Allow producing block with execution payload

beacon_node/beacon_chain/src/beacon_chain.rs

@@ -60,7 +60,9 @@ use slot_clock::SlotClock;
 use state_processing::{
     common::get_indexed_attestation,
     per_block_processing,
-    per_block_processing::errors::AttestationValidationError,
+    per_block_processing::{
+        compute_timestamp_at_slot, errors::AttestationValidationError, is_merge_complete,
+    },
     per_slot_processing,
     state_advance::{complete_state_advance, partial_state_advance},
     BlockSignatureStrategy, SigVerifiedOp,
@@ -2790,12 +2792,44 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                 }))
         };
         // Closure to fetch a sync aggregate in cases where it is required.
-        let get_execution_payload = || -> Result<ExecutionPayload<_>, BlockProductionError> {
+        let get_execution_payload = |latest_execution_payload_header: &ExecutionPayloadHeader<
-            // TODO: actually get the payload from eth1 node..
+            T::EthSpec,
-            Ok(ExecutionPayload::default())
+        >|
+         -> Result<ExecutionPayload<_>, BlockProductionError> {
+            let execution_layer = self
+                .execution_layer
+                .as_ref()
+                .ok_or(BlockProductionError::ExecutionLayerMissing)?;
+
+            let parent_hash;
+            if !is_merge_complete(&state) {
+                let terminal_pow_block_hash = execution_layer
+                    .block_on(|execution_layer| {
+                        execution_layer.get_pow_block_hash_at_total_difficulty()
+                    })
+                    .map_err(BlockProductionError::TerminalPoWBlockLookupFailed)?;
+
+                if let Some(terminal_pow_block_hash) = terminal_pow_block_hash {
+                    parent_hash = terminal_pow_block_hash;
+                } else {
+                    return Ok(<_>::default());
+                }
+            } else {
+                parent_hash = latest_execution_payload_header.block_hash;
+            }
+
+            let timestamp =
+                compute_timestamp_at_slot(&state, &self.spec).map_err(BeaconStateError::from)?;
+            let random = *state.get_randao_mix(state.current_epoch())?;
+
+            execution_layer
+                .block_on(|execution_layer| {
+                    execution_layer.get_payload(parent_hash, timestamp, random)
+                })
+                .map_err(BlockProductionError::GetPayloadFailed)
         };
 
-        let inner_block = match state {
+        let inner_block = match &state {
             BeaconState::Base(_) => BeaconBlock::Base(BeaconBlockBase {
                 slot,
                 proposer_index,
@@ -2832,9 +2866,10 @@ impl<T: BeaconChainTypes> BeaconChain<T> {
                     },
                 })
             }
-            BeaconState::Merge(_) => {
+            BeaconState::Merge(state) => {
                 let sync_aggregate = get_sync_aggregate()?;
-                let execution_payload = get_execution_payload()?;
+                let execution_payload =
+                    get_execution_payload(&state.latest_execution_payload_header)?;
                 BeaconBlock::Merge(BeaconBlockMerge {
                     slot,
                     proposer_index,

beacon_node/beacon_chain/src/errors.rs

@@ -177,6 +177,9 @@ pub enum BlockProductionError {
         produce_at_slot: Slot,
         state_slot: Slot,
     },
+    ExecutionLayerMissing,
+    TerminalPoWBlockLookupFailed(execution_layer::Error),
+    GetPayloadFailed(execution_layer::Error),
 }
 
 easy_from_to!(BlockProcessingError, BlockProductionError);

beacon_node/client/src/builder.rs

@@ -156,6 +156,7 @@ where
             let execution_layer = ExecutionLayer::from_urls(
                 execution_endpoints,
                 terminal_total_difficulty,
+                config.fee_recipient,
                 context.executor.clone(),
                 context.log().clone(),
             )

beacon_node/client/src/config.rs

@@ -4,7 +4,7 @@ use sensitive_url::SensitiveUrl;
 use serde_derive::{Deserialize, Serialize};
 use std::fs;
 use std::path::PathBuf;
-use types::{Graffiti, PublicKeyBytes, Uint256};
+use types::{Address, Graffiti, PublicKeyBytes, Uint256};
 
 /// Default directory name for the freezer database under the top-level data dir.
 const DEFAULT_FREEZER_DB_DIR: &str = "freezer_db";
@@ -76,6 +76,7 @@ pub struct Config {
     pub eth1: eth1::Config,
     pub execution_endpoints: Option<Vec<SensitiveUrl>>,
     pub terminal_total_difficulty_override: Option<Uint256>,
+    pub fee_recipient: Option<Address>,
     pub http_api: http_api::Config,
     pub http_metrics: http_metrics::Config,
     pub monitoring_api: Option<monitoring_api::Config>,
@@ -98,6 +99,7 @@ impl Default for Config {
             eth1: <_>::default(),
             execution_endpoints: None,
             terminal_total_difficulty_override: None,
+            fee_recipient: None,
             disabled_forks: Vec::new(),
             graffiti: Graffiti::default(),
             http_api: <_>::default(),

