fix: Support Active Jobs with keyword args across ruby versions (#852)

* Make active_job instrumentation compatible with jobs defined with keywords

* Add addional arg types for activejob tests

Author: kjg

instrumentation/active_job/lib/opentelemetry/instrumentation/active_job/patches/base.rb

@@ -20,6 +20,7 @@ def initialize(*args)
             @metadata = {}
             super
           end
+          ruby2_keywords(:initialize) if respond_to?(:ruby2_keywords, true)
 
           def serialize
             super.merge('metadata' => serialize_arguments(metadata))

instrumentation/active_job/test/instrumentation/active_job/patches/active_job_callbacks_test.rb

@@ -46,6 +46,20 @@
     end
   end
 
+  describe 'compatibility' do
+    it 'works with positional args' do
+      _(PositionalOnlyArgsJob.perform_now('arg1')).must_be_nil # Make sure this runs without raising an error
+    end
+
+    it 'works with keyword args' do
+      _(KeywordOnlyArgsJob.perform_now(keyword2: :keyword2)).must_be_nil # Make sure this runs without raising an error
+    end
+
+    it 'works with mixed args' do
+      _(MixedArgsJob.perform_now('arg1', 'arg2', keyword2: :keyword2)).must_be_nil # Make sure this runs without raising an error
+    end
+  end
+
   describe 'exception handling' do
     it 'sets span status to error' do
       _ { ExceptionJob.perform_now }.must_raise StandardError, 'This job raises an exception'

instrumentation/active_job/test/test_helper.rb

@@ -37,6 +37,17 @@ def perform
   end
 end
 
+class PositionalOnlyArgsJob < ::ActiveJob::Base
+  def perform(arg1, arg2 = 'default'); end
+end
+class KeywordOnlyArgsJob < ::ActiveJob::Base
+  def perform(keyword1: 'default', keyword2:); end
+end
+
+class MixedArgsJob < ::ActiveJob::Base
+  def perform(arg1, arg2, keyword1: 'default', keyword2:); end
+end
+
 ::ActiveJob::Base.queue_adapter = :inline
 ::ActiveJob::Base.logger = Logger.new(File::NULL)