Add support for exit spans in Code Origin for Spans (#4772)

packages/datadog-code-origin/index.js

@@ -5,15 +5,15 @@ const { getUserLandFrames } = require('../dd-trace/src/plugins/util/stacktrace')
 const limit = Number(process.env._DD_CODE_ORIGIN_MAX_USER_FRAMES) || 8
 
 module.exports = {
-  entryTag,
-  exitTag
+  entryTags,
+  exitTags
 }
 
-function entryTag (topOfStackFunc) {
+function entryTags (topOfStackFunc) {
   return tag('entry', topOfStackFunc)
 }
 
-function exitTag (topOfStackFunc) {
+function exitTags (topOfStackFunc) {
   return tag('exit', topOfStackFunc)
 }
 

packages/datadog-core/src/utils/src/parse-tags.js

@@ -0,0 +1,33 @@
+'use strict'
+
+const digitRegex = /^\d+$/
+
+/**
+ * Converts a flat object of tags into a nested object. For example:
+ *   { 'a.b.c': 'value' } -> { a: { b: { c: 'value' } } }
+ * Also supports array-keys. For example:
+ *   { 'a.0.b': 'value' } -> { a: [{ b: 'value' }] }
+ *
+ * @param {Object} tags - Key/value pairs of tags
+ * @returns Object - Parsed tags
+ */
+module.exports = tags => {
+  const parsedTags = {}
+  for (const [tag, value] of Object.entries(tags)) {
+    const keys = tag.split('.')
+    let current = parsedTags
+    let depth = 0
+    for (const key of keys) {
+      if (!current[key]) {
+        if (depth === keys.length - 1) {
+          current[key] = value
+          break
+        }
+        current[key] = keys[depth + 1]?.match(digitRegex) ? [] : {}
+      }
+      current = current[key]
+      depth++
+    }
+  }
+  return parsedTags
+}

packages/datadog-core/test/utils/src/parse-tags.spec.js

@@ -0,0 +1,23 @@
+'use strict'
+
+require('../../../../dd-trace/test/setup/tap')
+
+const parseTags = require('../../../src/utils/src/parse-tags')
+
+describe('parseTags', () => {
+  it('should parse tags to object', () => {
+    const obj = {
+      'a.0.a': 'foo',
+      'a.0.b': 'bar',
+      'a.1.a': 'baz'
+    }
+
+    expect(parseTags(obj)).to.deep.equal({
+      a: [{ a: 'foo', b: 'bar' }, { a: 'baz' }]
+    })
+  })
+
+  it('should work with empty object', () => {
+    expect(parseTags({})).to.deep.equal({})
+  })
+})

packages/datadog-plugin-fastify/src/code_origin.js

@@ -1,6 +1,6 @@
 'use strict'
 
-const { entryTag } = require('../../datadog-code-origin')
+const { entryTags } = require('../../datadog-code-origin')
 const Plugin = require('../../dd-trace/src/plugins/plugin')
 const web = require('../../dd-trace/src/plugins/util/web')
 
@@ -23,7 +23,7 @@ class FastifyCodeOriginForSpansPlugin extends Plugin {
 
     this.addSub('apm:fastify:route:added', ({ routeOptions, onRoute }) => {
       if (!routeOptions.config) routeOptions.config = {}
-      routeOptions.config[kCodeOriginForSpansTagsSym] = entryTag(onRoute)
+      routeOptions.config[kCodeOriginForSpansTagsSym] = entryTags(onRoute)
     })
   }
 }

packages/datadog-plugin-fastify/test/code_origin.spec.js

@@ -3,6 +3,7 @@
 const axios = require('axios')
 const semver = require('semver')
 const agent = require('../../dd-trace/test/plugins/agent')
+const { getNextLineNumber } = require('../../dd-trace/test/plugins/helpers')
 const { NODE_MAJOR } = require('../../../version')
 
 const host = 'localhost'
@@ -49,13 +50,13 @@ describe('Plugin', () => {
 
             // Wrap in a named function to have at least one frame with a function name
             function wrapperFunction () {
-              routeRegisterLine = getNextLineNumber()
+              routeRegisterLine = String(getNextLineNumber())
               app.get('/user', function userHandler (request, reply) {
                 reply.send()
               })
             }
 
