Support b3 (zipkin) OpenTelemetry trace propagation headers (#28)

CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog
 
+## 4.5.0
+- Support [b3](https://github.com/open-telemetry/opentelemetry-js/tree/main/packages/opentelemetry-propagator-b3#b3-formats) (zipkin) OpenTelemetry trace propagation headers ([#28](https://github.com/hasura/ndc-sdk-typescript/pull/28))
+
 ## 4.4.0
 - Updated to support [v0.1.2 of the NDC Spec](https://hasura.github.io/ndc-spec/specification/changelog.html#012)
   - More precise [type representations](https://hasura.github.io/ndc-spec/specification/schema/scalar-types.html#type-representations) of scalar types were added and the general numeric ones were deprecated (`number` and `integer`)

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@hasura/ndc-sdk-typescript",
-  "version": "4.4.0",
+  "version": "4.5.0",
   "description": "",
   "main": "./dist/index.js",
   "types": "./dist/index.d.ts",

src/instrumentation.ts

@@ -7,6 +7,8 @@ import { FastifyInstrumentation } from "@opentelemetry/instrumentation-fastify";
 import { HttpInstrumentation } from "@opentelemetry/instrumentation-http";
 import { FetchInstrumentation } from "@opentelemetry/instrumentation-fetch";
 import { Attributes, Span, SpanStatusCode, Tracer } from "@opentelemetry/api";
+import { CompositePropagator, W3CBaggagePropagator, W3CTraceContextPropagator } from "@opentelemetry/core";
+import { B3Propagator, B3InjectEncoding } from "@opentelemetry/propagator-b3"
 
 let sdk: opentelemetry.NodeSDK | null = null;
 
@@ -52,9 +54,21 @@ export function initTelemetry(
       new PinoInstrumentation({
         logHook: (span, record, level) => {
           record["resource.service.name"] = serviceName;
+          // This logs the parent span ID in the pino logs, useful for debugging propagation.
+          // parentSpanId is an internal property, hence the cast to any, because I can't
+          // seem to find a way to get at it through a supported API 😭
+          record["parent_span_id"] = (span as any).parentSpanId;
         },
       }),
     ],
+    textMapPropagator: new CompositePropagator({
+      propagators: [
+        new W3CTraceContextPropagator(),
+        new W3CBaggagePropagator(),
+        new B3Propagator(),
+        new B3Propagator({ injectEncoding: B3InjectEncoding.MULTI_HEADER }),
+      ]
+    }),
   });
 
   process.on("beforeExit", async () => {

src/server.ts

@@ -176,7 +176,7 @@ export async function startServer<Configuration, State>(
         Body: QueryRequest;
       }>
     ) => {
-      request.log.debug({ requestBody: request.body }, "Query Request");
+      request.log.debug({ requestHeaders: request.headers, requestBody: request.body }, "Query Request");
 
       const queryResponse = await withActiveSpan(
         tracer,
@@ -201,7 +201,7 @@ export async function startServer<Configuration, State>(
       },
     },
     async (request: FastifyRequest<{ Body: QueryRequest }>) => {
-      request.log.debug({ requestBody: request.body }, "Explain Request");
+      request.log.debug({ requestHeaders: request.headers, requestBody: request.body }, "Explain Request");
 
       const explainResponse = await withActiveSpan(
         tracer,
@@ -233,7 +233,7 @@ export async function startServer<Configuration, State>(
         Body: MutationRequest;
       }>
     ): Promise<MutationResponse> => {
-      request.log.debug({ requestBody: request.body }, "Mutation Request");
+      request.log.debug({ requestHeaders: request.headers, requestBody: request.body }, "Mutation Request");
 
       const mutationResponse = await withActiveSpan(
         tracer,
@@ -262,7 +262,7 @@ export async function startServer<Configuration, State>(
     },
     async (request: FastifyRequest<{ Body: MutationRequest }>) => {
       request.log.debug(
-        { requestBody: request.body },
+        { requestHeaders: request.headers, requestBody: request.body },
         "Mutation Explain Request"
       );