Hide public profiler instance

benchmarks/profiler_sample_loop.rb

@@ -23,10 +23,10 @@ def create_profiler
     end
 
     # Stop background threads
-    Datadog.profiler.shutdown!
+    Datadog.shutdown!
 
     # Call collection directly
-    @stack_collector = Datadog.profiler.collectors.first
+    @stack_collector = Datadog.send(:components).profiler.collectors.first
     @recorder = @stack_collector.recorder
   end
 

benchmarks/profiler_submission.rb

@@ -37,10 +37,10 @@ def create_profiler
     end
 
     # Stop background threads
-    Datadog.profiler.shutdown!
+    Datadog.shutdown!
 
     # Call exporter directly
-    @exporter = Datadog.profiler.scheduler.exporters.first
+    @exporter = Datadog.send(:components).profiler.scheduler.exporters.first
     @flush = Marshal.load(
       Zlib::GzipReader.new(File.open(ENV['FLUSH_DUMP_FILE'] || 'benchmarks/data/profiler-submission-marshal.gz'))
     )

docs/ProfilingDevelopment.md

@@ -34,8 +34,8 @@ Components below live inside <../lib/datadog/profiling>:
 When started via `ddtracerb exec` (together with `DD_PROFILING_ENABLED=true`), initialization goes through the following
 flow:
 
-1. <../lib/datadog/profiling/preload.rb> triggers the creation of the `Datadog.profiler` instance by calling the method
-2. `Datadog.profiler` is handled by `Datadog::Configuration`, which triggers the configuration of `ddtrace` components
+1. <../lib/datadog/profiling/preload.rb> triggers the creation of the profiler instance by calling the method `Datadog::Profiling.start_if_enabled`
+2. The profiler instance is handled by `Datadog::Configuration`, which triggers the configuration of `ddtrace` components
    in `#build_components`
 3. Inside `Datadog::Components`, the `build_profiler` method triggers the execution of the `Tasks::Setup`
 4. The `Setup` task activates our extensions

integration/apps/rack/app/acme.rb

@@ -89,7 +89,7 @@ def check(request)
       def detailed_check(request)
         ['200', { 'Content-Type' => 'application/json'}, [JSON.pretty_generate(
           webserver_process: $PROGRAM_NAME,
-          profiler_available: !!Datadog.profiler,
+          profiler_available: Datadog::Profiling.start_if_enabled,
           # NOTE: Threads can't be named on Ruby 2.1 and 2.2
           profiler_threads: ((Thread.list.map(&:name).select { |it| it && it.include?('Profiling') }) unless RUBY_VERSION < '2.3')
         )], "\n"]

integration/apps/rack/app/resque_background_job.rb

@@ -28,7 +28,7 @@ def self.perform(key, value)
       key: key,
       value: value,
       resque_process: $PROGRAM_NAME,
-      profiler_available: !!Datadog.profiler,
+      profiler_available: Datadog::Profiling.start_if_enabled,
       # NOTE: Threads can't be named on Ruby 2.1 and 2.2
       profiler_threads: ((Thread.list.map(&:name).select { |it| it && it.include?('Profiling') }) unless RUBY_VERSION < '2.3')
     ))

integration/apps/rack/app/sidekiq_background_job.rb

@@ -26,7 +26,7 @@ def perform(key, value)
       key: key,
       value: value,
       sidekiq_process: $PROGRAM_NAME,
-      profiler_available: !!Datadog.profiler,
+      profiler_available: Datadog::Profiling.start_if_enabled,
       # NOTE: Threads can't be named on Ruby 2.1 and 2.2
       profiler_threads: ((Thread.list.map(&:name).select { |it| it && it.include?('Profiling') }) unless RUBY_VERSION < '2.3')
     ))

integration/apps/rails-five/app/controllers/health_controller.rb

@@ -12,7 +12,7 @@ def check
   def detailed_check
     render json: {
       webserver_process: $PROGRAM_NAME,
-      profiler_available: !!Datadog.profiler,
+      profiler_available: Datadog::Profiling.start_if_enabled,
       profiler_threads: Thread.list.map(&:name).select { |it| it && it.include?('Profiling') }
     }
   end

lib/datadog/core/configuration.rb

@@ -153,8 +153,7 @@ def configuration_for(target, option = nil)
 
       def_delegators \
         :components,
-        :health_metrics,
-        :profiler
+        :health_metrics
 
       def logger
         # avoid initializing components if they didn't already exist

lib/datadog/profiling.rb

@@ -82,6 +82,18 @@ def self.configuration
       )
     end
 
+    # Starts the profiler, if the profiler is supported by in
+    # this runtime environment and if the profiler has been enabled
+    # in configuration.
+    #
+    # @return [Boolean] `true` if the profiler has successfully started, otherwise `false`.
+    # @public_api
+    def self.start_if_enabled
+      # Getting the profiler instance triggers start as a side-effect;
+      # otherwise we get nil
+      !!Datadog.send(:components).profiler
+    end
+
     private_class_method def self.ruby_engine_unsupported?
       'JRuby is not supported' if RUBY_ENGINE == 'jruby'
     end

lib/datadog/profiling/preload.rb

@@ -1,4 +1,4 @@
 # typed: strict
 require 'ddtrace'
 
-Datadog.profiler.start if Datadog.profiler
+Datadog::Profiling.start_if_enabled

lib/datadog/profiling/tasks/setup.rb

@@ -61,7 +61,7 @@ def setup_at_fork_hooks
                 Thread.current.send(:update_native_ids) if Thread.current.respond_to?(:update_native_ids, true)
 
