Express 5 Instrumentation (#4913)

Co-authored-by: William Conti <william.conti@datadoghq.com>
Co-authored-by: simon-id <simon.id@datadoghq.com>

packages/datadog-instrumentations/src/express.js

@@ -59,8 +59,6 @@ function wrapResponseRender (render) {
 
 addHook({ name: 'express', versions: ['>=4'] }, express => {
   shimmer.wrap(express.application, 'handle', wrapHandle)
-  shimmer.wrap(express.Router, 'use', wrapRouterMethod)
-  shimmer.wrap(express.Router, 'route', wrapRouterMethod)
 
   shimmer.wrap(express.response, 'json', wrapResponseJson)
   shimmer.wrap(express.response, 'jsonp', wrapResponseJson)
@@ -69,6 +67,20 @@ addHook({ name: 'express', versions: ['>=4'] }, express => {
   return express
 })
 
+addHook({ name: 'express', versions: ['4'] }, express => {
+  shimmer.wrap(express.Router, 'use', wrapRouterMethod)
+  shimmer.wrap(express.Router, 'route', wrapRouterMethod)
+
+  return express
+})
+
+addHook({ name: 'express', versions: ['>=5.0.0'] }, express => {
+  shimmer.wrap(express.Router.prototype, 'use', wrapRouterMethod)
+  shimmer.wrap(express.Router.prototype, 'route', wrapRouterMethod)
+
+  return express
+})
+
 const queryParserReadCh = channel('datadog:query:read:finish')
 
 function publishQueryParsedAndNext (req, res, next) {
@@ -88,7 +100,7 @@ function publishQueryParsedAndNext (req, res, next) {
 
 addHook({
   name: 'express',
-  versions: ['>=4'],
+  versions: ['4'],
   file: 'lib/middleware/query.js'
 }, query => {
   return shimmer.wrapFunction(query, query => function () {
@@ -129,7 +141,29 @@ addHook({ name: 'express', versions: ['>=4.0.0 <4.3.0'] }, express => {
   return express
 })
 
-addHook({ name: 'express', versions: ['>=4.3.0'] }, express => {
+addHook({ name: 'express', versions: ['>=4.3.0 <5.0.0'] }, express => {
   shimmer.wrap(express.Router, 'process_params', wrapProcessParamsMethod(2))
   return express
 })
+
+const queryReadCh = channel('datadog:express:query:finish')
+
+addHook({ name: 'express', file: ['lib/request.js'], versions: ['>=5.0.0'] }, request => {
+  const requestDescriptor = Object.getOwnPropertyDescriptor(request, 'query')
+
+  shimmer.wrap(requestDescriptor, 'get', function (originalGet) {
+    return function wrappedGet () {
+      const query = originalGet.apply(this, arguments)
+
+      if (queryReadCh.hasSubscribers && query) {
+        queryReadCh.publish({ query })
+      }
+
+      return query
+    }
+  })
+
+  Object.defineProperty(request, 'query', requestDescriptor)
+
+  return request
+})

packages/datadog-instrumentations/src/helpers/hooks.js

@@ -111,7 +111,6 @@ module.exports = {
   protobufjs: () => require('../protobufjs'),
   pug: () => require('../pug'),
   q: () => require('../q'),
-  qs: () => require('../qs'),
   redis: () => require('../redis'),
   restify: () => require('../restify'),
   rhea: () => require('../rhea'),

packages/datadog-instrumentations/src/router.js

@@ -169,11 +169,107 @@ function createWrapRouterMethod (name) {
 
 const wrapRouterMethod = createWrapRouterMethod('router')
 
-addHook({ name: 'router', versions: ['>=1'] }, Router => {
+addHook({ name: 'router', versions: ['>=1 <2'] }, Router => {
   shimmer.wrap(Router.prototype, 'use', wrapRouterMethod)
   shimmer.wrap(Router.prototype, 'route', wrapRouterMethod)
 
   return Router
 })
 
+const queryParserReadCh = channel('datadog:query:read:finish')
+
+addHook({ name: 'router', versions: ['>=2'] }, Router => {
+  const WrappedRouter = shimmer.wrapFunction(Router, function (originalRouter) {
+    return function wrappedMethod () {
+      const router = originalRouter.apply(this, arguments)
+
+      shimmer.wrap(router, 'handle', function wrapHandle (originalHandle) {
+        return function wrappedHandle (req, res, next) {
+          const abortController = new AbortController()
+
+          if (queryParserReadCh.hasSubscribers && req) {
+            queryParserReadCh.publish({ req, res, query: req.query, abortController })
+
+            if (abortController.signal.aborted) return
+          }
+
+          return originalHandle.apply(this, arguments)
+        }
+      })
+
+      return router
+    }
+  })
+
+  shimmer.wrap(WrappedRouter.prototype, 'use', wrapRouterMethod)
+  shimmer.wrap(WrappedRouter.prototype, 'route', wrapRouterMethod)
+
+  return WrappedRouter
+})
+
+const routerParamStartCh = channel('datadog:router:param:start')
+const visitedParams = new WeakSet()
+
+function wrapHandleRequest (original) {
+  return function wrappedHandleRequest (req, res, next) {
+    if (routerParamStartCh.hasSubscribers && Object.keys(req.params).length && !visitedParams.has(req.params)) {
+      visitedParams.add(req.params)
+
+      const abortController = new AbortController()
+
+      routerParamStartCh.publish({
+        req,
+        res,
+        params: req?.params,
+        abortController
+      })
+
+      if (abortController.signal.aborted) return
+    }
+
+    return original.apply(this, arguments)
+  }
+}
+
+addHook({
+  name: 'router', file: 'lib/layer.js', versions: ['>=2']
+}, Layer => {
+  shimmer.wrap(Layer.prototype, 'handleRequest', wrapHandleRequest)
+  return Layer
+})
+
+function wrapParam (original) {
+  return function wrappedProcessParams () {
+    arguments[1] = shimmer.wrapFunction(arguments[1], (originalFn) => {
+      return function wrappedFn (req, res) {
+        if (routerParamStartCh.hasSubscribers && Object.keys(req.params).length && !visitedParams.has(req.params)) {
+          visitedParams.add(req.params)
+
+          const abortController = new AbortController()
+
+          routerParamStartCh.publish({
+            req,
+            res,
+            params: req?.params,
+            abortController
+          })
+
+          if (abortController.signal.aborted) return
+        }
+
+        return originalFn.apply(this, arguments)
+      }
+    })
+
+    return original.apply(this, arguments)
+  }
+}
+
+addHook({
+  name: 'router', versions: ['>=2']
+}, router => {
+  shimmer.wrap(router.prototype, 'param', wrapParam)
+  return router
+})
+
 module.exports = { createWrapRouterMethod }

packages/datadog-instrumentations/test/express.spec.js

@@ -14,7 +14,7 @@ withVersions('express', 'express', version => {
     })
 
     before((done) => {
-      const express = require('../../../versions/express').get()
+      const express = require(`../../../versions/express@${version}`).get()
       const app = express()
       app.get('/', (req, res) => {
         requestBody()