Shoryuken middleware tracer

lib/ddtrace/contrib/shoryuken/tracer.rb

@@ -0,0 +1,73 @@
+module Datadog
+  module Contrib
+    module Shoryuken
+      # Tracer is a Shoryuken server-side middleware which traces executed jobs
+      class Tracer
+        DEFAULT_CONFIG = {
+          enabled: true,
+          shoryuken_service: 'shoryuken',
+          tracer: Datadog.tracer,
+          debug: false,
+          trace_agent_hostname: Datadog::Writer::HOSTNAME,
+          trace_agent_port: Datadog::Writer::PORT
+        }.freeze
+
+        def initialize(options = {})
+          # check if Rails configuration is available and use it to override
+          # Shoryuken defaults
+          rails_config = ::Rails.configuration.datadog_trace rescue {}
+          base_config = DEFAULT_CONFIG.merge(rails_config)
+          user_config = base_config.merge(options)
+          @tracer = user_config[:tracer]
+          @shoryuken_service = user_config[:shoryuken_service]
+
+          # set Tracer status
+          @tracer.enabled = user_config[:enabled]
+          Datadog::Tracer.debug_logging = user_config[:debug]
+
+          # configure the Tracer instance
+          @tracer.configure(
+            hostname: user_config[:trace_agent_hostname],
+            port: user_config[:trace_agent_port]
+          )
+        end
+
+        def call(worker_instance, queue, sqs_msg, body)
+          # If class is wrapping something else, the interesting resource info
+          # is the underlying, wrapped class, and not the wrapper.
+
+          # configure Shoryuken service
+          tracer_info = { resource: worker_instance.class.name }
+          if worker_instance.class.name.ends_with?('ShoryukenAdapter::JobWrapper')
+            tracer_info[:job_id] = body['job_id'] || body[:job_id]
+            tracer_info[:resource] = body['job_class'] || body[:job_class]
+            tracer_info[:wrapped] = true
+          else
+            tracer_info[:job_id] = worker_instance.job_id
+          end
+          set_service_info(@shoryuken_service)
+
+          @tracer.trace('shoryuken.job', service: @shoryuken_service, span_type: 'job') do |span|
+            span.resource = tracer_info[:resource]
+            span.set_tag('shoryuken.job.id', tracer_info[:job_id])
+            span.set_tag('shoryuken.job.queue', queue)
+            span.set_tag('shoryuken.job.wrapped', 'true') if tracer_info[:wrapped]
+
+            yield
+          end
+        end
+
+        private
+
+        def set_service_info(service)
+          return if @tracer.services[service]
+          @tracer.set_service_info(
+            service,
+            'shoryuken',
+            Datadog::Ext::AppTypes::WORKER
+          )
+        end
+      end
+    end
+  end
+end