                 # Restart profiler, if enabled
-                Datadog.profiler.start if Datadog.profiler
+                Datadog::Profiling.start_if_enabled
               rescue StandardError => e
                 Datadog.logger.warn do
                   "Error during post-fork hooks. Cause: #{e.message} Location: #{Array(e.backtrace).first}"

lib/ddtrace/auto_instrument.rb

@@ -5,4 +5,4 @@
 require 'ddtrace'
 
 Datadog.add_auto_instrument
-Datadog.profiler.start if Datadog.profiler
+Datadog::Profiling.start_if_enabled

spec/datadog/core/configuration_spec.rb

@@ -325,7 +325,7 @@
 
             it 'starts the profiler' do
               configure
-              expect(test_class.profiler).to have_received(:start)
+              expect(test_class.send(:components).profiler).to have_received(:start)
             end
           end
         end

spec/datadog/profiling/preload_spec.rb

@@ -6,19 +6,8 @@
   subject(:preload) { load 'datadog/profiling/preload.rb' }
 
   it 'starts the profiler' do
-    profiler = instance_double(Datadog::Profiling::Profiler)
-
-    expect(Datadog).to receive(:profiler).and_return(profiler).at_least(:once)
-    expect(profiler).to receive(:start)
+    expect(Datadog::Profiling).to receive(:start_if_enabled)
 
     preload
   end
-
-  context 'when the profiler is not available' do
-    it 'does not raise any error' do
-      expect(Datadog).to receive(:profiler).and_return(nil)
-
-      preload
-    end
-  end
 end

spec/datadog/profiling/tasks/setup_spec.rb

@@ -151,7 +151,7 @@
     context 'when Process#at_fork is available' do
       before do
         allow(Process).to receive(:respond_to?).with(:at_fork).and_return(true)
-        allow(Datadog).to receive(:profiler)
+        allow(Datadog::Profiling).to receive(:start_if_enabled)
 
         without_partial_double_verification do
           allow(Process).to receive(:at_fork)
@@ -173,17 +173,14 @@
       end
 
       it 'sets up an at_fork hook that restarts the profiler' do
-        profiler = instance_double(Datadog::Profiling::Profiler)
-
-        expect(Datadog).to receive(:profiler).and_return(profiler).at_least(:once)
-        expect(profiler).to receive(:start)
+        expect(Datadog::Profiling).to receive(:start_if_enabled)
 
         at_fork_hook.call
       end
 
       context 'when there is an issue starting the profiler' do
         before do
-          expect(Datadog).to receive(:profiler).and_raise('Dummy exception')
+          expect(Datadog::Profiling).to receive(:start_if_enabled).and_raise('Dummy exception')
           allow(Datadog.logger).to receive(:warn) # Silence logging during tests
         end
 

spec/ddtrace/profiling_spec.rb → spec/datadog/profiling_spec.rb

@@ -5,6 +5,64 @@
 RSpec.describe Datadog::Profiling do
   extend ConfigurationHelpers
 
+  describe '.configure' do
+    subject(:configure) { described_class.configure(&block) }
+    let(:block) { proc {} }
+
+    it 'delegates to the global configuration' do
+      expect(Datadog).to receive(:internal_configure) { |&b| expect(b).to be_a_kind_of(Proc) }
+      configure
+    end
+
+    context 'validation' do
+      it 'wraps the configuration object with a proxy' do
+        described_class.configure do |c|
+          expect(c).to be_a_kind_of(Datadog::Core::Configuration::ValidationProxy::Profiling)
+        end
+      end
+
+      it 'allows profiling options' do
+        described_class.configure do |c|
+          expect(c).to respond_to(:profiling)
+        end
+      end
+
+      it 'raises errors for non-profiling options' do
+        described_class.configure do |c|
+          expect(c).to_not respond_to(:tracer)
+        end
+      end
+    end
+  end
+
+  describe '.configuration' do
+    subject(:configuration) { described_class.configuration }
+    it 'returns the global configuration' do
+      expect(configuration)
+        .to be_a_kind_of(Datadog::Core::Configuration::ValidationProxy::Profiling)
+
+      expect(configuration.send(:settings)).to eq(Datadog.send(:internal_configuration))
+    end
+  end
+
+  describe '.start_if_enabled' do
+    subject(:start_if_enabled) { described_class.start_if_enabled }
+
+    before do
+      allow(Datadog.send(:components)).to receive(:profiler).and_return(result)
+    end
+
+    context 'with the profiler instance available' do
+      let(:result) { double }
+      it { is_expected.to be(true) }
+    end
+
+    context 'with the profiler instance not available' do
+      let(:result) { nil }
+      it { is_expected.to be(false) }
+    end
+  end
+
   describe '::supported?' do
     subject(:supported?) { described_class.supported? }
 

spec/ddtrace/auto_instrument_spec.rb

@@ -112,22 +112,7 @@ def migrate_db
   end
 
   it 'starts the profiler' do
-    skip 'Profiling is not supported on JRuby' if PlatformHelpers.jruby?
-    skip 'Profiling is not supported on TruffleRuby' if PlatformHelpers.truffleruby?
-
-    profiler = instance_double('Datadog::Profiling::Profiler')
-
-    expect(Datadog).to receive(:profiler).and_return(profiler).at_least(:once)
-    expect(profiler).to receive(:start)
-
+    expect(Datadog::Profiling).to receive(:start_if_enabled)
     auto_instrument
   end
-
-  context 'when the profiler is not available' do
-    it 'does not raise any error' do
-      expect(Datadog).to receive(:profiler).and_return(nil)
-
-      auto_instrument
-    end
-  end
 end