-            const callWrapperLine = getNextLineNumber()
+            const callWrapperLine = String(getNextLineNumber())
             wrapperFunction()
 
             app.listen(() => {
@@ -95,7 +96,7 @@ describe('Plugin', () => {
             let routeRegisterLine
 
             app.register(function v1Handler (app, opts, done) {
-              routeRegisterLine = getNextLineNumber()
+              routeRegisterLine = String(getNextLineNumber())
               app.get('/user', function userHandler (request, reply) {
                 reply.send()
               })
@@ -134,7 +135,7 @@ describe('Plugin', () => {
               next()
             })
 
-            const routeRegisterLine = getNextLineNumber()
+            const routeRegisterLine = String(getNextLineNumber())
             app.get('/user', function userHandler (request, reply) {
               reply.send()
             })
@@ -170,7 +171,7 @@ describe('Plugin', () => {
           // number of where the route handler is defined. However, this might not be the right choice and it might be
           // better to point to the middleware.
           it.skip('should point to middleware if middleware responds early', function testCase (done) {
-            const middlewareRegisterLine = getNextLineNumber()
+            const middlewareRegisterLine = String(getNextLineNumber())
             app.use(function middleware (req, res, next) {
               res.end()
             })
@@ -210,7 +211,3 @@ describe('Plugin', () => {
     })
   })
 })
-
-function getNextLineNumber () {
-  return String(Number(new Error().stack.split('\n')[2].match(/:(\d+):/)[1]) + 1)
-}

packages/datadog-plugin-http/test/code_origin.spec.js

@@ -0,0 +1,63 @@
+'use strict'
+
+const agent = require('../../dd-trace/test/plugins/agent')
+
+describe('Plugin', () => {
+  describe('http', () => {
+    describe('Code Origin for Spans', () => {
+      before(() => {
+        // Needed when this spec file run together with other spec files, in which case the agent config is not
+        // re-loaded unless the existing agent is wiped first. And we need the agent config to be re-loaded in order to
+        // enable Code Origin for Spans.
+        agent.wipe()
+      })
+
+      beforeEach(async () => {
+        return agent.load('http', { server: false }, { codeOriginForSpans: { enabled: true } })
+      })
+
+      afterEach(() => {
+        return agent.close({ ritmReset: false })
+      })
+
+      it('should add code_origin tags for outbound requests', done => {
+        server((port) => {
+          const http = require('http')
+
+          agent
+            .use(traces => {
+              const span = traces[0][0]
+              expect(span.meta).to.have.property('_dd.code_origin.type', 'exit')
+
+              // Just validate that frame 0 tags are present. The detailed validation is performed in a different test.
+              expect(span.meta).to.have.property('_dd.code_origin.frames.0.file')
+              expect(span.meta).to.have.property('_dd.code_origin.frames.0.line')
+              expect(span.meta).to.have.property('_dd.code_origin.frames.0.column')
+              expect(span.meta).to.have.property('_dd.code_origin.frames.0.method')
+              expect(span.meta).to.have.property('_dd.code_origin.frames.0.type')
+            })
+            .then(done)
+            .catch(done)
+
+          const req = http.request(`http://localhost:${port}/`, res => {
+            res.resume()
+          })
+
+          req.end()
+        })
+      })
+    })
+  })
+})
+
+function server (callback) {
+  const http = require('http')
+
+  const server = http.createServer((req, res) => {
+    res.end()
+  })
+
+  server.listen(() => {
+    callback(server.address().port)
+  })
+}

packages/dd-trace/src/plugins/outbound.js

@@ -7,6 +7,7 @@ const {
   PEER_SERVICE_REMAP_KEY
 } = require('../constants')
 const TracingPlugin = require('./tracing')
+const { exitTags } = require('../../../datadog-code-origin')
 
 const COMMON_PEER_SVC_SOURCE_TAGS = [
   'net.peer.name',
@@ -25,6 +26,14 @@ class OutboundPlugin extends TracingPlugin {
     })
   }
 
