How to I get the Haskell data value from the request body in Snap framework

Question

I am new Snap and Haskell web development, I want to parse the request body to Haskell data value .

I have tried the example from this https://github.com/raimohanska/snap-skeleton/blob/master/src/Examples/Restful.hs . It seems to work , But wondering if there is any standard way to do this in Snap world .