Roda Integration

Rakefile

@@ -158,6 +158,7 @@ namespace :spec do
     :rake,
     :redis,
     :resque,
+    :roda,
     :rest_client,
     :semantic_logger,
     :sequel,
@@ -314,6 +315,7 @@ task :ci do
   declare '✅ 2.1 / ✅ 2.2 / ✅ 2.3 / ✅ 2.4 / ✅ 2.5 / ✅ 2.6 / ✅ 2.7 / ✅ 3.0 / ✅ 3.1 / ✅ 3.2 / ✅ jruby' => 'bundle exec appraisal contrib rake spec:rake'
   declare '✅ 2.1 / ✅ 2.2 / ✅ 2.3 / ✅ 2.4 / ✅ 2.5 / ✅ 2.6 / ✅ 2.7 / ✅ 3.0 / ✅ 3.1 / ✅ 3.2 / ✅ jruby' => 'bundle exec appraisal contrib rake spec:resque'
   declare '✅ 2.1 / ✅ 2.2 / ✅ 2.3 / ✅ 2.4 / ✅ 2.5 / ✅ 2.6 / ✅ 2.7 / ✅ 3.0 / ✅ 3.1 / ✅ 3.2 / ✅ jruby' => 'bundle exec appraisal contrib rake spec:rest_client'
+  declare '✅ 2.1 / ✅ 2.2 / ✅ 2.3 / ✅ 2.4 / ✅ 2.5 / ✅ 2.6 / ✅ 2.7 / ✅ 3.0 / ✅ 3.1 / ✅ 3.2 / ✅ jruby' => 'bundle exec appraisal contrib rake spec:roda'
   declare '✅ 2.1 / ✅ 2.2 / ✅ 2.3 / ✅ 2.4 / ✅ 2.5 / ✅ 2.6 / ✅ 2.7 / ✅ 3.0 / ✅ 3.1 / ✅ 3.2 / ✅ jruby' => 'bundle exec appraisal contrib rake spec:rspec'
   declare '✅ 2.1 / ✅ 2.2 / ✅ 2.3 / ✅ 2.4 / ✅ 2.5 / ✅ 2.6 / ✅ 2.7 / ✅ 3.0 / ✅ 3.1 / ✅ 3.2 / ✅ jruby' => 'bundle exec appraisal contrib rake spec:semantic_logger'
   declare '✅ 2.1 / ✅ 2.2 / ✅ 2.3 / ✅ 2.4 / ✅ 2.5 / ✅ 2.6 / ✅ 2.7 / ✅ 3.0 / ✅ 3.1 / ✅ 3.2 / ✅ jruby' => 'bundle exec appraisal contrib rake spec:sequel'

docs/GettingStarted.md

@@ -74,6 +74,7 @@ To contribute, check out the [contribution guidelines][contribution docs] and [d
      - [Redis](#redis)
      - [Resque](#resque)
      - [Rest Client](#rest-client)
+     - [Roda](#roda)
      - [RSpec](#rspec)
      - [Sequel](#sequel)
      - [Shoryuken](#shoryuken)
@@ -515,6 +516,7 @@ For a list of available integrations, and their configuration options, please re
 | Redis                      | `redis`                    | `>= 3.2`                 | `>= 3.2`                 | *[Link](#redis)*                    | *[Link](https://github.com/redis/redis-rb)*                                    |
 | Resque                     | `resque`                   | `>= 1.0`                 | `>= 1.0`                  | *[Link](#resque)*                   | *[Link](https://github.com/resque/resque)*                                     |
 | Rest Client                | `rest-client`              | `>= 1.8`                 | `>= 1.8`                  | *[Link](#rest-client)*              | *[Link](https://github.com/rest-client/rest-client)*                           |
+| Roda                       | `roda`                     | `>= 2.1, <4`             | `>= 2.1, <4`              | *[Link](#roda)*                     | *[Link](https://github.com/jeremyevans/roda)*                                  |
 | Sequel                     | `sequel`                   | `>= 3.41`                | `>= 3.41`                 | *[Link](#sequel)*                   | *[Link](https://github.com/jeremyevans/sequel)*                                |
 | Shoryuken                  | `shoryuken`                | `>= 3.2`                 | `>= 3.2`                  | *[Link](#shoryuken)*                | *[Link](https://github.com/phstc/shoryuken)*                                   |
 | Sidekiq                    | `sidekiq`                  | `>= 3.5.4`               | `>= 3.5.4`                | *[Link](#sidekiq)*                  | *[Link](https://github.com/mperham/sidekiq)*                                   |
@@ -1873,6 +1875,39 @@ end
 | `service_name` | Service name for `rest_client` instrumentation. | `'rest_client'` |
 | `split_by_domain` | Uses the request domain as the service name when set to `true`. | `false` |
 
