Rely on Rack semconv middlware alias for Sinatra instrumentation

Author: hannahramadan

instrumentation/CONTRIBUTING.md

@@ -458,11 +458,8 @@ end
 # Set up fake Rack application
 builder = Rack::Builder.app do
   # Integration is automatic in web frameworks but plain Rack applications require this line.
-  # - middleware_args_old to emit old HTTP semantic conventions
-  # - middleware_args_stable to emit stable HTTP semantic conventions
-  # - middleware_args_dup to emit both old and stable HTTP semantic conventions
   # Enable it in your config.ru.
-  use *OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args_old
+  use *OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args
   run ExampleAPI
 end
 app = Rack::MockRequest.new(builder)

instrumentation/rack/lib/opentelemetry/instrumentation/rack/instrumentation.rb

@@ -36,19 +36,19 @@ class Instrumentation < OpenTelemetry::Instrumentation::Base
         #
         # @example Default usage
         #   Rack::Builder.new do
-        #     use *OpenTelemetry::Instrumentation::Rack::Instrumenation.instance.middleware_args_old
+        #     use *OpenTelemetry::Instrumentation::Rack::Instrumenation.instance.middleware_args
         #     run lambda { |_arg| [200, { 'Content-Type' => 'text/plain' }, body] }
         #   end
         # @return [Array] consisting of a middleware and arguments used in rack builders
-        def middleware_args_old
+        def middleware_args
           if config.fetch(:use_rack_events, false) == true && defined?(OpenTelemetry::Instrumentation::Rack::Middlewares::Old::EventHandler)
             [::Rack::Events, [OpenTelemetry::Instrumentation::Rack::Middlewares::Old::EventHandler.new]]
           else
             [OpenTelemetry::Instrumentation::Rack::Middlewares::Old::TracerMiddleware]
           end
         end
 
-        alias middleware_args middleware_args_old
+        alias middleware_args_old middleware_args
 
         def middleware_args_dup
           if config.fetch(:use_rack_events, false) == true && defined?(OpenTelemetry::Instrumentation::Rack::Middlewares::Dup::EventHandler)

instrumentation/sinatra/example/config.ru

@@ -47,9 +47,5 @@ class App < Sinatra::Base
   end
 end
 
-# Rack instrumentation is moving through the process of migrating to the new HTTP semantic
-# conventions. In this example, we will use the old HTTP conventions by patching the Rack
-# middleware that uses the old conventions. See README: HTTP Semantic Conventions for more
-# information.
-use(*OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args_old)
+use(*OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args)
 run App

instrumentation/sinatra/lib/opentelemetry/instrumentation/sinatra/instrumentation.rb

@@ -60,7 +60,7 @@ def install_middleware(app)
             elsif values.include?('http')
               app.use(*OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args_stable)
             else
-              app.use(*OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args_old)
+              app.use(*OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args)
             end
           end
 

instrumentation/sinatra/test/opentelemetry/instrumentation/sinatra_old_http_test.rb

@@ -198,7 +198,7 @@ class CustomError < StandardError; end
       let(:app) do
         apps_to_build = apps
         Rack::Builder.new do
-          use(*OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args_old)
+          use(*OpenTelemetry::Instrumentation::Rack::Instrumentation.instance.middleware_args)
 
           apps_to_build.each do |root, app|
             map root do