Add Plugin for @azure/functions (#4716)

* adds azure functions plugin

* adds azure_functions plugin to API documentation

* add typescript test for azure functions plugin

* adds integration test for azure-functions plugin

* add licenses for added dev packages

* add azure-functions plugin to github workflow

* use pipe for azure-functions integration test child process

* update azure-functions integration test api route

* refactor azure-functions integration test

* add azure func command to path

* remove yarn.lock file from azure-functions integration test

* allow span kind to be server for azure functions

* Update index.d.ts

Co-authored-by: Roch Devost <roch.devost@datadoghq.com>

* add serverless util

* use built in url parser

* remove serverless logic from web util

* remove wait-on dependency

* remove find-process dependency

* Revert "remove find-process dependency"

This reverts commit 3c004c5.

* call func start directly and remove find-process dependency

* simplify serverless util

* Revert "simplify serverless util"

This reverts commit 91a2dd9.

* simplify serverless util

---------

Co-authored-by: Roch Devost <roch.devost@datadoghq.com>

.github/workflows/plugins.yml

@@ -205,6 +205,14 @@ jobs:
       - uses: actions/checkout@v4
       - uses: ./.github/actions/plugins/upstream
 
+  azure-functions:
+    runs-on: ubuntu-latest
+    env:
+      PLUGINS: azure-functions
+    steps:
+      - uses: actions/checkout@v4
+      - uses: ./.github/actions/plugins/test
+
   bluebird:
     runs-on: ubuntu-latest
     env:

.gitignore

@@ -125,3 +125,4 @@ packages/dd-trace/test/appsec/next/*/package.json
 packages/dd-trace/test/appsec/next/*/node_modules
 packages/dd-trace/test/appsec/next/*/yarn.lock
 !packages/dd-trace/**/telemetry/logs
+packages/datadog-plugin-azure-functions/test/integration-test/fixtures/node_modules

docs/API.md

@@ -28,6 +28,7 @@ tracer.use('pg', {
 <h5 id="aws-sdk"></h5>
 <h5 id="aws-sdk-tags"></h5>
 <h5 id="aws-sdk-config"></h5>
+<h5 id="azure-functions"></h5>
 <h5 id="bunyan"></h5>
 <h5 id="couchbase"></h5>
 <h5 id="cucumber"></h5>
@@ -105,6 +106,7 @@ tracer.use('pg', {
 * [amqplib](./interfaces/export_.plugins.amqplib.html)
 * [avsc](./interfaces/export_.plugins.avsc.html)
 * [aws-sdk](./interfaces/export_.plugins.aws_sdk.html)
+* [azure-functions](./interfaces/export_.plugins.azure_functions.html)
 * [bluebird](./interfaces/export_.plugins.bluebird.html)
 * [couchbase](./interfaces/export_.plugins.couchbase.html)
 * [cucumber](./interfaces/export_.plugins.cucumber.html)

docs/test.ts

@@ -286,6 +286,7 @@ tracer.use('amqplib');
 tracer.use('avsc');
 tracer.use('aws-sdk');
 tracer.use('aws-sdk', awsSdkOptions);
+tracer.use('azure-functions');
 tracer.use('bunyan');
 tracer.use('couchbase');
 tracer.use('cassandra-driver');

ext/types.d.ts

@@ -1,5 +1,6 @@
 declare const types: {
   HTTP: 'http'
+  SERVERLESS: 'serverless'
   WEB: 'web'
 }
 

ext/types.js

@@ -2,5 +2,6 @@
 
 module.exports = {
   HTTP: 'http',
+  SERVERLESS: 'serverless',
   WEB: 'web'
 }

index.d.ts

@@ -149,6 +149,7 @@ interface Plugins {
   "apollo": tracer.plugins.apollo;
   "avsc": tracer.plugins.avsc;
   "aws-sdk": tracer.plugins.aws_sdk;
+  "azure-functions": tracer.plugins.azure_functions;
   "bunyan": tracer.plugins.bunyan;
   "cassandra-driver": tracer.plugins.cassandra_driver;
   "child_process": tracer.plugins.child_process;
@@ -1237,6 +1238,12 @@ declare namespace tracer {
       [key: string]: boolean | Object | undefined;
     }
 
