Fix missing headers for fetch (#687)

* fix: test typo

* attempt to fix #679

* export enableCapture

* fix type

* fix type for undici

* edits to package-lock.json(s)

---------

Co-authored-by: jjllee <[email protected]>

sdk_contrib/fetch/README.md

@@ -43,3 +43,4 @@ I could find that this will happen, but throwing it out there "just in case".
 ## Contributors
 
 - [Jason Terando](https://github.com/jasonterando)
+- [Bernd Fuhrmann](https://github.com/berndfuhrmann)

sdk_contrib/fetch/lib/fetch_p.d.ts

@@ -17,3 +17,9 @@ export function captureFetchModule(
   subsegmentCallback?: (subsegment: AWSXRay.Subsegment, req: fetchModule.Request, res: fetchModule.Response | null, error?: Error | undefined) => void):
   (url: URL | fetchModule.RequestInfo, init?: fetchModule.RequestInit | undefined) => Promise<fetchModule.Response>;
 
+export function enableCapture<Fetch, Request>(
+  fetch: Fetch,
+  request: Request,
+  downstreamXRayEnabled?: boolean,
+  subsegmentCallback?: (subsegment: AWSXRay.Subsegment, req: Request, res: Response | null, error?: Error | undefined) => void
+): Fetch;

sdk_contrib/fetch/lib/fetch_p.js

@@ -54,7 +54,18 @@ function captureFetchModule(module, downstreamXRayEnabled, subsegmentCallback) {
   return module.default;
 }
 
-const enableCapture = function enableCapture(baseFetchFunction, requestClass, downstreamXRayEnabled, subsegmentCallback) {
+/**
+ * Return a fetch function that will pass segment information to the target host.
+ * This does not change any globals
+ * @param {function} baseFetchFunction fetch function to use as basis
+ * @param {function} requestClass Request class to use. This should correspond to the supplied fetch function.
+ * @param {boolean} downstreamXRayEnabled - when true, adds a "traced:true" property to the subsegment
+ *   so the AWS X-Ray service expects a corresponding segment from the downstream service.
+ * @param {function} subsegmentCallback - a callback that is called with the subsegment, the fetch request,
+ *   the fetch response and any error issued, allowing custom annotations and metadata to be added.
+ * @returns Response
+ */
+function enableCapture(baseFetchFunction, requestClass, downstreamXRayEnabled, subsegmentCallback) {
 
   const overridenFetchAsync = async (...args) => {
     const thisDownstreamXRayEnabled = !!downstreamXRayEnabled;
@@ -116,7 +127,7 @@ const enableCapture = function enableCapture(baseFetchFunction, requestClass, do
       const requestClone = request.clone();
       let response;
       try {
-        response = await baseFetchFunction(...args);
+        response = await baseFetchFunction(requestClone);
 
         if (thisSubsegmentCallback) {
           thisSubsegmentCallback(subsegment, requestClone, response);
@@ -159,8 +170,8 @@ const enableCapture = function enableCapture(baseFetchFunction, requestClass, do
   };
 
   return overridenFetchAsync;
-};
+}
 
 module.exports.captureFetchGlobal = captureFetchGlobal;
 module.exports.captureFetchModule = captureFetchModule;
-module.exports._fetchEnableCapture = enableCapture;
+module.exports.enableCapture = enableCapture;

sdk_contrib/fetch/package.json

@@ -40,7 +40,7 @@
   "repository": "https://github.com/aws/aws-xray-sdk-node/tree/master/sdk_contrib/fetch",
   "devDependencies": {
     "@types/node-fetch": "^2.6.4",
-    "chai-as-promised": "^7.1.1",
+    "chai-as-promised": "=7.1.1",
     "node-fetch": "^2.6.11",
     "ts-expect": "^1.3.0"
   },

