lighthouse/beacon_node/beacon_chain/src/beacon_chain.rs

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use crate::attestation_aggregator::{AttestationAggregator, Outcome as AggregationOutcome};
use crate::checkpoint::CheckPoint;
use crate::errors::{BeaconChainError as Error, BlockProductionError};
use db::{
stores::{BeaconBlockStore, BeaconStateStore},
ClientDB, DBError,
};
use fork_choice::{ForkChoice, ForkChoiceError};
use log::{debug, trace};
use operation_pool::DepositInsertStatus;
use operation_pool::OperationPool;
use parking_lot::{RwLock, RwLockReadGuard};
use slot_clock::SlotClock;
use ssz::ssz_encode;
pub use state_processing::per_block_processing::errors::{
AttestationValidationError, AttesterSlashingValidationError, DepositValidationError,
ExitValidationError, ProposerSlashingValidationError, TransferValidationError,
};
use state_processing::{
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per_block_processing, per_block_processing_without_verifying_block_signature,
per_slot_processing, BlockProcessingError, SlotProcessingError,
};
use std::sync::Arc;
use types::*;
#[derive(Debug, PartialEq)]
pub enum ValidBlock {
/// The block was successfully processed.
Processed,
}
#[derive(Debug, PartialEq)]
pub enum InvalidBlock {
/// The block slot is greater than the present slot.
FutureSlot {
present_slot: Slot,
block_slot: Slot,
},
/// The block state_root does not match the generated state.
StateRootMismatch,
/// The blocks parent_root is unknown.
ParentUnknown,
/// There was an error whilst advancing the parent state to the present slot. This condition
/// should not occur, it likely represents an internal error.
SlotProcessingError(SlotProcessingError),
/// The block could not be applied to the state, it is invalid.
PerBlockProcessingError(BlockProcessingError),
}
#[derive(Debug, PartialEq)]
pub enum BlockProcessingOutcome {
/// The block was successfully validated.
ValidBlock(ValidBlock),
/// The block was not successfully validated.
InvalidBlock(InvalidBlock),
}
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impl BlockProcessingOutcome {
/// Returns `true` if the block was objectively invalid and we should disregard the peer who
/// sent it.
pub fn is_invalid(&self) -> bool {
match self {
BlockProcessingOutcome::ValidBlock(_) => false,
BlockProcessingOutcome::InvalidBlock(r) => match r {
InvalidBlock::FutureSlot { .. } => true,
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InvalidBlock::StateRootMismatch => true,
InvalidBlock::ParentUnknown => false,
InvalidBlock::SlotProcessingError(_) => false,
InvalidBlock::PerBlockProcessingError(e) => match e {
BlockProcessingError::Invalid(_) => true,
BlockProcessingError::BeaconStateError(_) => false,
},
},
}
}
/// Returns `true` if the block was successfully processed and can be removed from any import
/// queues or temporary storage.
pub fn sucessfully_processed(&self) -> bool {
match self {
BlockProcessingOutcome::ValidBlock(_) => true,
_ => false,
}
}
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}
pub struct BeaconChain<T: ClientDB + Sized, U: SlotClock, F: ForkChoice> {
pub block_store: Arc<BeaconBlockStore<T>>,
pub state_store: Arc<BeaconStateStore<T>>,
pub slot_clock: U,
pub attestation_aggregator: RwLock<AttestationAggregator>,
pub op_pool: RwLock<OperationPool>,
canonical_head: RwLock<CheckPoint>,
finalized_head: RwLock<CheckPoint>,
pub state: RwLock<BeaconState>,
pub spec: ChainSpec,
pub fork_choice: RwLock<F>,
}
impl<T, U, F> BeaconChain<T, U, F>
where
T: ClientDB,
U: SlotClock,
F: ForkChoice,
{
/// Instantiate a new Beacon Chain, from genesis.
pub fn from_genesis(
state_store: Arc<BeaconStateStore<T>>,
block_store: Arc<BeaconBlockStore<T>>,
slot_clock: U,
mut genesis_state: BeaconState,
genesis_block: BeaconBlock,
spec: ChainSpec,
fork_choice: F,
) -> Result<Self, Error> {
let state_root = genesis_state.canonical_root();
state_store.put(&state_root, &ssz_encode(&genesis_state)[..])?;
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let block_root = genesis_block.block_header().canonical_root();
block_store.put(&block_root, &ssz_encode(&genesis_block)[..])?;
let finalized_head = RwLock::new(CheckPoint::new(
genesis_block.clone(),
block_root,
genesis_state.clone(),
state_root,
));
let canonical_head = RwLock::new(CheckPoint::new(
genesis_block.clone(),
block_root,
genesis_state.clone(),
state_root,
));
let attestation_aggregator = RwLock::new(AttestationAggregator::new());
genesis_state.build_epoch_cache(RelativeEpoch::Previous, &spec)?;
genesis_state.build_epoch_cache(RelativeEpoch::Current, &spec)?;
genesis_state.build_epoch_cache(RelativeEpoch::NextWithoutRegistryChange, &spec)?;
genesis_state.build_epoch_cache(RelativeEpoch::NextWithRegistryChange, &spec)?;
Ok(Self {
block_store,
state_store,
slot_clock,
attestation_aggregator,
op_pool: RwLock::new(OperationPool::new()),
state: RwLock::new(genesis_state),
finalized_head,
canonical_head,
spec,
fork_choice: RwLock::new(fork_choice),
})
}
/// Returns the beacon block body for each beacon block root in `roots`.