+    /**
+     * This plugin automatically instruments the
+     * @azure/functions module.
+    */
+    interface azure_functions extends Instrumentation {}
+
     /**
      * This plugin patches the [bunyan](https://github.com/trentm/node-bunyan)
      * to automatically inject trace identifiers in log records when the

integration-tests/helpers/index.js

@@ -358,6 +358,7 @@ function assertUUID (actual, msg = 'not a valid UUID') {
 
 module.exports = {
   FakeAgent,
+  hookFile,
   assertObjectContains,
   assertUUID,
   spawnProc,

packages/datadog-instrumentations/src/azure-functions.js

@@ -0,0 +1,48 @@
+'use strict'
+
+const {
+  addHook
+} = require('./helpers/instrument')
+const shimmer = require('../../datadog-shimmer')
+const dc = require('dc-polyfill')
+
+const azureFunctionsChannel = dc.tracingChannel('datadog:azure-functions:invoke')
+
+addHook({ name: '@azure/functions', versions: ['>=4'] }, azureFunction => {
+  const { app } = azureFunction
+
+  shimmer.wrap(app, 'deleteRequest', wrapHandler)
+  shimmer.wrap(app, 'http', wrapHandler)
+  shimmer.wrap(app, 'get', wrapHandler)
+  shimmer.wrap(app, 'patch', wrapHandler)
+  shimmer.wrap(app, 'post', wrapHandler)
+  shimmer.wrap(app, 'put', wrapHandler)
+
+  return azureFunction
+})
+
+// The http methods are overloaded so we need to check which type of argument was passed in order to wrap the handler
+// The arguments are either an object with a handler property or the handler function itself
+function wrapHandler (method) {
+  return function (name, arg) {
+    if (typeof arg === 'object' && arg.hasOwnProperty('handler')) {
+      const options = arg
+      shimmer.wrap(options, 'handler', handler => traceHandler(handler, name, method.name))
+    } else if (typeof arg === 'function') {
+      const handler = arg
+      arguments[1] = shimmer.wrapFunction(handler, handler => traceHandler(handler, name, method.name))
+    }
+    return method.apply(this, arguments)
+  }
+}
+
+function traceHandler (handler, functionName, methodName) {
+  return function (...args) {
+    const httpRequest = args[0]
+    const invocationContext = args[1]
+    return azureFunctionsChannel.tracePromise(
+      handler,
+      { functionName, httpRequest, invocationContext, methodName },
+      this, ...args)
+  }
+}

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

@@ -5,6 +5,7 @@ module.exports = {
   '@apollo/gateway': () => require('../apollo'),
   'apollo-server-core': () => require('../apollo-server-core'),
   '@aws-sdk/smithy-client': () => require('../aws-sdk'),
+  '@azure/functions': () => require('../azure-functions'),
   '@cucumber/cucumber': () => require('../cucumber'),
   '@playwright/test': () => require('../playwright'),
   '@elastic/elasticsearch': () => require('../elasticsearch'),

packages/datadog-plugin-azure-functions/src/index.js

@@ -0,0 +1,77 @@
+'use strict'
+
+const TracingPlugin = require('../../dd-trace/src/plugins/tracing')
+const { storage } = require('../../datadog-core')
+const serverless = require('../../dd-trace/src/plugins/util/serverless')
+const web = require('../../dd-trace/src/plugins/util/web')
+
+const triggerMap = {
+  deleteRequest: 'Http',
+  http: 'Http',
+  get: 'Http',
+  patch: 'Http',
+  post: 'Http',
+  put: 'Http'
+}
+
+class AzureFunctionsPlugin extends TracingPlugin {
+  static get id () { return 'azure-functions' }
+  static get operation () { return 'invoke' }
+  static get kind () { return 'server' }
+  static get type () { return 'serverless' }
+
+  static get prefix () { return 'tracing:datadog:azure-functions:invoke' }
+
+  bindStart (ctx) {
+    const { functionName, methodName } = ctx
+    const store = storage.getStore()
+
+    const span = this.startSpan(this.operationName(), {
+      service: this.serviceName(),
+      type: 'serverless',
+      meta: {
+        'aas.function.name': functionName,
+        'aas.function.trigger': mapTriggerTag(methodName)
+      }
+    }, false)
+
+    ctx.span = span
+    ctx.parentStore = store
+    ctx.currentStore = { ...store, span }
+
+    return ctx.currentStore
+  }
+
+  error (ctx) {
+    this.addError(ctx.error)
+    ctx.currentStore.span.setTag('error.message', ctx.error)
+  }
+
+  asyncEnd (ctx) {
+    const { httpRequest, result = {} } = ctx
+    const path = (new URL(httpRequest.url)).pathname
+    const req = {
+      method: httpRequest.method,
+      headers: Object.fromEntries(httpRequest.headers.entries()),
+      url: path
+    }
+
+    const context = web.patch(req)
+    context.config = this.config
+    context.paths = [path]
+    context.res = { statusCode: result.status }
+    context.span = ctx.currentStore.span
+
+    serverless.finishSpan(context)
+  }
+
+  configure (config) {
+    return super.configure(web.normalizeConfig(config))
+  }
+}
+
+function mapTriggerTag (methodName) {
+  return triggerMap[methodName] || 'Unknown'
+}
+
+module.exports = AzureFunctionsPlugin

