post-merge Bellatrix block proposals (#3570)

* post-merge Bellatrix block proposals

* tolerate running without an Eth1Monitor better

* remove obsolete comment

* use correct empty receipts root

* handle invalid CLI parameters in parseCmdArg overloads

beacon_chain/conf.nim

@@ -513,6 +513,13 @@ type
         defaultValue: 128
         name: "safe-slots-to-import-optimistically" }: uint64
 
+      # Same option as appears in Lighthouse and Prysm
+      # https://lighthouse-book.sigmaprime.io/suggested-fee-recipient.html
+      # https://github.com/prysmaticlabs/prysm/pull/10312
+      suggestedFeeRecipient* {.
+        desc: "Suggested fee recipient"
+        name: "suggested-fee-recipient" .}: Option[Address]
+
     of BNStartUpCmd.createTestnet:
       testnetDepositsFile* {.
         desc: "A LaunchPad deposits file for the genesis state validators"
@@ -1099,6 +1106,13 @@ proc readValue*(r: var TomlReader, a: var WalletName)
   except CatchableError:
     r.raiseUnexpectedValue("string expected")
 
+proc readValue*(r: var TomlReader, a: var Address)
+               {.raises: [Defect, IOError, SerializationError].} =
+  try:
+    a = parseCmdArg(Address, r.readValue(string))
+  except CatchableError:
+    r.raiseUnexpectedValue("string expected")
+
 proc loadEth2Network*(config: BeaconNodeConf): Eth2NetworkMetadata {.raises: [Defect, IOError].} =
   network_name.set(2, labelValues = [config.eth2Network.get(otherwise = "mainnet")])
   when not defined(gnosisChainBinary):

beacon_chain/eth1/eth1_monitor.nim

@@ -1022,7 +1022,7 @@ proc doStop(m: Eth1Monitor) {.async.} =
     m.dataProvider = nil
 
 proc ensureDataProvider*(m: Eth1Monitor) {.async.} =
-  if not m.dataProvider.isNil:
+  if m.isNil or not m.dataProvider.isNil:
     return
 
   let web3Url = m.web3Urls[m.startIdx mod m.web3Urls.len]

beacon_chain/gossip_processing/block_processor.nim

@@ -376,6 +376,10 @@ proc newExecutionPayload*(
       UInt256.fromBytesLE(executionPayload.base_fee_per_gas.data),
     numTransactions = executionPayload.transactions.len
 
+  if eth1Monitor.isNil:
+    info "newPayload: attempting to process execution payload without an Eth1Monitor. Ensure --web3-url setting is correct."
+    return PayloadExecutionStatus.syncing
+
   try:
     let
       payloadResponse =
@@ -383,7 +387,7 @@ proc newExecutionPayload*(
             eth1Monitor.newPayload(
               executionPayload.asEngineExecutionPayload),
             web3Timeout):
-          debug "newPayload: newPayload timed out"
+          info "newPayload: newPayload timed out"
           PayloadStatusV1(status: PayloadExecutionStatus.syncing)
       payloadStatus = payloadResponse.status
 
@@ -432,7 +436,7 @@ proc runQueueProcessingLoop*(self: ref BlockProcessor) {.async.} =
               self.consensusManager.eth1Monitor,
               blck.blck.bellatrixData.message.body.execution_payload)
           except CatchableError as err:
-            debug "runQueueProcessingLoop: newExecutionPayload failed",
+            debug "runQueueProcessingLoop: newPayload failed",
               err = err.msg
             PayloadExecutionStatus.syncing
         else:
@@ -502,14 +506,6 @@ proc runQueueProcessingLoop*(self: ref BlockProcessor) {.async.} =
 
     if  executionPayloadStatus == PayloadExecutionStatus.valid and
         hasExecutionPayload:
-      let
+      await self.runForkchoiceUpdated(
-        headBlockRoot = self.consensusManager.dag.head.executionBlockRoot
+        self.consensusManager.dag.head.executionBlockRoot,
-
+        self.consensusManager.dag.finalizedHead.blck.executionBlockRoot)
-        finalizedBlockRoot =
-          if not isZero(
-              self.consensusManager.dag.finalizedHead.blck.executionBlockRoot):
-            self.consensusManager.dag.finalizedHead.blck.executionBlockRoot
-          else:
-            default(Eth2Digest)
-
-      await self.runForkchoiceUpdated(headBlockRoot, finalizedBlockRoot)