///
/// Fails if any root in `roots` does not have a corresponding block.
pub fn get_block_bodies(&self, roots: &[Hash256]) -> Result<Vec<BeaconBlockBody>, Error> {
let bodies: Result<Vec<BeaconBlockBody>, _> = roots
.iter()
.map(|root| match self.get_block(root)? {
Some(block) => Ok(block.body),
None => Err(Error::DBInconsistent("Missing block".into())),
})
.collect();
Ok(bodies?)
}
/// Returns the beacon block header for each beacon block root in `roots`.
///
/// Fails if any root in `roots` does not have a corresponding block.
pub fn get_block_headers(&self, roots: &[Hash256]) -> Result<Vec<BeaconBlockHeader>, Error> {
let headers: Result<Vec<BeaconBlockHeader>, _> = roots
.iter()
.map(|root| match self.get_block(root)? {
Some(block) => Ok(block.block_header()),
None => Err(Error::DBInconsistent("Missing block".into())),
})
.collect();
Ok(headers?)
}
/// Returns `count `beacon block roots, starting from `start_slot` with an
/// interval of `skip` slots between each root.
///
/// ## Errors:
///
/// - `SlotOutOfBounds`: Unable to return the full specified range.
/// - `SlotOutOfBounds`: Unable to load a state from the DB.
/// - `SlotOutOfBounds`: Start slot is higher than the first slot.
/// - Other: BeaconState` is inconsistent.
pub fn get_block_roots(
&self,
earliest_slot: Slot,
count: usize,
skip: usize,
) -> Result<Vec<Hash256>, Error> {
let spec = &self.spec;
let step_by = Slot::from(skip + 1);
let mut roots: Vec<Hash256> = vec![];
// The state for reading block roots. Will be updated with an older state if slots go too
// far back in history.
let mut state = self.state.read().clone();
// The final slot in this series, will be reduced by `skip` each loop iteration.
let mut slot = earliest_slot + Slot::from(count * (skip + 1)) - 1;
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// If the highest slot requested is that of the current state insert the root of the
// head block, unless the head block's slot is not matching.
if slot == state.slot && self.head().beacon_block.slot == slot {
roots.push(self.head().beacon_block_root);
slot -= step_by;
} else if slot >= state.slot {
return Err(BeaconStateError::SlotOutOfBounds.into());
}
loop {
// If the slot is within the range of the current state's block roots, append the root
// to the output vec.
//
// If we get `SlotOutOfBounds` error, load the oldest available historic
// state from the DB.
match state.get_block_root(slot, spec) {
Ok(root) => {
if slot < earliest_slot {
break;
} else {
roots.push(*root);
slot -= step_by;
}
}
Err(BeaconStateError::SlotOutOfBounds) => {
// Read the earliest historic state in the current slot.
let earliest_historic_slot =
state.slot - Slot::from(spec.slots_per_historical_root);
// Load the earlier state from disk.
let new_state_root = state.get_state_root(earliest_historic_slot, spec)?;
// Break if the DB is unable to load the state.
state = match self.state_store.get_deserialized(&new_state_root) {
Ok(Some(state)) => state,
_ => break,
}
}
Err(e) => return Err(e.into()),
};
}
// Return the results if they pass a sanity check.
if (slot <= earliest_slot) && (roots.len() == count) {
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// Reverse the ordering of the roots. We extracted them in reverse order to make it
// simpler to lookup historic states.
//
// This is a potential optimisation target.
Ok(roots.iter().rev().cloned().collect())
} else {
Err(BeaconStateError::SlotOutOfBounds.into())
}
}
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/// Returns the block at the given root, if any.
///
/// ## Errors
///
/// May return a database error.
pub fn get_block(&self, block_root: &Hash256) -> Result<Option<BeaconBlock>, Error> {
Ok(self.block_store.get_deserialized(block_root)?)
