refactor decode proof to extract all keys

[ermalkaleci]

this will make it easy to implement new inherent #561 decode_proof will find all possible keys so there's no need to inject unchanged ones

[ermalkaleci]

setValidationData is executed first so other inherent can read proofs from query.parachainSystem.relayStateProof() @girazoki

[girazoki]

thank you!

[girazoki]

@ermalkaleci as I am understanding it, now every key that was proven from the previous block and that is not modified will be included and proved on the new built block?

[ermalkaleci]

yes, you don't need to touch SetValidationData inherent. SetValidationData will be executed first and set new proofs which you can read on your inherent from query.parachainSystem.relayStateProof()

[girazoki]

ah that's amazing. I think it does cover most of our needs so we will shortly propose a PR adding tanssi support. The only thing I am thinking is: what happens if there are some keys being proved in one inherent (set-validation-data) and others in another inherent (authorities-noting in our case) in production? Probably the nibbles passed to set-validation-data do not include all keys to be able to fork correctly.

We might propose the possibility to add additional keys to set-validation-data inherent if that's fine in the PR that supports tanssi (in other words, being able to add additional keys to the WellKnownKeys struct)

[girazoki]

the other thing we can do is refactor our node to inject a single proof (in set-validation-data) that contains all keys we need to prove. That should work with this implementation and I think its cleaner! So in that case you dont need to worry about what I just said :)

[ermalkaleci]

I think I was wrong. I will look again tomorrow, maybe it needs a refactor