test+ci: Test with Rack 3.x

.circleci/config.yml

@@ -316,6 +316,7 @@ workflows:
                 - "./gemfiles/net_http_01.gemfile"
                 - "./gemfiles/rack_16.gemfile"
                 - "./gemfiles/rack_20.gemfile"
+                - "./gemfiles/rack_30.gemfile"
                 - "./gemfiles/redis_40.gemfile"
                 - "./gemfiles/rest_client_16.gemfile"
                 - "./gemfiles/rest_client_20.gemfile"

gemfiles/rack_30.gemfile

@@ -0,0 +1,16 @@
+# (c) Copyright IBM Corp. 2023
+
+source "https://rubygems.org"
+
+gem "rake"
+gem "minitest", "5.9.1"
+gem "minitest-reporters"
+gem "webmock"
+gem "puma"
+gem "rubocop", "~> 1.9"
+gem "rack-test"
+gem "simplecov", "~> 0.21.2"
+gem "rack", ">= 3.0.8"
+gem "rackup", ">= 2.1.0"
+
+gemspec path: "../"

test/instrumentation/rack_test.rb

@@ -3,7 +3,13 @@
 
 require 'test_helper'
 require 'rack/test'
-require 'rack/lobster'
+
+framework_version = Gem::Specification.find_by_name('rack').version
+if framework_version < Gem::Version.new('3.0.0')
+  require 'rack/lobster'
+else
+  require 'rackup/lobster'
+end
 
 class RackTest < Minitest::Test
   include Rack::Test::Methods
@@ -34,11 +40,16 @@ def call(_env)
   end
 
   def app
+    framework_version = Gem::Specification.find_by_name('rack').version
     @app = Rack::Builder.new do
       use Rack::CommonLogger
       use Rack::ShowExceptions
       use Instana::Rack
-      map("/mrlobster") { run Rack::Lobster.new }
+      if framework_version < Gem::Version.new('3.0.0')
+        map("/mrlobster") { run Rack::Lobster.new }
+      else
+        map("/mrlobster") { run Rackup::Lobster.new }
+      end
       map("/path_tpl") { run PathTemplateApp.new }
       map("/error") { run ErrorApp.new }
       map("/five_zero_one") { run FiveZeroOneApp.new }