beacon_chain/networking/network_metadata.nim

@@ -169,7 +169,9 @@ proc loadEth2NetworkMetadata*(path: string, eth1Network = none(Eth1Network)): Et
           let data = (genesisData[0 ..< 40].toHex())
           data in [
             # Prater
-            "60F4596000000000043DB0D9A83813551EE2F33450D23797757D430911A9320530AD8A0EABC43EFB"
+            "60F4596000000000043DB0D9A83813551EE2F33450D23797757D430911A9320530AD8A0EABC43EFB",
+            # Kiln
+            "0C572B620000000099B09FCD43E5905236C370F184056BEC6E6638CFC31A323B304FC4AA789CB4AD"
           ]
         else:
           false

beacon_chain/spec/helpers.nim

@@ -506,3 +506,30 @@ func compute_timestamp_at_slot*(state: ForkyBeaconState, slot: Slot): uint64 =
   # Note: This function is unsafe with respect to overflows and underflows.
   let slots_since_genesis = slot - GENESIS_SLOT
   state.genesis_time + slots_since_genesis * SECONDS_PER_SLOT
+
+# https://github.com/ethereum/consensus-specs/blob/v1.1.10/tests/core/pyspec/eth2spec/test/helpers/execution_payload.py#L1-L31
+func build_empty_execution_payload*(state: bellatrix.BeaconState): ExecutionPayload =
+  ## Assuming a pre-state of the same slot, build a valid ExecutionPayload
+  ## without any transactions.
+  let
+    latest = state.latest_execution_payload_header
+    timestamp = compute_timestamp_at_slot(state, state.slot)
+    randao_mix = get_randao_mix(state, get_current_epoch(state))
+
+  var payload = ExecutionPayload(
+    parent_hash: latest.block_hash,
+    state_root: latest.state_root, # no changes to the state
+    receipts_root: static(Eth2Digest.fromHex(
+      "0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421")),
+    block_number: latest.block_number + 1,
+    prev_randao: randao_mix,
+    gas_limit: latest.gas_limit, # retain same limit
+    gas_used: 0, # empty block, 0 gas
+    timestamp: timestamp,
+    base_fee_per_gas: latest.base_fee_per_gas) # retain same base_fee
+
+  payload.block_hash = withEth2Hash:
+    h.update payload.hash_tree_root().data
+    h.update cast[array[13, uint8]]("FAKE RLP HASH")
+
+  payload

beacon_chain/validators/validator_duties.nim

@@ -41,6 +41,7 @@ import
 
 from eth/async_utils import awaitWithTimeout
 from web3/engine_api import ForkchoiceUpdatedResponse
+from web3/engine_api_types import PayloadExecutionStatus
 
 # Metrics for tracking attestation and beacon block loss
 const delayBuckets = [-Inf, -4.0, -2.0, -1.0, -0.5, -0.1, -0.05,
@@ -434,7 +435,7 @@ proc forkchoice_updated(state: bellatrix.BeaconState,
           head_block_hash, finalized_block_hash, timestamp, random.data,
           fee_recipient),
         web3Timeout):
-          debug "forkchoice_updated: forkchoiceUpdated timed out"
+          info "forkchoice_updated: forkchoiceUpdated timed out"
           default(ForkchoiceUpdatedResponse)
     payloadId = forkchoiceResponse.payloadId
 
@@ -443,6 +444,65 @@ proc forkchoice_updated(state: bellatrix.BeaconState,
   else:
     none(bellatrix.PayloadID)
 
