fix: fix esm instrument express-session regression (#6741)

Author: pabloerhard

.github/workflows/apm-integrations.yml

@@ -384,6 +384,16 @@ jobs:
       - uses: ./.github/actions/install
       - run: yarn test:plugins:ci
 
+  cookie-session:
+    runs-on: ubuntu-latest
+    env:
+      PLUGINS: express-session
+    steps:
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8
+      - uses: ./.github/actions/plugins/test
+        with:
+          dd_api_key: ${{ secrets.DD_API_KEY }}
+
   fastify:
     runs-on: ubuntu-latest
     env:

integration-tests/helpers/index.js

@@ -368,7 +368,7 @@ async function createSandbox (
  */
 function varySandbox (sandbox, filename, variants, namedVariant, packageName = variants) {
   if (typeof variants === 'string') {
-    const bindingName = variants
+    const bindingName = namedVariant || variants
     variants = {
       default: `import ${bindingName} from '${packageName}'`,
       star: namedVariant

packages/datadog-instrumentations/src/express-session.js

@@ -37,5 +37,6 @@ addHook({
   name: 'express-session',
   versions: ['>=1.5.0']
 }, session => {
+  if (session.default) return session
   return shimmer.wrapFunction(session, wrapSession)
 })

packages/datadog-plugin-cookie-parser/test/integration-test/client.spec.js

@@ -15,7 +15,7 @@ withVersions('cookie-parser', 'cookie-parser', version => {
       this.timeout(50000)
       sandbox = await createSandbox([`'cookie-parser@${version}'`, 'express'], false,
         ['./packages/datadog-plugin-cookie-parser/test/integration-test/*'])
-      variants = varySandbox(sandbox, 'server.mjs', 'cookie-parser', 'cookieParser')
+      variants = varySandbox(sandbox, 'server.mjs', 'cookieParser', undefined, 'cookie-parser')
     })
 
     after(async function () {

packages/datadog-plugin-express-session/test/integration-test/client.spec.js

@@ -0,0 +1,43 @@
+'use strict'
+
+const {
+  createSandbox, varySandbox, curl,
+  FakeAgent, spawnPluginIntegrationTestProc
+} = require('../../../../integration-tests/helpers')
+const { assert } = require('chai')
+const { withVersions } = require('../../../dd-trace/test/setup/mocha')
+
+withVersions('express-session', 'express-session', version => {
+  describe('ESM', () => {
+    let sandbox, variants, proc, agent
+
+    before(async function () {
+      this.timeout(50000)
+      sandbox = await createSandbox([`'express-session@${version}'`, 'express'], false,
+        ['./packages/datadog-plugin-express-session/test/integration-test/*'])
+      variants = varySandbox(sandbox, 'server.mjs', 'expressSession', undefined, 'express-session')
+    })
+
+    after(async function () {
+      this.timeout(50000)
+      await sandbox.remove()
+    })
+
+    beforeEach(async () => {
+      agent = await new FakeAgent().start()
+    })
+
+    afterEach(async () => {
+      proc?.kill()
+      await agent.stop()
+    })
+
+    for (const variant of varySandbox.VARIANTS) {
+      it(`is instrumented loaded with ${variant}`, async () => {
+        proc = await spawnPluginIntegrationTestProc(sandbox.folder, variants[variant], agent.port)
+        const response = await curl(proc)
+        assert.equal(response.headers['x-counter'], '1')
+      })
+    }
+  })
+})

packages/datadog-plugin-express-session/test/integration-test/server.mjs

@@ -0,0 +1,30 @@
+import 'dd-trace/init.js'
+import express from 'express'
+import expressSession from 'express-session'
+import dc from 'dc-polyfill'
+
+const sessionMiddlewareCh = dc.channel('datadog:express-session:middleware:finish')
+let counter = 0
+sessionMiddlewareCh.subscribe(() => {
+  counter += 1
+})
+
+const app = express()
+
+app.use(expressSession({
+  secret: 'secret',
+  resave: false,
+  rolling: true,
+  saveUninitialized: true,
+  genid: () => 'sid_123'
+}))
+
+app.get('/', (req, res) => {
+  res.setHeader('X-Counter', counter)
+  res.send('OK')
+})
+
+const server = app.listen(0, () => {
+  const port = server.address().port
+  process.send({ port })
+})

packages/dd-trace/test/plugins/plugin-structure.spec.js

@@ -19,7 +19,8 @@ const missingPlugins = [
   'datadog-plugin-axios', // we test axios to ensure our functionality works with axios, see: https://github.com/DataDog/dd-trace-js/pull/1469
   'datadog-plugin-limitd-client', // limitd-client instrumentation handles trace context propagation, no tracing is done
   'datadog-plugin-mongoose', // mongoose tracing is done through mongodb-core instrumentation
-  'datadog-plugin-cookie-parser' // cookie-parser does not produce spans
+  'datadog-plugin-cookie-parser', // cookie-parser does not produce spans
+  'datadog-plugin-express-session' // express-session does not produce spans
 ]
 
 // instrumentations that do not have a hook, but are still instrumented