Code hotspots and endpoint collection don't work on Windows. (#3944)

Author: szegedi

packages/dd-trace/src/profiling/config.js

@@ -92,14 +92,24 @@ class Config {
         logger.warn(`${deprecatedEnvVarName} is deprecated. Use DD_PROFILING_${shortVarName} instead.`)
       }
     }
+    // Profiler sampling contexts are not available on Windows, so features
+    // depending on those (code hotspots and endpoint collection) need to default
+    // to false on Windows.
+    const samplingContextsAvailable = process.platform !== 'win32'
+    function checkOptionAllowed (option, description) {
+      if (option && !samplingContextsAvailable) {
+        throw new Error(`${description} not supported on ${process.platform}.`)
+      }
+    }
     this.flushInterval = flushInterval
     this.uploadTimeout = uploadTimeout
     this.sourceMap = sourceMap
     this.debugSourceMaps = isTrue(coalesce(options.debugSourceMaps, DD_PROFILING_DEBUG_SOURCE_MAPS, false))
     this.endpointCollectionEnabled = isTrue(coalesce(options.endpointCollection,
       DD_PROFILING_ENDPOINT_COLLECTION_ENABLED,
-      DD_PROFILING_EXPERIMENTAL_ENDPOINT_COLLECTION_ENABLED, true))
+      DD_PROFILING_EXPERIMENTAL_ENDPOINT_COLLECTION_ENABLED, samplingContextsAvailable))
     logExperimentalVarDeprecation('ENDPOINT_COLLECTION_ENABLED')
+    checkOptionAllowed(this.endpointCollectionEnabled, 'Endpoint collection')
 
     this.pprofPrefix = pprofPrefix
     this.v8ProfilerBugWorkaroundEnabled = isTrue(coalesce(options.v8ProfilerBugWorkaround,
@@ -148,8 +158,9 @@ class Config {
 
     this.codeHotspotsEnabled = isTrue(coalesce(options.codeHotspotsEnabled,
       DD_PROFILING_CODEHOTSPOTS_ENABLED,
-      DD_PROFILING_EXPERIMENTAL_CODEHOTSPOTS_ENABLED, true))
+      DD_PROFILING_EXPERIMENTAL_CODEHOTSPOTS_ENABLED, samplingContextsAvailable))
     logExperimentalVarDeprecation('CODEHOTSPOTS_ENABLED')
+    checkOptionAllowed(this.codeHotspotsEnabled, 'Code hotspots')
 
     this.cpuProfilingEnabled = isTrue(coalesce(options.cpuProfilingEnabled,
       DD_PROFILING_EXPERIMENTAL_CPU_ENABLED, false))

packages/dd-trace/test/profiling/config.spec.js

@@ -11,6 +11,8 @@ const WallProfiler = require('../../src/profiling/profilers/wall')
 const SpaceProfiler = require('../../src/profiling/profilers/space')
 const { ConsoleLogger } = require('../../src/profiling/loggers/console')
 
+const samplingContextsAvailable = process.platform !== 'win32'
+
 describe('config', () => {
   let Config
   let env
@@ -48,7 +50,7 @@ describe('config', () => {
     expect(config.logger).to.be.an.instanceof(ConsoleLogger)
     expect(config.exporters[0]).to.be.an.instanceof(AgentExporter)
     expect(config.profilers[0]).to.be.an.instanceof(WallProfiler)
-    expect(config.profilers[0].codeHotspotsEnabled()).true
+    expect(config.profilers[0].codeHotspotsEnabled()).to.equal(samplingContextsAvailable)
     expect(config.profilers[1]).to.be.an.instanceof(SpaceProfiler)
     expect(config.v8ProfilerBugWorkaroundEnabled).true
     expect(config.cpuProfilingEnabled).false
@@ -142,7 +144,7 @@ describe('config', () => {
     expect(config.profilers).to.be.an('array')
     expect(config.profilers.length).to.equal(1)
     expect(config.profilers[0]).to.be.an.instanceOf(WallProfiler)
-    expect(config.profilers[0].codeHotspotsEnabled()).true
+    expect(config.profilers[0].codeHotspotsEnabled()).to.equal(samplingContextsAvailable)
     expect(config.v8ProfilerBugWorkaroundEnabled).false
     expect(config.cpuProfilingEnabled).true
   })
@@ -181,6 +183,10 @@ describe('config', () => {
   })
 
   it('should prioritize options over env variables', () => {
+    if (!samplingContextsAvailable) {
+      return
+    }
+
     process.env = {
       DD_PROFILING_PROFILERS: 'space',
       DD_PROFILING_ENDPOINT_COLLECTION_ENABLED: '1'
@@ -202,6 +208,10 @@ describe('config', () => {
   })
 
   it('should prioritize non-experimental env variables and warn about experimental ones', () => {
+    if (!samplingContextsAvailable) {
+      return
+    }
+
     process.env = {
       DD_PROFILING_PROFILERS: 'wall',
       DD_PROFILING_CODEHOTSPOTS_ENABLED: '0',
@@ -238,6 +248,30 @@ describe('config', () => {
     expect(config.profilers[0].endpointCollectionEnabled()).false
   })
 
+  it('should prevent accidentally enabling code hotspots', () => {
+    if (samplingContextsAvailable) {
+      return
+    }
+
+    const options = {
+      codeHotspotsEnabled: true
+    }
+    // eslint-disable-next-line no-new
+    expect(() => { new Config(options) }).to.throw('Code hotspots not supported on ')
+  })
+
+  it('should prevent accidentally enabling endpoint collection', () => {
+    if (samplingContextsAvailable) {
+      return
+    }
+
+    const options = {
+      endpointCollection: true
+    }
+    // eslint-disable-next-line no-new
+    expect(() => { new Config(options) }).to.throw('Endpoint collection not supported on ')
+  })
+
   it('should support tags', () => {
     const tags = {
       env: 'dev'