Adjust existing Metrics SDK code to match changes to API

metrics_api/lib/opentelemetry/internal/proxy_instrument.rb

@@ -5,34 +5,18 @@
 # SPDX-License-Identifier: Apache-2.0
 
 module OpenTelemetry
-  module Internal
-    # @api private
-    class ProxyInstrument
-      def initialize(kind, name, unit, desc, callable)
-        @kind = kind
-        @name = name
-        @unit = unit
-        @desc = desc
-        @callable = callable
-        @delegate = nil
-      end
-
-      def upgrade_with(meter)
-        @delegate = case @kind
-                    when :counter, :histogram, :up_down_counter
-                      meter.send("create_#{@kind}", @name, unit: @unit, description: @desc)
-                    when :observable_counter, :observable_gauge, :observable_up_down_counter
-                      meter.send("create_#{@kind}", @name, unit: @unit, description: @desc, callback: @callback)
-                    end
-      end
-
-      def add(amount, attributes: nil)
-        @delegate&.add(amount, attributes: attributes)
-      end
-
-      def record(amount, attributes: nil)
-        @delegate&.record(amount, attributes: attributes)
-      end
+  module Metrics
+    module ProxyInstrument
     end
   end
 end
+
+require 'opentelemetry/internal/proxy_instrument/delegate_synchronous_instrument'
+require 'opentelemetry/internal/proxy_instrument/counter'
+require 'opentelemetry/internal/proxy_instrument/histogram'
+require 'opentelemetry/internal/proxy_instrument/up_down_counter'
+
+require 'opentelemetry/internal/proxy_instrument/delegate_asynchronous_instrument'
+require 'opentelemetry/internal/proxy_instrument/observable_counter'
+require 'opentelemetry/internal/proxy_instrument/observable_gauge'
+require 'opentelemetry/internal/proxy_instrument/observable_up_down_counter'

metrics_api/lib/opentelemetry/internal/proxy_instrument/counter.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      class Counter < Metrics::Instrument::Counter
+        include DelegateSynchronousInstrument
+
+        def add(increment, attributes: nil)
+          @delegate_mutex.synchronize do
+            if @delegate.nil?
+              super
+            else
+              @delegate.add(increment, attributes: attributes)
+            end
+          end
+        end
+      end
+    end
+  end
+end

metrics_api/lib/opentelemetry/internal/proxy_instrument/delegate_asynchronous_instrument.rb

@@ -0,0 +1,53 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      module DelegateAsynchronousInstrument
+        def initialize(*args, **kwargs)
+          super
+
+          @delegate_mutex = Mutex.new
+          @delegate = nil
+        end
+
+        def delegate=(instrument)
+          @delegate_mutex.synchronize do
+            if @delegate.nil?
+              @delegate = instrument
+            else
+              OpenTelemetry.logger.warn(
+                'Attempt to reset delegate in Asynchronous ProxyInstrument ignored'
+              )
+            end
+          end
+        end
+
+        def register_callbacks(*callbacks)
+          @delegate_mutex.synchronize do
+            if @delegate.nil?
+              super
+            else
+              @delegate.register_callbacks(*callbacks)
+            end
+          end
+        end
+
+        def unregister_callbacks(*callbacks)
+          @delegate_mutex.synchronize do
+            if @delegate.nil?
+              super
+            else
+              @delegate.unregister_callbacks(*callbacks)
+            end
+          end
+        end
+      end
+    end
+  end
+end

metrics_api/lib/opentelemetry/internal/proxy_instrument/delegate_synchronous_instrument.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      module DelegateSynchronousInstrument
+        def initialize(*args, **kwargs)
+          super
+
+          @delegate_mutex = Mutex.new
+          @delegate = nil
+        end
+
+        def delegate=(instrument)
+          @delegate_mutex.synchronize do
+            if @delegate.nil?
+              @delegate = instrument
+            else
+              OpenTelemetry.logger.warn('
+                Attempt to reset delegate in Synchronous ProxyInstrument ignored'
+              )
+            end
+          end
+        end
+      end
+    end
+  end
+end

metrics_api/lib/opentelemetry/internal/proxy_instrument/histogram.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      class Histogram < Metrics::Instrument::Histogram
+        include DelegateSynchronousInstrument
+
+        def record(amount, attributes: nil)
+          @delegate_mutex.synchronize do
+            if @delegate.nil?
+              super
+            else
+              @delegate.record(amount, attributes: attributes)
+            end
+          end
+        end
+      end
+    end
+  end
+end

metrics_api/lib/opentelemetry/internal/proxy_instrument/observable_counter.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      class ObservableCounter < Metrics::Instrument::ObservableCounter
+        include DelegateAsynchronousInstrument
+      end
+    end
+  end
+end

metrics_api/lib/opentelemetry/internal/proxy_instrument/observable_gauge.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      class ObservableGauge < Metrics::Instrument::ObservableGauge
+        include DelegateAsynchronousInstrument
+      end
+    end
+  end
+end

metrics_api/lib/opentelemetry/internal/proxy_instrument/observable_up_down_counter.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      class ObservableUpDownCounter < Metrics::Instrument::ObservableUpDownCounter
+        include DelegateAsynchronousInstrument
+      end
+    end
+  end
+end

metrics_api/lib/opentelemetry/internal/proxy_instrument/up_down_counter.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+# Copyright The OpenTelemetry Authors
+#
+# SPDX-License-Identifier: Apache-2.0
+
+module OpenTelemetry
+  module Internal
+    module ProxyInstrument
+      # @api private
+      class UpDownCounter < Metrics::Instrument::UpDownCounter
+        include DelegateSynchronousInstrument
+
+        def add(amount, attributes: nil)
+          @delegate_mutex.synchronize do
+            if @delegate.nil?
+              super
+            else
+              @delegate.add(amount, attributes: attributes)
+            end
+          end
+        end
+      end
+    end
+  end
+end