StateTransition JSON/Codec

[sourabhniyogi]

We request a W3F Codec test vector for state transitions, which can be simply a composition of a pre and post state snapshot (as many test vectors contain, but the raw k,v data) and a block (done already):

Our suggestion is this (in Go form)

type StateTransition struct {
	PreState  StateSnapshotRaw `json:"pre_state"`
	Block     Block            `json:"block"`
	PostState StateSnapshotRaw `json:"post_state"`
}

type StateSnapshotRaw struct {
	StateRoot common.Hash `json:"state_root"`
	KeyVals   KeyVals     `json:"keyvals"`
}

type KeyVals []KeyVal
type KeyVal [2][]byte

and included stateroot. But we think it would be useful to improve the service metadata, which was brought in recently.

We have assembled some state_transitions here in a public repo:

• fallback
• safrole
• assurances