+proc get_execution_payload(
+    payload_id: Option[bellatrix.PayloadId], execution_engine: Eth1Monitor):
+    Future[bellatrix.ExecutionPayload] {.async.} =
+  return if payload_id.isNone():
+    # Pre-merge, empty payload
+    default(bellatrix.ExecutionPayload)
+  else:
+    asConsensusExecutionPayload(
+      await execution_engine.getPayload(payload_id.get))
+
+proc getExecutionPayload(node: BeaconNode, proposalState: auto):
+    Future[ExecutionPayload] {.async.} =
+  # https://github.com/ethereum/consensus-specs/blob/v1.1.10/specs/bellatrix/validator.md#executionpayload
+
+  # Only current hardfork with execution payloads is Bellatrix
+  static: doAssert high(BeaconStateFork) == BeaconStateFork.Bellatrix
+  template empty_execution_payload(): auto =
+    build_empty_execution_payload(proposalState.bellatrixData.data)
+
+  if node.eth1Monitor.isNil:
+    warn "getExecutionPayload: eth1Monitor not initialized; using empty execution payload"
+    return empty_execution_payload
+
+  try:
+    # Minimize window for Eth1 monitor to shut down connection
+    await node.consensusManager.eth1Monitor.ensureDataProvider()
+
+    let
+      feeRecipient =
+        if node.config.suggestedFeeRecipient.isSome:
+          node.config.suggestedFeeRecipient.get
+        else:
+          default(Eth1Address)
+      latestHead =
+        if not node.dag.head.executionBlockRoot.isZero:
+          node.dag.head.executionBlockRoot
+        else:
+          default(Eth2Digest)
+      latestFinalized = node.dag.finalizedHead.blck.executionBlockRoot
+      payload_id = (await forkchoice_updated(
+        proposalState.bellatrixData.data, latestHead, latestFinalized,
+        feeRecipient, node.consensusManager.eth1Monitor))
+      payload = await get_execution_payload(
+        payload_id, node.consensusManager.eth1Monitor)
+      executionPayloadStatus =
+        await node.consensusManager.eth1Monitor.newExecutionPayload(
+          payload)
+
+    if executionPayloadStatus != PayloadExecutionStatus.valid:
+      info "getExecutionPayload: newExecutionPayload not valid; using empty execution payload",
+        executionPayloadStatus
+      return empty_execution_payload
+
+    return payload
+  except CatchableError as err:
+    error "Error creating non-empty execution payload; using empty execution payload",
+      msg = err.msg
+    return empty_execution_payload
+
 proc makeBeaconBlockForHeadAndSlot*(node: BeaconNode,
                                     randao_reveal: ValidatorSig,
                                     validator_index: ValidatorIndex,
@@ -472,6 +532,9 @@ proc makeBeaconBlockForHeadAndSlot*(node: BeaconNode,
       warn "Eth1 deposits not available. Skipping block proposal", slot
       return ForkedBlockResult.err("Eth1 deposits not available")
 
+    # Only current hardfork with execution payloads is Bellatrix
+    static: doAssert high(BeaconStateFork) == BeaconStateFork.Bellatrix
+
     let exits = withState(state):
       node.exitPool[].getBeaconBlockExits(state.data)
     let res = makeBeaconBlock(
@@ -488,7 +551,13 @@ proc makeBeaconBlockForHeadAndSlot*(node: BeaconNode,
         SyncAggregate.init()
       else:
         node.syncCommitteeMsgPool[].produceSyncAggregate(head.root),
-      default(bellatrix.ExecutionPayload),
+      if  slot.epoch < node.dag.cfg.BELLATRIX_FORK_EPOCH or
+          # TODO when Eth1Monitor TTD following comes in, actually detect
+          # transition block directly
+          not is_merge_transition_complete(proposalState.bellatrixData.data):
+        default(bellatrix.ExecutionPayload)
+      else:
+        (await getExecutionPayload(node, proposalState)),
       noRollback, # Temporary state - no need for rollback
       cache)
     if res.isErr():

tests/mocking/mock_blocks.nim

@@ -43,33 +43,6 @@ func sign_block(state: ForkyBeaconState, blck: var ForkySignedBeaconBlock) =
     blck.root,
     privkey).toValidatorSig()
 
-# https://github.com/ethereum/consensus-specs/blob/v1.1.10/tests/core/pyspec/eth2spec/test/helpers/execution_payload.py#L1-L31
-func build_empty_execution_payload(state: bellatrix.BeaconState): ExecutionPayload =
-  ## Assuming a pre-state of the same slot, build a valid ExecutionPayload
-  ## without any transactions.
-  let
-    latest = state.latest_execution_payload_header
-    timestamp = compute_timestamp_at_slot(state, state.slot)
-    randao_mix = get_randao_mix(state, get_current_epoch(state))
-
-  var payload = ExecutionPayload(
-    parent_hash: latest.block_hash,
-    state_root: latest.state_root, # no changes to the state
-    receipts_root: Eth2Digest(data: cast[array[32, uint8]](
-      "no receipts here\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0")),
-    block_number: latest.block_number + 1,
-    prev_randao: randao_mix,
-    gas_limit: latest.gas_limit, # retain same limit
-    gas_used: 0, # empty block, 0 gas
-    timestamp: timestamp,
-    base_fee_per_gas: latest.base_fee_per_gas) # retain same base_fee
-
-  payload.block_hash = withEth2Hash:
-    h.update payload.hash_tree_root().data
-    h.update cast[array[13, uint8]]("FAKE RLP HASH")
-
-  payload
-
 # https://github.com/ethereum/consensus-specs/blob/v1.1.10/tests/core/pyspec/eth2spec/test/helpers/block.py#L75-L104
 proc mockBlock*(
     state: ForkedHashedBeaconState,