
Date: Mon, 1 Apr 2024 12:37:09 -0700
Subject: [PATCH] feat(tracing): include B3 propagator (#1352)

---
 __tests__/integration/one-app.spec.js         | 20 ++++++++++---
 __tests__/server/utils/tracer.spec.js         | 28 +++++++++++++++++--
 package-lock.json                             |  1 +
 package.json                                  |  1 +
 prod-sample/api/server.js                     |  3 ++
 .../0.0.0/src/components/SsrFrank.jsx         |  9 +++---
 src/server/utils/tracer.js                    | 16 +++++++++--
 7 files changed, 66 insertions(+), 12 deletions(-)

diff --git a/__tests__/integration/one-app.spec.js b/__tests__/integration/one-app.spec.js
index c1533b812..c321da486 100644
--- a/__tests__/integration/one-app.spec.js
+++ b/__tests__/integration/one-app.spec.js
@@ -951,6 +951,7 @@ describe('Tests that require Docker setup', () => {
         ...defaultFetchOptions,
       });
       const htmlData = await response.text();
+      const traceId = response.headers.get('traceid');
       const scriptContents = htmlData.match(
         /<script id="initial-state" nonce=\S+>([^<]+)<\/script>/
       )[1];
@@ -965,7 +966,10 @@ describe('Tests that require Docker setup', () => {
           },
         ],
         secretMessage: 'you are being watched',
-        traceparent: expect.any(String),
+        traceparent: expect.stringContaining(traceId),
+        xB3TraceId: traceId,
+        xB3TraceSpan: expect.any(String),
+        xB3Sampled: expect.any(String),
         loadedOnServer: true,
       });
     });
@@ -1318,7 +1322,9 @@ describe('Tests that require Docker setup', () => {
       )[1];
       const initialState = scriptContents.match(/window\.__INITIAL_STATE__ = "([^<]+)";/)[1];
       const state = transit.fromJSON(initialState.replace(/\\/g, ''));
-      const { traceparent } = state.getIn(['modules', 'ssr-frank', 'data']);
+      const {
+        traceparent, xB3TraceId, xB3TraceSpan, xB3Sampled,
+      } = state.getIn(['modules', 'ssr-frank', 'data']);
 
       const resourceAttributes = trace.resourceSpans[0].resource.attributes.reduce(
         (acc, attribute) => ({
@@ -1403,8 +1409,8 @@ describe('Tests that require Docker setup', () => {
       });
 
       expect(response.headers.get('traceid')).toBe(traceId);
-      expect(traceparent).toEqual(expect.stringContaining(traceId));
-
+      expect(xB3TraceId).toBe(traceId);
+      expect(traceparent).toBe(`00-${xB3TraceId}-${xB3TraceSpan}-0${xB3Sampled}`);
       const httpSpans = getSpans('@opentelemetry/instrumentation-http', traceId);
       expect(httpSpans.length).toBe(2);
       const spans = getSpans('@autotelic/fastify-opentelemetry', traceId);
@@ -1811,6 +1817,9 @@ describe('Tests that can run against either local Docker setup or remote One App
               posts: [{ id: 1, title: 'json-server', author: 'typicode' }],
               secretMessage: null,
               traceparent: null,
+              xB3TraceId: null,
+              xB3TraceSpan: null,
+              xB3Sampled: null,
               loadedOnServer: false,
             },
           });
@@ -1835,6 +1844,9 @@ describe('Tests that can run against either local Docker setup or remote One App
               posts: [{ id: 1, title: 'json-server', author: 'typicode' }],
               secretMessage: null,
               traceparent: null,
+              xB3TraceId: null,
+              xB3TraceSpan: null,
+              xB3Sampled: null,
               loadedOnServer: false,
             },
           });
diff --git a/__tests__/server/utils/tracer.spec.js b/__tests__/server/utils/tracer.spec.js
index be126b734..1e4401515 100644
--- a/__tests__/server/utils/tracer.spec.js
+++ b/__tests__/server/utils/tracer.spec.js
@@ -27,10 +27,18 @@ import {
   ConsoleSpanExporter,
   NoopSpanProcessor,
 } from '@opentelemetry/sdk-trace-base';
-import { W3CTraceContextPropagator } from '@opentelemetry/core';
+import {
+  CompositePropagator,
+  W3CTraceContextPropagator,
+} from '@opentelemetry/core';
+import {
+  B3Propagator,
+  B3InjectEncoding,
+} from '@opentelemetry/propagator-b3';
 import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-grpc';
 
 jest.mock('@opentelemetry/core');
+jest.mock('@opentelemetry/propagator-b3');
 jest.mock('@opentelemetry/instrumentation');
 jest.mock('@opentelemetry/instrumentation-http');
 jest.mock('@opentelemetry/instrumentation-pino');
@@ -132,10 +140,26 @@ describe('tracer', () => {
       tracerProvider: _tracerProvider,
       instrumentations: [expect.any(HttpInstrumentation), expect.any(PinoInstrumentation)],
     });
+  });
+
+  it('should configure the propagator', () => {
+    const { _tracerProvider } = setup({});
     expect(_tracerProvider.register).toHaveBeenCalledTimes(1);
     expect(_tracerProvider.register).toHaveBeenCalledWith(expect.objectContaining({
-      propagator: expect.any(W3CTraceContextPropagator),
+      propagator: expect.any(CompositePropagator),
     }));
+    expect(CompositePropagator).toHaveBeenCalledTimes(1);
+    expect(CompositePropagator).toHaveBeenCalledWith({
+      propagators: [
+        expect.any(B3Propagator),
+        expect.any(W3CTraceContextPropagator),
+      ],
+    });
+    expect(W3CTraceContextPropagator).toHaveBeenCalledTimes(1);
+    expect(B3Propagator).toHaveBeenCalledTimes(1);
+    expect(B3Propagator).toHaveBeenCalledWith({
+      injectEncoding: B3InjectEncoding.MULTI_HEADER,
+    });
   });
 
