feat: add opentelemetry instrumentation

google-apis-core/Gemfile

@@ -20,6 +20,7 @@ group :development do
   gem 'redis', '~> 3.2'
   gem 'logging', '~> 2.2'
   gem 'opencensus', '~> 0.4'
+  gem 'opentelemetry-sdk', '~> 0.15.0'
   gem 'httparty'
 end
 

google-apis-core/google-apis-core.gemspec

@@ -19,6 +19,7 @@ Gem::Specification.new do |gem|
   gem.require_paths = ["lib"]
 
   gem.required_ruby_version = '>= 2.5'
+  gem.add_runtime_dependency "opentelemetry-api", '~> 0.15.0'
   gem.add_runtime_dependency "representable", "~> 3.0"
   gem.add_runtime_dependency "retriable", ">= 2.0", "< 4.0"
   gem.add_runtime_dependency "addressable", "~> 2.5", ">= 2.5.1"

google-apis-core/lib/google/apis/core/http_command.rb

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+require 'google/apis/core/opentelemetry'
 require 'addressable/uri'
 require 'addressable/template'
 require 'google/apis/options'
@@ -97,6 +98,7 @@ def initialize(method, url, body: nil)
         # @raise [Google::Apis::AuthorizationError] Authorization is required
         def execute(client)
           prepare!
+          opentelemetry_begin_span
           opencensus_begin_span
           begin
             Retriable.retriable tries: options.retries + 1,
@@ -125,6 +127,7 @@ def execute(client)
             end
           end
         ensure
+          opentelemetry_end_span
           opencensus_end_span
           @http_res = nil
           release!
@@ -355,7 +358,46 @@ def safe_response_representation http_res
           http_res.inspect
         end
 
+        def opentelemetry_begin_span
+          return unless Google::Apis::Core::OpenTelemetry.instance.installed?
+          return if @opentelemetry_span
+
+          attributes = {
+            'http.host' => url.host.to_s,
+            'http.method' => method.to_s,
+            'http.target' => url.path.to_s,
+            'peer.service' => url.host.to_s
+          }
+
+          @opentelemetry_span = Google::Apis::Core::OpenTelemetry.instance.tracer.start_span(url.host.to_s, attributes: attributes)
+        rescue StandardError => e
+          # Log exceptions and continue, so OpenTelemetry failures don't cause
+          # the entire request to fail.
+          logger.debug("Error opening OpenTelemetry span: #{e}")
+        end
+
+        def opentelemetry_end_span
+          return unless Google::Apis::Core::OpenTelemetry.instance.installed?
+          return unless @opentelemetry_span
+
+          if @http_res
+            status_code = @http_res.status.to_i
+            @opentelemetry_span.set_attribute('http.status_code', status_code)
+            @opentelemetry_span.status = ::OpenTelemetry::Trace::Status.http_to_status(
+              status_code
+            )
+          end
+
+          @opentelemetry_span.finish
+          @opentelemetry_span = nil
+        rescue StandardError => e
+          # Log exceptions and continue, so failures don't cause leaks by
+          # aborting cleanup.
+          logger.debug("Error finishing OpenTelemetry span: #{e}")
+        end
+
         def opencensus_begin_span
+          return if Google::Apis::Core::OpenTelemetry.instance.installed?
           return unless OPENCENSUS_AVAILABLE && options.use_opencensus
           return if @opencensus_span
           return unless OpenCensus::Trace.span_context
@@ -381,6 +423,7 @@ def opencensus_begin_span
         end
 
         def opencensus_end_span
+          return if Google::Apis::Core::OpenTelemetry.instance.installed?
           return unless OPENCENSUS_AVAILABLE
           return unless @opencensus_span
           return unless OpenCensus::Trace.span_context

google-apis-core/lib/google/apis/core/opentelemetry.rb

@@ -0,0 +1,26 @@
+# Copyright 2020 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+require 'opentelemetry-api'
+
+module Google
+  module Apis
+    module Core
+      class OpenTelemetry < OpenTelemetry::Instrumentation::Base
+        install { true }
+        present { true }
+      end
+    end
+  end
+end

