Allow deploy native contracts in any block (only once)

[shargon]

Close #2055

[erikzhang]

I prefer to use System.Contract.Create.

And how do onPersist() and postPersist() work?

[Qiao-Jin]

I think logic of onPersistScript and postPersistScript should also be changed.
Besides, do we need some checks, i.e. CheckCommittee for Neo_Native_Deploy?

[shargon]

I prefer to use System.Contract.Create.

Remove Neo_Native_Deploy and generate a native NEFFile?
On persist logic can be changed, but it's easy to do a conditional. if (height > X) onPersist=...

[erikzhang]

Remove Neo_Native_Deploy and generate a native NEFFile?

Yes. But let's wait for #2044.

[Tommo-L]

Ping

We need to merge this pr in preview4.

[shargon]

@Tommo-L We need #2044 I will move the code to onPersist

[shargon]

Ready to review again

[Tommo-L]

Remove Neo_Native_Deploy and generate a native NEFFile?

Yes. But let's wait for #2044.

@shargon miss nef file?

[Tommo-L]

Remove Neo_Native_Deploy and generate a native NEFFile?

If so, we should add Update/Destroy methods in native contract.

[shargon]

OnPersist has no Tx, and the hash it's related to the sender, so we can't use Contract.Create like this...

[Tommo-L]

OnPersist has no Tx, and the hash it's related to the sender, so we can't use Contract.Create like this...

I think we don't need to deploy it in OnPersis. If we use Contract.Create, just execute the tx.script is enough.

[shargon]

@Tommo-L Then we need GAS in the deploy transaction, and the sender has no gas....

[Tommo-L]

@Tommo-L Then we need GAS in the deploy transaction, and the sender has no gas....

No need to charge for the txs in genesis block.

[erikzhang]

If so, we should add Update/Destroy methods in native contract.

Why do we need Update/Destroy?

[Tommo-L]

If so, we should add Update/Destroy methods in native contract.

Why do we need Update/Destroy?

Just like a normal contract upgrade, we don't have to worry about the impact of the state, due to the native contract upgrade.

[erikzhang]

But the code is not in the script. It is in the native code.

[Tommo-L]

Do we need Neo.Native.Update ? How do we update native contract?

[shargon]

I think that we should do a condition inside the method, and change the method hash in order to include the arguments, in this way we can have method overloads (or just use other name).

[roman-khimov]

I think this can be simplified by using the following model:

• every native contract has an onPersist method
• onPersistScript invokes all of them (iterating over NativeContract.Contracts, in their natural ID-based order)
• in onPersist handler native contract can check for PersistingBlock.Index == 0 (or any other block number where this contract should be activated) and deploy itself if needed

This:

• allows to avoid if block.Index ... logic in Persist (think of new contracts added and new branches there), moving it to specific contracts
• allows for contract to actually destroy itself if needed at certain height
• follows OnPersist semantics for native contracts #1913
• allows for Contract to manage contracts #2000 (contract-managing contract will be the first one to execute in genesis onPersist, so it can deploy itself using internal methods and make it possible for other contracts to use its public methods afterwards)

[erikzhang]

Please check #2119