+### Roda
+
+The Roda integration traces requests.
+
+The **Roda** integration can be enabled through `Datadog.configure`. It is recommended to use this integration with **Rack** through `use Datadog::Tracing::Contrib::Rack::TraceMiddleware` for distributed tracing.
+
+```ruby
+require "roda"
+require "ddtrace"
+
+class SampleApp < Roda
+  use Datadog::Tracing::Contrib::Rack::TraceMiddleware
+
+  Datadog.configure do |c|
+    c.tracing.instrument :roda, **options
+  end
+
+  route do |r|
+    r.root do
+      r.get do
+        'Hello World!'
+      end
+    end
+  end
+end
+```
+
+`options` are the following keyword arguments:
+
+| Key | Description | Default |
+| --- | ----------- | ------- |
+| `service_name` | Service name for `roda` instrumentation. | `'nil'` |
+
 ### RSpec
 
 RSpec integration will trace all executions of example groups and examples when using `rspec` test framework.

lib/datadog/tracing/contrib.rb

@@ -67,6 +67,7 @@ module Contrib
 require_relative 'contrib/redis/integration'
 require_relative 'contrib/resque/integration'
 require_relative 'contrib/rest_client/integration'
+require_relative 'contrib/roda/integration'
 require_relative 'contrib/semantic_logger/integration'
 require_relative 'contrib/sequel/integration'
 require_relative 'contrib/shoryuken/integration'

lib/datadog/tracing/contrib/roda/configuration/settings.rb

@@ -0,0 +1,34 @@
+# frozen_string_literal: true
+
+require_relative '../../configuration/settings'
+require_relative '../ext'
+
+module Datadog
+  module Tracing
+    module Contrib
+      module Roda
+        module Configuration
+          # Custom settings for the Roda integration
+          class Settings < Contrib::Configuration::Settings
+            option :enabled do |o|
+              o.default { env_to_bool(Ext::ENV_ENABLED, true) }
+              o.lazy
+            end
+
+            option :analytics_enabled do |o|
+              o.default { env_to_bool(Ext::ENV_ANALYTICS_ENABLED, false) }
+              o.lazy
+            end
+
+            option :analytics_sample_rate do |o|
+              o.default { env_to_float(Ext::ENV_ANALYTICS_SAMPLE_RATE, 1.0) }
+              o.lazy
+            end
+
+            option :service_name
+          end
+        end
+      end
+    end
+  end
+end

lib/datadog/tracing/contrib/roda/ext.rb

@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Datadog
+  module Tracing
+    module Contrib
+      module Roda
+        # Roda integration constants
+        module Ext
+          APP = 'roda'
+          ENV_ENABLED = 'DD_TRACE_RODA_ENABLED'
+          ENV_ANALYTICS_ENABLED = 'DD_RODA_ANALYTICS_ENABLED'
+          ENV_ANALYTICS_SAMPLE_RATE = 'DD_RODA_ANALYTICS_SAMPLE_RATE'
+          SPAN_REQUEST = 'roda.request'
+        end
+      end
+    end
+  end
+end

lib/datadog/tracing/contrib/roda/instrumentation.rb

@@ -0,0 +1,76 @@
+# frozen_string_literal: true
+
+require_relative '../../metadata/ext'
+require_relative 'ext'
+require_relative '../analytics'
+
+module Datadog
+  module Tracing
+    module Contrib
+      module Roda
+        # Instrumentation for Roda
+        module Instrumentation
+          def _roda_handle_main_route
+            instrument(Ext::SPAN_REQUEST) { super }
+          end
+
+          def call
+            instrument(Ext::SPAN_REQUEST) { super }
+          end
+
+          private
+
+          def instrument(span_name, &block)
+            Tracing.trace(span_name) do |span|
+              begin
+                request_method = request.request_method.to_s.upcase
+
+                span.service = configuration[:service_name] if configuration[:service_name]
+
+                span.span_type = Tracing::Metadata::Ext::HTTP::TYPE_INBOUND
+
+                # Using the http method as a resource, since the URL/path can trigger
+                # a possibly infinite number of resources.
+                span.resource = request_method
+
+                span.set_tag(Tracing::Metadata::Ext::HTTP::TAG_URL, request.path)
+                span.set_tag(Tracing::Metadata::Ext::HTTP::TAG_METHOD, request_method)
+
+                # Add analytics tag to the span
+                if Contrib::Analytics.enabled?(configuration[:analytics_enabled])
+                  Contrib::Analytics.set_sample_rate(span, configuration[:analytics_sample_rate])
+                end
+
+                # Measure service stats
+                Contrib::Analytics.set_measured(span)
+              ensure
+                begin
+                  response = yield
+                rescue StandardError
+                  # The status code is unknown to Roda and decided by the upstream web runner.
+                  # In this case, spans default to status code 500 rather than a blank status code.
+                  default_error_status = '500'
+                  span.resource = "#{request_method} #{default_error_status}"
+                  span.set_tag(Tracing::Metadata::Ext::HTTP::TAG_STATUS_CODE, default_error_status)
+                  raise
+                end
+              end
+
+              status_code = response[0]
+
+              # Adds status code to the resource name once the resource comes back
+              span.resource = "#{request_method} #{status_code}"
+              span.set_tag(Tracing::Metadata::Ext::HTTP::TAG_STATUS_CODE, status_code)
+              span.status = 1 if status_code.to_s.start_with?('5')
+              response
+            end
+          end
+
+          def configuration
+            Datadog.configuration.tracing[:roda]
+          end
+        end
+      end
+    end
+  end
+end