}
/// Update the canonical head to some new values.
pub fn update_canonical_head(
&self,
new_beacon_block: BeaconBlock,
new_beacon_block_root: Hash256,
new_beacon_state: BeaconState,
new_beacon_state_root: Hash256,
) {
debug!(
"Updating canonical head with block at slot: {}",
new_beacon_block.slot
);
let mut head = self.canonical_head.write();
head.update(
new_beacon_block,
new_beacon_block_root,
new_beacon_state,
new_beacon_state_root,
);
}
/// Returns a read-lock guarded `CheckPoint` struct for reading the head (as chosen by the
/// fork-choice rule).
///
/// It is important to note that the `beacon_state` returned may not match the present slot. It
/// is the state as it was when the head block was recieved, which could be some slots prior to
/// now.
pub fn head(&self) -> RwLockReadGuard<CheckPoint> {
self.canonical_head.read()
}
/// Updates the canonical `BeaconState` with the supplied state.
///
/// Advances the chain forward to the present slot. This method is better than just setting
/// state and calling `catchup_state` as it will not result in an old state being installed and
/// then having it iteratively updated -- in such a case it's possible for another thread to
/// find the state at an old slot.
pub fn update_state(&self, mut state: BeaconState) -> Result<(), Error> {
let latest_block_header = self.head().beacon_block.block_header();
let present_slot = match self.slot_clock.present_slot() {
Ok(Some(slot)) => slot,
_ => return Err(Error::UnableToReadSlot),
};
// If required, transition the new state to the present slot.
for _ in state.slot.as_u64()..present_slot.as_u64() {
per_slot_processing(&mut state, &latest_block_header, &self.spec)?;
}
*self.state.write() = state;
Ok(())
}
/// Ensures the current canonical `BeaconState` has been transitioned to match the `slot_clock`.
pub fn catchup_state(&self) -> Result<(), Error> {
let latest_block_header = self.head().beacon_block.block_header();
let present_slot = match self.slot_clock.present_slot() {
Ok(Some(slot)) => slot,
_ => return Err(Error::UnableToReadSlot),
};
let mut state = self.state.write();
// If required, transition the new state to the present slot.
for _ in state.slot.as_u64()..present_slot.as_u64() {
// Ensure the next epoch state caches are built in case of an epoch transition.
state.build_epoch_cache(RelativeEpoch::NextWithoutRegistryChange, &self.spec)?;
state.build_epoch_cache(RelativeEpoch::NextWithRegistryChange, &self.spec)?;
per_slot_processing(&mut *state, &latest_block_header, &self.spec)?;
}
state.build_epoch_cache(RelativeEpoch::Previous, &self.spec)?;
state.build_epoch_cache(RelativeEpoch::Current, &self.spec)?;
state.build_epoch_cache(RelativeEpoch::NextWithoutRegistryChange, &self.spec)?;
state.build_epoch_cache(RelativeEpoch::NextWithRegistryChange, &self.spec)?;
state.update_pubkey_cache()?;
Ok(())
}
/// Update the justified head to some new values.
pub fn update_finalized_head(
&self,
new_beacon_block: BeaconBlock,
new_beacon_block_root: Hash256,
new_beacon_state: BeaconState,
new_beacon_state_root: Hash256,
) {
let mut finalized_head = self.finalized_head.write();
finalized_head.update(
new_beacon_block,
new_beacon_block_root,
new_beacon_state,
new_beacon_state_root,
);
}
/// Returns a read-lock guarded `CheckPoint` struct for reading the justified head (as chosen,
/// indirectly, by the fork-choice rule).
pub fn finalized_head(&self) -> RwLockReadGuard<CheckPoint> {
self.finalized_head.read()
}
/// Returns the validator index (if any) for the given public key.
///
/// Information is retrieved from the present `beacon_state.validator_registry`.
pub fn validator_index(&self, pubkey: &PublicKey) -> Option<usize> {
for (i, validator) in self
.head()
.beacon_state
.validator_registry
.iter()
.enumerate()
{
if validator.pubkey == *pubkey {
return Some(i);
}
}
None
}
/// Reads the slot clock, returns `None` if the slot is unavailable.
///
/// The slot might be unavailable due to an error with the system clock, or if the present time
/// is before genesis (i.e., a negative slot).
///
/// This is distinct to `present_slot`, which simply reads the latest state. If a
/// call to `read_slot_clock` results in a higher slot than a call to `present_slot`,
/// `self.state` should undergo per slot processing.
pub fn read_slot_clock(&self) -> Option<Slot> {
match self.slot_clock.present_slot() {
Ok(Some(some_slot)) => Some(some_slot),
Ok(None) => None,
_ => None,
}
}
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/// Reads the slot clock (see `self.read_slot_clock()` and returns the number of slots since
/// genesis.
pub fn slots_since_genesis(&self) -> Option<SlotHeight> {
let now = self.read_slot_clock()?;
if now < self.spec.genesis_slot {
None
} else {
Some(SlotHeight::from(
now.as_u64() - self.spec.genesis_slot.as_u64(),
))
}
}
/// Returns slot of the present state.