beacon_node/execution_layer/src/lib.rs

@@ -20,6 +20,7 @@ pub enum Error {
     EngineErrors(Vec<EngineError>),
     NotSynced,
     ShuttingDown,
+    FeeRecipientUnspecified,
 }
 
 impl From<ApiError> for Error {
@@ -31,6 +32,7 @@ impl From<ApiError> for Error {
 struct Inner {
     engines: Engines<HttpJsonRpc>,
     terminal_total_difficulty: Uint256,
+    fee_recipient: Option<Address>,
     executor: TaskExecutor,
     log: Logger,
 }
@@ -44,6 +46,7 @@ impl ExecutionLayer {
     pub fn from_urls(
         urls: Vec<SensitiveUrl>,
         terminal_total_difficulty: Uint256,
+        fee_recipient: Option<Address>,
         executor: TaskExecutor,
         log: Logger,
     ) -> Result<Self, Error> {
@@ -62,6 +65,7 @@ impl ExecutionLayer {
                 log: log.clone(),
             },
             terminal_total_difficulty,
+            fee_recipient,
             executor,
             log,
         };
@@ -85,6 +89,12 @@ impl ExecutionLayer {
         self.inner.terminal_total_difficulty
     }
 
+    fn fee_recipient(&self) -> Result<Address, Error> {
+        self.inner
+            .fee_recipient
+            .ok_or(Error::FeeRecipientUnspecified)
+    }
+
     fn log(&self) -> &Logger {
         &self.inner.log
     }
@@ -118,10 +128,11 @@ impl ExecutionLayer {
         parent_hash: Hash256,
         timestamp: u64,
         random: Hash256,
-        fee_recipient: Address,
     ) -> Result<PayloadId, Error> {
+        let fee_recipient = self.fee_recipient()?;
         self.engines()
             .first_success(|engine| {
+                // TODO(paul): put these in a cache.
                 engine
                     .api
                     .prepare_payload(parent_hash, timestamp, random, fee_recipient)
@@ -130,6 +141,27 @@ impl ExecutionLayer {
             .map_err(Error::EngineErrors)
     }
 
+    pub async fn get_payload<T: EthSpec>(
+        &self,
+        parent_hash: Hash256,
+        timestamp: u64,
+        random: Hash256,
+    ) -> Result<ExecutionPayload<T>, Error> {
+        let fee_recipient = self.fee_recipient()?;
+        self.engines()
+            .first_success(|engine| async move {
+                // TODO(paul): make a cache for these IDs.
+                let payload_id = engine
+                    .api
+                    .prepare_payload(parent_hash, timestamp, random, fee_recipient)
+                    .await?;
+
+                engine.api.get_payload(payload_id).await
+            })
+            .await
+            .map_err(Error::EngineErrors)
+    }
+
     pub async fn execute_payload<T: EthSpec>(
         &self,
         execution_payload: &ExecutionPayload<T>,
@@ -226,7 +258,7 @@ impl ExecutionLayer {
         }
     }
 
-    pub async fn get_pow_block_at_total_difficulty(&self) -> Result<Option<Hash256>, Error> {
+    pub async fn get_pow_block_hash_at_total_difficulty(&self) -> Result<Option<Hash256>, Error> {
         self.engines()
             .first_success(|engine| async move {
                 let mut ttd_exceeding_block = None;
@@ -239,6 +271,7 @@ impl ExecutionLayer {
                     if block.total_difficulty >= self.terminal_total_difficulty() {
                         ttd_exceeding_block = Some(block.block_hash);
 
+                        // TODO(paul): add a LRU cache for these lookups.
                         block = engine.api.get_block_by_hash(block.parent_hash).await?;
                     } else {
                         return Ok::<_, ApiError>(ttd_exceeding_block);

beacon_node/src/cli.rs

@@ -380,6 +380,17 @@ pub fn cli_app<'a, 'b>() -> App<'a, 'b> {
                        Be extremely careful with the use of this flag.")
                 .takes_value(true)
         )
+        .arg(
+            Arg::with_name("fee-recipient")
+                .long("fee-recipient")
+                .help("Once the merge has happened, this address will receive transaction fees \
+                       collected from any blocks produced by this node. Defaults to a junk \
+                       address whilst the merge is in development stages. THE DEFAULT VALUE \
+                       WILL BE REMOVED BEFORE THE MERGE ENTERS PRODUCTION")
+                // TODO: remove this default value. It's just there to make life easy during merge
+                // testnets.
+                .default_value("0x000000000000000000000000000000000000000000000001"),
+        )
 
         /*
          * Database purging and compaction.

beacon_node/src/config.rs

@@ -237,6 +237,8 @@ pub fn get_config<E: EthSpec>(
         client_config.terminal_total_difficulty_override = Some(terminal_total_difficulty);
     }
 
+    client_config.fee_recipient = clap_utils::parse_optional(cli_args, "fee-recipient")?;
+
     if let Some(freezer_dir) = cli_args.value_of("freezer-dir") {
         client_config.freezer_db_path = Some(PathBuf::from(freezer_dir));
     }