roboservant

Automatically fuzz your servant apis in a contextually-aware way.

why?

Servant gives us a lot of information about what a server can do. We use this information to generate arbitrarily long request/response sessions and verify properties that should hold over them.

why not servant-quickcheck?

servant-quickcheck is a great package and I've learned a lot from it. Unfortunately, there's a lot of the state space it can't explore: modern webapps are full of pointer-like structures, whether they're URLs or database keys/uuids. servant-quickcheck demands that you be able to generate these without context via Arbitrary: good luck exploring an API that requires you to generate just the right UUID to hit non-trivial code.

roboservant avoids this by using quickcheck-state-machine, which models the dynamic state in such a way that we can use results of previous calls.