sdk_contrib/fetch/test/integration/fetch_p.test.js

@@ -1,3 +1,31 @@
+
+let listener;
+let server;
+let goodUrl;
+let receivedHeaders;
+
+
+before(() => {
+  // Create an HTTP server to receive requests.
+  const http = require('http');
+  server = http.createServer((req, res) => {
+    receivedHeaders = { ...req.headers };
+    // Respond with something
+    res.writeHead(200, { 'Content-Type': 'text/plain' });
+    res.end('Example reply\n');
+  });
+
+  listener = server.listen();
+  const address = server.address();
+  const host = address.family === 'IPv6' ? `[${address.address}]` : address.address;
+  goodUrl = `http://${host}:${address.port}/test`;
+});
+
+after(() => {
+  // close http server
+  listener.close();
+});
+
 describe('Integration tests', function () {
   const chai = require('chai');
   const sinonChai = require('sinon-chai');
@@ -16,12 +44,11 @@ describe('Integration tests', function () {
   const fetchModule = require('node-fetch');
   const Segment = AWSXray.Segment;
   const Subsegment = AWSXray.Subsegment;
-  const goodUrl = 'https://example.org';
   const badUrl = 'http://localhost:1';
 
   const hasGlobalFetch = globalThis.fetch !== undefined;
 
-  describe('captureFetchModule', function () {
+  describe('captureFetchGlobal', function () {
 
     let saveGlobalFetch;
     let mockSegment;
@@ -43,6 +70,7 @@ describe('Integration tests', function () {
       stubAddFetchRequestData = sandbox.stub(mockSubsegment, 'addFetchRequestData');
       stubAddErrorFlag = sandbox.stub(mockSubsegment, 'addErrorFlag');
       stubClose = sandbox.stub(mockSubsegment, 'close');
+      receivedHeaders = {};
     });
 
     afterEach(function () {
@@ -65,6 +93,24 @@ describe('Integration tests', function () {
         stubClose.should.have.been.calledOnce;
       });
 
+      it('adds header', async function () {
+        const spyCallback = sandbox.spy();
+        const fetch = captureFetchGlobal(true, spyCallback);
+        const response = await fetch(goodUrl, { headers: {
+          'foo': 'bar'
+        }});
+        response.status.should.equal(200);
+        receivedHeaders.should.to.have.property('x-amzn-trace-id');
+        receivedHeaders.should.to.have.property('foo', 'bar');
+        (await response.text()).should.contain('Example');
+        stubIsAutomaticMode.should.have.been.called;
+        stubAddNewSubsegment.should.have.been.calledOnce;
+        stubResolveSegment.should.have.been.calledOnce;
+        stubAddFetchRequestData.should.have.been.calledOnce;
+        stubAddErrorFlag.should.not.have.been.calledOnce;
+        stubClose.should.have.been.calledOnce;
+      });
+
       it('sets error flag on failed fetch when global fetch exists', async function () {
         const spyCallback = sandbox.spy();
         const fetch = captureFetchGlobal(true, spyCallback);
@@ -116,6 +162,7 @@ describe('Integration tests', function () {
       const fetch = captureFetchModule(fetchModule, true, spyCallback);
       const response = await fetch(goodUrl);
       response.status.should.equal(200);
+      receivedHeaders.should.to.have.property('x-amzn-trace-id');
       (await response.text()).should.contain('Example');
       stubIsAutomaticMode.should.have.been.called;
       stubAddNewSubsegment.should.have.been.calledOnce;

sdk_contrib/fetch/test/unit/fetch_p.test.js

@@ -339,17 +339,6 @@ describe('Unit tests', function () {
       response.should.equal(stubValidResponse);
     });
 
-    it('resolves to response through proxy when fetch options are supplied', async function() {
-      const activeFetch = captureFetch(true);
-      const proxyStub = sinon.stub();
-      const request = new FetchRequest('https://www.foo.com/test');
-      const response = await activeFetch(request, {
-        dispatcher: proxyStub
-      });
-      stubFetch.should.have.been.calledOnceWith(request, {dispatcher: proxyStub});
-      response.should.equal(stubValidResponse);
-    });
-
     it('calls subsegmentCallback with error upon fetch throwing', async function () {
       const spyCallback = sandbox.spy();
       const activeFetch = captureFetch(true, spyCallback);