There are scenarios where invalid JSON request may be received by Service REST. Is there any OOTB feature which will enable us to Log these errors ?. The service activity will be called only if the request is processed successfully. How to handle invalid JSON errors.
You can log request in exception scenario as well using Log level settings. Change servicehelper log level settings to ALL then you will see all request getting logged to logs. Also REST service rule, you have option to respond in case of Mapping error where you can give response to consumer.