From 8a10ee489cf53a88d2cf4b5eee8488944a97e97f Mon Sep 17 00:00:00 2001
From: Samuel Williams <samuel.williams@oriontransfer.co.nz>
Date: Fri, 8 Nov 2024 19:42:26 +1300
Subject: [PATCH] Expose traces and metrics providers.

---
 config/metrics.rb                    |  8 ++++++++
 config/sus.rb                        | 14 ++++++++++++++
 config/traces.rb                     |  8 ++++++++
 gems.rb                              |  3 +++
 lib/metrics/provider/async.rb        |  6 ++++++
 lib/metrics/provider/async/task.rb   | 17 ++++++++++++++++
 lib/traces/provider/async.rb         |  7 +++++++
 lib/traces/provider/async/barrier.rb | 17 ++++++++++++++++
 lib/traces/provider/async/task.rb    | 29 ++++++++++++++++++++++++++++
 releases.md                          |  8 ++++++++
 10 files changed, 117 insertions(+)
 create mode 100644 config/metrics.rb
 create mode 100644 config/traces.rb
 create mode 100644 lib/metrics/provider/async.rb
 create mode 100644 lib/metrics/provider/async/task.rb
 create mode 100644 lib/traces/provider/async.rb
 create mode 100644 lib/traces/provider/async/barrier.rb
 create mode 100644 lib/traces/provider/async/task.rb

diff --git a/config/metrics.rb b/config/metrics.rb
new file mode 100644
index 0000000..cdffbbf
--- /dev/null
+++ b/config/metrics.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2024, by Samuel Williams.
+
+def prepare
+	require "metrics/provider/async"
+end
\ No newline at end of file
diff --git a/config/sus.rb b/config/sus.rb
index be5cd75..ed859a7 100644
--- a/config/sus.rb
+++ b/config/sus.rb
@@ -5,3 +5,17 @@
 
 require "covered/sus"
 include Covered::Sus
+
+def prepare_instrumentation!
+	ENV["TRACES_BACKEND"] ||= "traces/backend/test"
+	require "traces"
+
+	ENV["METRICS_BACKEND"] ||= "metrics/backend/test"
+	require "metrics"
+end
+
+def before_tests
+	prepare_instrumentation!
+	
+	super
+end
diff --git a/config/traces.rb b/config/traces.rb
new file mode 100644
index 0000000..b2d0541
--- /dev/null
+++ b/config/traces.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2024, by Samuel Williams.
+
+def prepare
+	require "traces/provider/async"
+end
\ No newline at end of file
diff --git a/gems.rb b/gems.rb
index 706984e..d00bf44 100644
--- a/gems.rb
+++ b/gems.rb
@@ -25,6 +25,9 @@
 	gem "decode"
 	gem "rubocop"
 	
+	gem "traces"
+	gem "metrics"
+	
 	gem "sus-fixtures-async"
 	gem "sus-fixtures-console", "~> 0.3"
 	
diff --git a/lib/metrics/provider/async.rb b/lib/metrics/provider/async.rb
new file mode 100644
index 0000000..a4252d4
--- /dev/null
+++ b/lib/metrics/provider/async.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2024, by Samuel Williams.
+
+require_relative "async/task"
diff --git a/lib/metrics/provider/async/task.rb b/lib/metrics/provider/async/task.rb
new file mode 100644
index 0000000..daf6f8e
--- /dev/null
+++ b/lib/metrics/provider/async/task.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2024, by Samuel Williams.
+
+require_relative "../../../async/task"
+require "metrics/provider"
+
+Metrics::Provider(Async::Task) do
+	ASYNC_TASK_SCHEDULED = Metrics.metric("async.task.scheduled", :counter, description: "The number of tasks scheduled.")
+	
+	def schedule(&block)
+		ASYNC_TASK_SCHEDULED.emit(1)
+		
+		super(&block)
+	end
+end
diff --git a/lib/traces/provider/async.rb b/lib/traces/provider/async.rb
new file mode 100644
index 0000000..ba4de70
--- /dev/null
+++ b/lib/traces/provider/async.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2024, by Samuel Williams.
+
+require_relative "async/task"
+require_relative "async/barrier"
diff --git a/lib/traces/provider/async/barrier.rb b/lib/traces/provider/async/barrier.rb
new file mode 100644
index 0000000..ffa6721
--- /dev/null
+++ b/lib/traces/provider/async/barrier.rb
@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2022, by Samuel Williams.
+
+require_relative "../../../async/barrier"
+require "traces/provider"
+
+Traces::Provider(Async::Barrier) do
+	def wait
+		attributes = {
+			"size" => self.size
+		}
+		
+		Traces.trace("async.barrier.wait", attributes: attributes) {super}
+	end
+end
diff --git a/lib/traces/provider/async/task.rb b/lib/traces/provider/async/task.rb
new file mode 100644
index 0000000..7cb1151
--- /dev/null
+++ b/lib/traces/provider/async/task.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+# Released under the MIT License.
+# Copyright, 2022, by Samuel Williams.
+
+require_relative "../../../async/task"
+require "traces/provider"
+
+Traces::Provider(Async::Task) do
+	def schedule(&block)
+		unless self.transient?
+			trace_context = Traces.trace_context
+		end
+		
+		super do
+			Traces.trace_context = trace_context
+			
+			if annotation = self.annotation
+				attributes = {
+					"annotation" => annotation
+				}
+			end
+			
+			Traces.trace("async.task", attributes: attributes) do
+				yield
+			end
+		end
+	end
+end
diff --git a/releases.md b/releases.md
index 34999f8..6fd9200 100644
--- a/releases.md
+++ b/releases.md
@@ -1,5 +1,13 @@
 # Releases
 
+## Unreleased
+
+### Traces and Metrics Providers
+
+Async now has [traces](https://github.com/socketry/traces) and [metrics](https://github.com/socketry/metrics) providers for various core classes. This allows you to emit traces and metrics to a suitable backend (including DataDog, New Relic, OpenTelemetry, etc.) for monitoring and debugging purposes.
+
+To take advantage of this feature, you will need to introduce your own `config/traces.rb` and `config/metrics.rb`. Async's own repository includes these files for testing purposes, you could copy them into your own project and modify them as needed.
+
 ## v2.19.0
 
 ### Async::Scheduler Debugging