only set otel.service.name from application_name if not set in credentials

Author: breedx-splk

lib/java_buildpack/framework/splunk_otel_java_agent.rb

@@ -40,6 +40,9 @@ def release
           java_opts.add_system_property(key, value) if key.start_with?('splunk.') || key.start_with?('otel.')
         end
 
+        # Set the otel.service.name to the application_name if not specified in credentials
+        return if credentials.key? 'otel.service.name'
+
         app_name = @application.details['application_name']
         java_opts.add_system_property('otel.service.name', app_name)
       end
@@ -51,6 +54,7 @@ def supports?
         @application.services.one_service? REQUIRED_SERVICE_NAME_FILTER
       end
 
+      # bound service must contain the string `splunk-o11y`
       REQUIRED_SERVICE_NAME_FILTER = /splunk-o11y/.freeze
 
     end

spec/java_buildpack/framework/splunk_otel_java_agent_spec.rb

@@ -62,13 +62,21 @@
 
     it 'sets the service name from the application name' do
       allow(services).to receive(:find_service).and_return('credentials' => { 'splunk.access.token' => 'sekret' })
-      # allow(details).to be( { 'application_name' => 'dick' })
 
       component.release
 
       expect(java_opts).to include('-Dotel.service.name=GreatServiceTM')
     end
 
+    it 'prefers credentials over application_name for service name' do
+      creds = { 'credentials' => { 'otel.service.name' => 'sweet', 'splunk.access.token' => 'sekret' } }
+      allow(services).to receive(:find_service).and_return(creds)
+
+      component.release
+
+      expect(java_opts).to include('-Dotel.service.name=sweet')
+    end
+
   end
 
 end