   it('should not trace outgoing requests that do not have a parent span', () => {
diff --git a/package-lock.json b/package-lock.json
index f5b0fc40e..98a46ecdb 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -32,6 +32,7 @@
         "@opentelemetry/instrumentation": "^0.49.1",
         "@opentelemetry/instrumentation-http": "^0.49.1",
         "@opentelemetry/instrumentation-pino": "^0.36.0",
+        "@opentelemetry/propagator-b3": "^1.22.0",
         "@opentelemetry/resources": "^1.22.0",
         "@opentelemetry/sdk-trace-base": "^1.22.0",
         "@opentelemetry/sdk-trace-node": "^1.22.0",
diff --git a/package.json b/package.json
index bb1b81920..8bef38361 100644
--- a/package.json
+++ b/package.json
@@ -102,6 +102,7 @@
     "@opentelemetry/instrumentation": "^0.49.1",
     "@opentelemetry/instrumentation-http": "^0.49.1",
     "@opentelemetry/instrumentation-pino": "^0.36.0",
+    "@opentelemetry/propagator-b3": "^1.22.0",
     "@opentelemetry/resources": "^1.22.0",
     "@opentelemetry/sdk-trace-base": "^1.22.0",
     "@opentelemetry/sdk-trace-node": "^1.22.0",
diff --git a/prod-sample/api/server.js b/prod-sample/api/server.js
index 511c82263..258549619 100644
--- a/prod-sample/api/server.js
+++ b/prod-sample/api/server.js
@@ -39,6 +39,9 @@ server.use((req, res, next) => {
   const secretMessage = req.headers['auth-token'] ? 'you are being watched' : 'unauthorised';
   res.append('secret-message', secretMessage);
   res.append('traceparent', req.headers.traceparent);
+  res.append('x-b3-traceid', req.headers['x-b3-traceid']);
+  res.append('x-b3-spanid', req.headers['x-b3-spanid']);
+  res.append('x-b3-sampled', req.headers['x-b3-sampled']);
   next();
 });
 server.use(router);
diff --git a/prod-sample/sample-modules/ssr-frank/0.0.0/src/components/SsrFrank.jsx b/prod-sample/sample-modules/ssr-frank/0.0.0/src/components/SsrFrank.jsx
index ffc2259bd..63f9f7ba2 100644
--- a/prod-sample/sample-modules/ssr-frank/0.0.0/src/components/SsrFrank.jsx
+++ b/prod-sample/sample-modules/ssr-frank/0.0.0/src/components/SsrFrank.jsx
@@ -33,15 +33,16 @@ const loadModuleData = async ({ store, fetchClient }) => {
   }
   store.dispatch({ type: FAKE_REQUEST });
   const fastRes = await fetchClient('https://fast.api.frank/posts');
-  const secretMessage = fastRes.headers.get('secret-message');
-  const traceparent = fastRes.headers.get('traceparent');
   const posts = await fastRes.json();
   store.dispatch({
     type: FAKE_SUCCESS,
     data: {
       posts,
-      secretMessage,
-      traceparent,
+      secretMessage: fastRes.headers.get('secret-message'),
+      traceparent: fastRes.headers.get('traceparent'),
+      xB3TraceId: fastRes.headers.get('x-b3-traceid'),
+      xB3TraceSpan: fastRes.headers.get('x-b3-spanid'),
+      xB3Sampled: fastRes.headers.get('x-b3-sampled'),
       loadedOnServer: !global.BROWSER,
     },
   });
diff --git a/src/server/utils/tracer.js b/src/server/utils/tracer.js
index dcd466f75..141e6a155 100644
--- a/src/server/utils/tracer.js
+++ b/src/server/utils/tracer.js
@@ -27,7 +27,14 @@ import {
   NoopSpanProcessor,
 } from '@opentelemetry/sdk-trace-base';
 import { trace } from '@opentelemetry/api';
-import { W3CTraceContextPropagator } from '@opentelemetry/core';
+import {
+  CompositePropagator,
+  W3CTraceContextPropagator,
+} from '@opentelemetry/core';
+import {
+  B3Propagator,
+  B3InjectEncoding,
+} from '@opentelemetry/propagator-b3';
 import { OTLPTraceExporter } from '@opentelemetry/exporter-trace-otlp-grpc';
 import {
   Resource,
@@ -107,7 +114,12 @@ if (process.env.NODE_ENV === 'development' && argv.logLevel === 'trace') {
 }
 
 tracerProvider.register({
-  propagator: new W3CTraceContextPropagator(),
+  propagator: new CompositePropagator({
+    propagators: [
+      new B3Propagator({ injectEncoding: B3InjectEncoding.MULTI_HEADER }),
+      new W3CTraceContextPropagator(),
+    ],
+  }),
 });
 
 ['SIGINT', 'SIGTERM'].forEach((signalName) => process.on(signalName, async () => {