+  startSpan (...args) {
+    const span = super.startSpan(...args)
+    if (this._tracerConfig.codeOriginForSpans.enabled) {
+      span.addTags(exitTags(this.startSpan))
+    }
+    return span
+  }
+
   getPeerService (tags) {
     /**
      * Compute `peer.service` and associated metadata from available tags, based

packages/dd-trace/test/plugins/helpers.js

@@ -117,11 +117,16 @@ function unbreakThen (promise) {
   }
 }
 
+function getNextLineNumber () {
+  return Number(new Error().stack.split('\n')[2].match(/:(\d+):/)[1]) + 1
+}
+
 module.exports = {
   breakThen,
   compare,
   deepInclude,
   expectSomeSpan,
+  getNextLineNumber,
   resolveNaming,
   unbreakThen,
   withDefaults

packages/dd-trace/test/plugins/outbound.spec.js

@@ -3,7 +3,9 @@
 require('../setup/tap')
 
 const { expect } = require('chai')
+const { getNextLineNumber } = require('./helpers')
 const OutboundPlugin = require('../../src/plugins/outbound')
+const parseTags = require('../../../datadog-core/src/utils/src/parse-tags')
 
 describe('OuboundPlugin', () => {
   describe('peer service decision', () => {
@@ -157,4 +159,50 @@ describe('OuboundPlugin', () => {
       })
     })
   })
+
+  describe('code origin tags', () => {
+    let instance = null
+
+    beforeEach(() => {
+      const tracerStub = {
+        _tracer: {
+          startSpan: sinon.stub().returns({
+            addTags: sinon.spy()
+          })
+        }
+      }
+      instance = new OutboundPlugin(tracerStub)
+    })
+
+    it('should not add exit tags to span if codeOriginForSpans.enabled is false', () => {
+      sinon.stub(instance, '_tracerConfig').value({ codeOriginForSpans: { enabled: false } })
+      const span = instance.startSpan('test')
+      expect(span.addTags).to.not.have.been.called
+    })
+
+    it('should add exit tags to span if codeOriginForSpans.enabled is true', () => {
+      sinon.stub(instance, '_tracerConfig').value({ codeOriginForSpans: { enabled: true } })
+
+      const lineNumber = String(getNextLineNumber())
+      const span = instance.startSpan('test')
+
+      expect(span.addTags).to.have.been.calledOnce
+      const args = span.addTags.args[0]
+      expect(args).to.have.property('length', 1)
+      const tags = parseTags(args[0])
+
+      expect(tags).to.nested.include({ '_dd.code_origin.type': 'exit' })
+      expect(tags._dd.code_origin).to.have.property('frames').to.be.an('array').with.length.above(0)
+
+      for (const frame of tags._dd.code_origin.frames) {
+        expect(frame).to.have.property('file', __filename)
+        expect(frame).to.have.property('line').to.match(/^\d+$/)
+        expect(frame).to.have.property('column').to.match(/^\d+$/)
+        expect(frame).to.have.property('type').to.a('string')
+      }
+
+      const topFrame = tags._dd.code_origin.frames[0]
+      expect(topFrame).to.have.property('line', lineNumber)
+    })
+  })
 })

packages/dd-trace/test/plugins/util/stacktrace.spec.js

@@ -1,6 +1,7 @@
 'use strict'
 
 const { isAbsolute } = require('path')
+const { getNextLineNumber } = require('../helpers')
 
 require('../../setup/tap')
 
@@ -62,7 +63,3 @@ describe('stacktrace utils', () => {
     })
   })
 })
-
-function getNextLineNumber () {
-  return Number(new Error().stack.split('\n')[2].match(/:(\d+):/)[1]) + 1
-}