google-apis-core/spec/google/apis/core/http_command_spec.rb

@@ -14,6 +14,14 @@
 
 require 'spec_helper'
 require 'google/apis/core/http_command'
+require 'opentelemetry-sdk'
+
+EXPORTER = OpenTelemetry::SDK::Trace::Export::InMemorySpanExporter.new
+SPAN_PROCESSOR = OpenTelemetry::SDK::Trace::Export::SimpleSpanProcessor.new(EXPORTER)
+
+OpenTelemetry::SDK.configure do |c|
+  c.add_span_processor SPAN_PROCESSOR
+end
 
 module Google
   module Apis
@@ -392,8 +400,83 @@ class DecryptResponse
         expect(spans.size).to eql 0
       end
     end
+
+    it 'should not attempt to create an opentelemetry span' do
+      stub_request(:get, 'https://www.googleapis.com/zoo/animals').to_return(status: [200, ''])
+      command = Google::Apis::Core::HttpCommand.new(:get, 'https://www.googleapis.com/zoo/animals')
+
+      expect(Google::Apis::Core::OpenTelemetry.instance.tracer).not_to receive(:start_span)
+      command.execute(client)
+    end
   end if Google::Apis::Core::HttpCommand::OPENCENSUS_AVAILABLE
 
+  context('with opentelemetry integration installed') do
+    let(:instrumentation) { Google::Apis::Core::OpenTelemetry.instance }
+    let(:span) { EXPORTER.finished_spans.first }
+
+    before do
+      EXPORTER.reset
+      instrumentation.install
+    end
+
+    after { instrumentation.instance_variable_set(:@installed, false) }
+
+    it 'should not attempt to create an opencesus span' do
+      stub_request(:get, 'https://www.googleapis.com/zoo/animals').to_return(status: [200, ''], body: "Hello world")
+      command = Google::Apis::Core::HttpCommand.new(:get, 'https://www.googleapis.com/zoo/animals')
+      command.execute(client)
+
+      expect(Google::Apis::Core::HttpCommand::OPENCENSUS_AVAILABLE).to be(true)
+      expect(OpenCensus::Trace).not_to receive(:start_span)
+      expect(OpenCensus::Trace).not_to receive(:end)
+      command.execute(client)
+    end
+
+    it 'should create an OpenTelemetry span for a successful call' do
+      stub_request(:get, 'https://www.googleapis.com/zoo/animals').to_return(status: [200, ''], body: "Hello world")
+      command = Google::Apis::Core::HttpCommand.new(:get, 'https://www.googleapis.com/zoo/animals')
+      command.execute(client)
+
+      expect(span.name).to eq('www.googleapis.com')
+      expect(span.status).to be_ok
+      expect(span.instrumentation_library.name).to eq('Google::Apis::Core')
+      expect(span.instrumentation_library.version).to eq(Google::Apis::Core::VERSION)
+      expect(span.attributes).to include(
+        'http.host' => 'www.googleapis.com',
+        'http.method' => 'get',
+        'http.target' => '/zoo/animals',
+        'peer.service' => 'www.googleapis.com',
+        'http.status_code' => 200
+      )
+    end
+
+    it 'should create an OpenTelemetry span for a call failure' do
+      stub_request(:get, 'https://www.googleapis.com/zoo/animals').to_return(status: [403, ''])
+      command = Google::Apis::Core::HttpCommand.new(:get, 'https://www.googleapis.com/zoo/animals')
+      expect { command.execute(client) }.to raise_error(Google::Apis::ClientError)
+
+      expect(span.name).to eq('www.googleapis.com')
+      expect(span.status).not_to be_ok
+      expect(span.attributes).to include(
+        'http.host' => 'www.googleapis.com',
+        'http.method' => 'get',
+        'http.target' => '/zoo/animals',
+        'peer.service' => 'www.googleapis.com',
+        'http.status_code' => 403
+      )
+    end
+
+    it 'should not create an OpenTelemetry span if not installed' do
+      instrumentation.instance_variable_set(:@installed, false)
+      stub_request(:get, 'https://www.googleapis.com/zoo/animals').to_return(status: [200, ''])
+      command = Google::Apis::Core::HttpCommand.new(:get, 'https://www.googleapis.com/zoo/animals')
+
+      expect(instrumentation.tracer).not_to receive(:start_span)
+      command.execute(client)
+      expect(span).to be_nil
+    end
+  end
+
   it 'should send repeated query parameters' do
     stub_request(:get, 'https://www.googleapis.com/zoo/animals?a=1&a=2&a=3')
       .to_return(status: [200, ''])