packages/datadog-plugin-azure-functions/test/integration-test/client.spec.js

@@ -0,0 +1,100 @@
+'use strict'
+
+const {
+  FakeAgent,
+  hookFile,
+  createSandbox,
+  curlAndAssertMessage
+} = require('../../../../integration-tests/helpers')
+const { spawn } = require('child_process')
+const { assert } = require('chai')
+
+describe('esm', () => {
+  let agent
+  let proc
+  let sandbox
+
+  withVersions('azure-functions', '@azure/functions', version => {
+    before(async function () {
+      this.timeout(50000)
+      sandbox = await createSandbox([`@azure/functions@${version}`, 'azure-functions-core-tools@4'], false,
+        ['./packages/datadog-plugin-azure-functions/test/integration-test/fixtures/*'])
+    })
+
+    after(async function () {
+      this.timeout(50000)
+      await sandbox.remove()
+    })
+
+    beforeEach(async () => {
+      agent = await new FakeAgent().start()
+    })
+
+    afterEach(async () => {
+      proc && proc.kill('SIGINT')
+      await agent.stop()
+    })
+
+    it('is instrumented', async () => {
+      const envArgs = {
+        PATH: `${sandbox.folder}/node_modules/azure-functions-core-tools/bin:${process.env.PATH}`
+      }
+      proc = await spawnPluginIntegrationTestProc(sandbox.folder, 'func', ['start'], agent.port, undefined, envArgs)
+
+      return curlAndAssertMessage(agent, 'http://127.0.0.1:7071/api/httptest', ({ headers, payload }) => {
+        assert.propertyVal(headers, 'host', `127.0.0.1:${agent.port}`)
+        assert.isArray(payload)
+        assert.strictEqual(payload.length, 1)
+        assert.isArray(payload[0])
+        assert.strictEqual(payload[0].length, 1)
+        assert.propertyVal(payload[0][0], 'name', 'azure-functions.invoke')
+      })
+    }).timeout(50000)
+  })
+})
+
+async function spawnPluginIntegrationTestProc (cwd, command, args, agentPort, stdioHandler, additionalEnvArgs = {}) {
+  let env = {
+    NODE_OPTIONS: `--loader=${hookFile}`,
+    DD_TRACE_AGENT_PORT: agentPort
+  }
+  env = { ...env, ...additionalEnvArgs }
+  return spawnProc(command, args, {
+    cwd,
+    env
+  }, stdioHandler)
+}
+
+function spawnProc (command, args, options = {}, stdioHandler, stderrHandler) {
+  const proc = spawn(command, args, { ...options, stdio: 'pipe' })
+  return new Promise((resolve, reject) => {
+    proc
+      .on('error', reject)
+      .on('exit', code => {
+        if (code !== 0) {
+          reject(new Error(`Process exited with status code ${code}.`))
+        }
+        resolve()
+      })
+
+    proc.stdout.on('data', data => {
+      if (stdioHandler) {
+        stdioHandler(data)
+      }
+      // eslint-disable-next-line no-console
+      if (!options.silent) console.log(data.toString())
+
+      if (data.toString().includes('http://localhost:7071/api/httptest')) {
+        resolve(proc)
+      }
+    })
+
+    proc.stderr.on('data', data => {
+      if (stderrHandler) {
+        stderrHandler(data)
+      }
+      // eslint-disable-next-line no-console
+      if (!options.silent) console.error(data.toString())
+    })
+  })
+}

packages/datadog-plugin-azure-functions/test/integration-test/fixtures/host.json

@@ -0,0 +1,15 @@
+{
+  "version": "2.0",
+  "logging": {
+    "applicationInsights": {
+      "samplingSettings": {
+        "isEnabled": true,
+        "excludedTypes": "Request"
+      }
+    }
+  },
+  "extensionBundle": {
+    "id": "Microsoft.Azure.Functions.ExtensionBundle",
+    "version": "[4.*, 5.0.0)"
+  }
+}

packages/datadog-plugin-azure-functions/test/integration-test/fixtures/local.settings.json

@@ -0,0 +1,8 @@
+{
+  "IsEncrypted": false,
+  "Values": {
+    "FUNCTIONS_WORKER_RUNTIME": "node",
+    "AzureWebJobsFeatureFlags": "EnableWorkerIndexing",
+    "AzureWebJobsStorage": ""
+  }
+}

packages/datadog-plugin-azure-functions/test/integration-test/fixtures/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "azure-function-node-integration-test",
+  "version": "1.0.0",
+  "description": "",
+  "main": "src/functions/server.mjs",
+  "scripts": {
+    "start": "func start"
+  },
+  "dependencies": {
+    "@azure/functions": "^4.0.0"
+  },
+  "devDependencies": {
+    "azure-functions-core-tools": "^4.x"
+  }
+}

packages/datadog-plugin-azure-functions/test/integration-test/fixtures/src/functions/server.mjs

@@ -0,0 +1,15 @@
+import 'dd-trace/init.js'
+import { app } from '@azure/functions'
+
+async function handlerFunction (request, context) {
+  return {
+    status: 200,
+    body: 'Hello Datadog!'
+  }
+}
+
+app.http('httptest', {
+  methods: ['GET'],
+  authLevel: 'anonymous',
+  handler: handlerFunction
+})