I've started trying to test ETSDB with Common Test and found that it wasn't terribly straightforward to test the Riak Core vnode. The vnode is managed by a Riak Core gen_fsm and isn't a built-in OTP behavior.

I wanted to include the Riak Core gen_fsm to make sure that I integrated it properly. First you want to spin up the riak_core_vnode with your vnode implementation and save the config in the Pid.

Similarly to tear it down you should send a message to stop the FSM. This requires a tear down call and adding a handler in your vnode to return a stop.

That includes the send_command which is a variation from the Riak Core source. It will handle sending the message in a way that can get the response sent back to the sending process. Riak Core does some mucking around to deal with running with the full application.

Now you can call send_command with the Pid of the FSM and with the ref returned can pull that messages out of the mailbox!