Update rollapp state

[liorzilp]

Overview

When a sequencer is attached to a rollapp it can start to serve the rollapp chain and publish state updates. Create a UpdateState transaction.

Update State Message

Block description object:

• height: is the height of the block.
• stateRoot: is the state root of the block.
• intermediateStatesRoot: is the root of a Merkle tree built from the ISRs of the block (Intermediate State Root).

The following fields are required for updating a state:

• creator: is the bech32-encoded address of the sequencer account sent the transaction.
• rollappId: is the rollapp that the sequencer belongs to and asking to update
• startHigh: is the block height of the first block in the batch.
• numBlocks: is the number of blocks included in this batch update.
• DApath: is the description of the location on the DA layer.
• version: is the version of the rollapp.
• lastBD: the latest block descriptor of the last state update.
• BDs: is a list of block description objects (one per block). the list must be ordered by height, start from startHeight to startHeight+numBlocks

State in store

StateInfo object:

• sequencer: is the bech32-encoded address of the sequencer account sent the transaction.
• rollappId: is the rollapp that the sequencer belongs to and asking to update
• startHeight: is the block height of the first block in the batch.
• numBlocks: is the number of blocks included in this batch update.
• DApath: is the description of the location on the DA layer.
• version: is the version of the rollapp.
• BDs: is a list of block description objects (one per block). the list must be ordered by height, starting from startHeight to startHeight+numBlocks-1

• additional:

• creationHeight: is the height at which the UpdateState took place
• status: is the status of the state update (see Rollapp states' status #49)

Validations

Basic validations

1. blockDescriptors list size should be equal to numBlocks -> ErrInvalidNumBlocks
2. blockDescriptors should contain all the high start from startHeight to (startHeight+numBlocks-1) in increasing order -> ErrInvalidBlockSequence
3. blockDescriptors startHeight should be equal to lastBlockDescriptor.high+1

Stateful validation

1. The rollapp exists -> ErrUnknownRollappId
2. The sequencer is registered (can retrieve the rollapp object) -> ErrUnknownSequencer
3. The rollappId is the rollappId that the sequencer belongs to -> ErrSequencerRollappMismatch
4. Version is the currently active version of the rollapp -> ErrVersionMismatch
5. If the rollapp has PermissionedAddress list, check that the sequencer is in list -> ErrLogic
6. The StartHeight should be the latest+1 -> ErrWrongBlockHeight
7. Only one update per rollapp is eligible in a block ->ErrMultiUpdateStateInBlock

Basic flow

Sending a transaction

1. Sequencer can send a transaction for updating a batch
2. If it is the first state update:
   • the lastBlockDescriptor.high should be zero
   • str&isrRoot are ignored
   • the start version is 0

Queries

1. Retrieving the latest state update by rollapp

[liorzilp]

Removing lastBD as we can check the lastest state from store