lib/datadog/tracing/contrib/roda/integration.rb

@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+
+# typed: false
+
+require_relative '../integration'
+require_relative 'configuration/settings'
+require_relative 'patcher'
+
+module Datadog
+  module Tracing
+    module Contrib
+      module Roda
+        # Description of Roda integration
+        class Integration
+          include Contrib::Integration
+
+          MINIMUM_VERSION = Gem::Version.new('2.0.0')
+          MAXIMUM_VERSION = Gem::Version.new('4.0.0')
+
+          register_as :roda
+
+          def self.version
+            Gem.loaded_specs['roda'] && Gem.loaded_specs['roda'].version
+          end
+
+          def self.loaded?
+            !defined?(::Roda).nil?
+          end
+
+          def self.compatible?
+            super && version >= MINIMUM_VERSION && version < MAXIMUM_VERSION
+          end
+
+          def new_configuration
+            Configuration::Settings.new
+          end
+
+          def patcher
+            Patcher
+          end
+        end
+      end
+    end
+  end
+end

lib/datadog/tracing/contrib/roda/patcher.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+# typed: ignore
+
+require_relative 'patcher'
+require_relative 'ext'
+require_relative 'instrumentation'
+
+module Datadog
+  module Tracing
+    module Contrib
+      module Roda
+        # Patcher enables patching of 'roda'
+        module Patcher
+          include Contrib::Patcher
+
+          module_function
+
+          def target_version
+            Integration.version
+          end
+
+          def patch
+            ::Roda.prepend(Instrumentation)
+          end
+        end
+      end
+    end
+  end
+end

spec/datadog/tracing/contrib/roda/instrumentation_spec.rb

@@ -0,0 +1,61 @@
+# typed: false
+
+require_relative './shared_examples'
+require 'roda'
+require 'ddtrace'
+require 'datadog/tracing/contrib/roda/instrumentation'
+require 'datadog/tracing/contrib/roda/ext'
+require 'datadog/tracing/contrib/support/spec_helper'
+require 'datadog/tracing/contrib/support/tracer_helpers'
+
+RSpec.describe Datadog::Tracing::Contrib::Roda::Instrumentation do
+  describe 'when implemented in Roda' do
+    let(:configuration_options) { {} }
+
+    before do
+      Datadog.configure do |c|
+        c.tracing.instrument :roda, configuration_options
+      end
+    end
+
+    after do
+      Datadog.registry[:roda].reset_configuration!
+    end
+
+    describe 'When using automatic instrumentation' do
+      let(:env) { { REQUEST_METHOD: 'GET' } }
+      context 'configuring roda' do
+        context 'with default settings' do
+          it 'enables the tracer' do
+            expect(Datadog.configuration.tracing.enabled).to eq(true)
+          end
+
+          it 'does not have a default service name (left up to global configuration)' do
+            expect(Datadog.configuration.tracing[:roda].service_name).to eq(nil)
+            expect(Datadog.configuration.service).to eq('rspec')
+          end
+
+          context 'with a custom service name' do
+            let(:custom_service_name) { 'custom_service_name' }
+            let(:configuration_options) { { service_name: custom_service_name } }
+
+            it 'sets a custom service name' do
+              expect(Datadog.configuration.service).to eq('rspec')
+              expect(Datadog.configuration.tracing[:roda].service_name).to eq(custom_service_name)
+            end
+          end
+        end
+      end
+    end
+
+    describe 'when application calls on the instrumented method' do
+      context 'using #call' do
+        it_behaves_like 'shared examples for roda', :call
+      end
+
+      context 'using #_roda_handle_main_route' do
+        it_behaves_like 'shared examples for roda', :_roda_handle_main_route
+      end
+    end
+  end
+end