if you ever happen to create SOAP ui mock serice I am sure you had requirment to log certain parameters or entire requiest to see whats being posted to your mock service. it is very easy. this is how you can do that.
double click on your service (from left hand panel)
select onRequest tab
add below script
Restart your service.
Now you can see logs are being printed with your request body.
if you don’t know how you can create mock service using soapUI you can refer this video