[EPIC] Execution API

[gupadhyaya]

Rollkit currently supports ABCI 2.0 (execution.go) for execution. This work will expand rollkit to support different execution engines by defining a common execution interface (via go-execution) which can be implemented by different execution engines such as ABCI (go-execution-abci), EVM (go-execution-evm), etc.

Details:

• The execution interface (go-execution) can support GRPC (similar to go-sequencing and go-da)
• The interface itself can be inspired by other works such as astria's execution api, omni's octane, berachain's beaconkit, and many more.
• The exact methods in the interface still needs to be determined. But, astria's reference is here.

Tasks

• Create go-execution repo with ABCI 2.0 methods as interface to begin with.
• Add grpc proxy and dummy execution implementation along with tests go-execution repo
• Create go-execution-abci and refactor code from rollkit's execution.go to this repo
• Refactor rollkit to use go-execution interface and go-execution-abci implementation via grpc endpoint
• https://github.com/gupadhyaya/go-execution-evm

---

Execution API

go-execution

• Define Go interface go-execution#10
• Write comprehensive go-doc go-execution#11
• Create gRPC proxy client and server implementation go-execution#12
• Define sentinel errors go-execution#17
• Remove JSON-RPC proxy go-execution#34

Testing

• Create mock using mockery go-execution#13
• Create dummy implmementation of Execution API go-execution#14
• Create reusable test suite go-execution#15
  • Implement smoke tests go-execution#16
• Improve dummy implementation go-execution#24
• Use contexts with timeouts in tests go-execution#33

go-execution-evm

• Create/move repository
• Setup repository
• Establish EVM connection using engine API go-execution-evm#1
• Create empty implementation of go-execution API go-execution-evm#2
• Implement InitChain method go-execution-evm#3
• Implement GetTxs method go-execution-evm#4
• Implement ExecuteTxs method go-execution-evm#5
• Implement SetFinal method go-execution-evm#6
• Create binary go-execution-evm#12
• refactor: move eth and engine client Dial to start method go-execution-evm#17

Testing

• Setup automated testing go-execution-evm#7
• Run reusable test suite from go-execution go-execution-evm#8
• Implementation-specific unit tests go-execution-evm#9
• test: generate JWT token in tests go-execution-evm#15
• ci: resolve docker client/server compatibility issue go-execution-evm#18

go-execution-cosmos-sdk

• Implement InitChain
• Implement GetTxs
  • Re-import latest ABCI mempool implementation from cometbft
• Implement ExecuteTxs
• Implement SetFinal
• Implement cometbft APIs
  • Identify what has to be exposed from rollkit via RPC

Testing

• Setup automated testing
• Run reusable test suite from go-execution
• Implementation-specific unit tests

rollkit

• Refactor Node interface #1896
• Clean up FullNode #1897
• Remove FullClient #1898
• Clean up LightNode #1899
• Remove LightClient #1900
• Cleanup Store #1901
• Refactor or rewrite block.Manager #1902
• Implement equivalent of BaseService #1903
• Remove mempool #1904
• Remove existing RPCs #1905
• Cleanup config package #1906
• Cleanup proto directory #1907
• [EPIC] Remove cometbft dependencies #1125
• Update run node command #1908
• New genesis handling #1909
• docs: Create ADR describing Execution API #1931

Testing

• Figure out: re-use vs re-write integration tests

The list above may get outdated; please check the Exec API project board for reference.

[Manav-Aggarwal]

Relevant: https://github.com/gakonst/narwhal-abci-evm

[gupadhyaya]

Execution APIs for consensus client (e.g., rollkit) to interact with execution client (ABCI 2.0 or EVM):

// InitChain is used by the consensus client and execution client to sync
// genesisTime is the genesis time for the chain
// initialHeight is the initial height of the chain
// chainId is the chain id
// stateRoot is the genesis state root
// maxBytes is the maximum bytes that the execution client can allow
InitChain(
     genesisTime time.Time, 
     initialHeight uint, 
     chainId []byte
) (
     stateRoot Hash, 
     maxBytes uint, 
     err error
)

// GetTxs is used by the consensus client (rollkit) to fetch all available transactions from the execution client's mempool.
GetTxs() []Tx

// ExecuteTxs informs the execution client to execute transactions
// blockHeight is the height to be used to produce block/header
// timestamp is the timestamp to be used in the block/header
// prevStateRoot is the previous block hash to create the next block/header
// updatedStateRoot is the updated state root hash
// maxBytes is the maximum bytes that the execution client can allow
ExecuteTxs(
     txs []Tx, 
     blockHeight int, 
     timestamp time.Time, 
     prevStateRoot Hash
) (
     updatedStateRoot Hash, 
     maxBytes uint, 
     err error
)

// SetFinal marks a block as final
SetFinal(
     blockHeight uint
) error

Apart from the APIs, the components related to execution will be refactored away from the consensus client (rollkit) and moved to respective execution client repositories. For example, the mempool, the rpc, the state/storage, and indexers.

The execution client will also establish a direct grpc connection to the consensus client (rollkit) for querying consensus related information. e.g., node info, node status, p2p info, etc.

[gupadhyaya]

Execution API using ABCI 2.0:

InitChain => InitChain

GetTxs => no direct API, but can map to reaping from the mempool

ExecuteTxs => PrepareProposal -> ProcessProposal -> FinalizeBlock -> Commit

SetFinal => no direct API, but can map to an RPC endpoint

Execution API using Engine API:

InitChain => engine_forkchoiceUpdated

GetTxs => no direct API, but can map to reaping from mempool

ExecuteTxs => engine_newPayload, engine_getPayload

SetFinal => engine_forkchoiceUpdated

[Manav-Aggarwal]

Instead of a list of Txs: txs []Tx, we should change it to a single de-serializable bytes object in ExecuteTxs:

ExecuteTxs(
     blockRequest []byte, 
     blockHeight int, 
     timestamp time.Time, 
     prevStateRoot Hash
) (
     updatedStateRoot Hash, 
     maxBytes uint, 
     err error
)

[Manav-Aggarwal]