///
/// This is distinct to `read_slot_clock`, which reads from the actual system clock. If
/// `self.state` has not been transitioned it is possible for the system clock to be on a
/// different slot to what is returned from this call.
pub fn present_slot(&self) -> Slot {
self.state.read().slot
}
/// Returns the block proposer for a given slot.
///
/// Information is read from the present `beacon_state` shuffling, so only information from the
/// present and prior epoch is available.
pub fn block_proposer(&self, slot: Slot) -> Result<usize, BeaconStateError> {
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self.state
.write()
.build_epoch_cache(RelativeEpoch::Current, &self.spec)?;
let index = self.state.read().get_beacon_proposer_index(
slot,
RelativeEpoch::Current,
&self.spec,
)?;
Ok(index)
}
/// Returns the attestation slot and shard for a given validator index.
///
/// Information is read from the current state, so only information from the present and prior
/// epoch is available.
pub fn validator_attestion_slot_and_shard(
&self,
validator_index: usize,
) -> Result<Option<(Slot, u64)>, BeaconStateError> {
trace!(
"BeaconChain::validator_attestion_slot_and_shard: validator_index: {}",
validator_index
);
if let Some(attestation_duty) = self
.state
.read()
.get_attestation_duties(validator_index, &self.spec)?
{
Ok(Some((attestation_duty.slot, attestation_duty.shard)))
} else {
Ok(None)
}
}
/// Produce an `AttestationData` that is valid for the present `slot` and given `shard`.
pub fn produce_attestation(&self, shard: u64) -> Result<AttestationData, Error> {
trace!("BeaconChain::produce_attestation: shard: {}", shard);
let source_epoch = self.state.read().current_justified_epoch;
let source_root = *self.state.read().get_block_root(
source_epoch.start_slot(self.spec.slots_per_epoch),
&self.spec,
)?;
let target_root = *self.state.read().get_block_root(
self.state
.read()
.slot
.epoch(self.spec.slots_per_epoch)
.start_slot(self.spec.slots_per_epoch),
&self.spec,
)?;
Ok(AttestationData {
slot: self.state.read().slot,
shard,
beacon_block_root: self.head().beacon_block_root,
target_root,
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crosslink_data_root: Hash256::zero(),
previous_crosslink: Crosslink {
epoch: self.state.read().slot.epoch(self.spec.slots_per_epoch),
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crosslink_data_root: Hash256::zero(),
},
source_epoch,
source_root,
})
}
/// Validate a `FreeAttestation` and either:
///
/// - Create a new `Attestation`.
/// - Aggregate it to an existing `Attestation`.
pub fn process_free_attestation(
&self,
free_attestation: FreeAttestation,
) -> Result<AggregationOutcome, Error> {
let aggregation_outcome = self
.attestation_aggregator
.write()
.process_free_attestation(&self.state.read(), &free_attestation, &self.spec)?;
// return if the attestation is invalid
if !aggregation_outcome.valid {
return Ok(aggregation_outcome);
}
// valid attestation, proceed with fork-choice logic
self.fork_choice.write().add_attestation(
free_attestation.validator_index,
&free_attestation.data.beacon_block_root,
&self.spec,
)?;
Ok(aggregation_outcome)
}
/// Accept a new attestation from the network.
///
/// If valid, the attestation is added to the `op_pool` and aggregated with another attestation
/// if possible.
pub fn process_attestation(
&self,
attestation: Attestation,
) -> Result<(), AttestationValidationError> {
self.op_pool
.write()
.insert_attestation(attestation, &*self.state.read(), &self.spec)
}
/// Accept some deposit and queue it for inclusion in an appropriate block.
pub fn process_deposit(
&self,
deposit: Deposit,
) -> Result<DepositInsertStatus, DepositValidationError> {
self.op_pool
.write()
.insert_deposit(deposit, &*self.state.read(), &self.spec)
}
/// Accept some exit and queue it for inclusion in an appropriate block.
pub fn process_voluntary_exit(&self, exit: VoluntaryExit) -> Result<(), ExitValidationError> {
self.op_pool
.write()
.insert_voluntary_exit(exit, &*self.state.read(), &self.spec)
}
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/// Accept some transfer and queue it for inclusion in an appropriate block.
pub fn process_transfer(&self, transfer: Transfer) -> Result<(), TransferValidationError> {
self.op_pool
.write()
.insert_transfer(transfer, &*self.state.read(), &self.spec)
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}
/// Accept some proposer slashing and queue it for inclusion in an appropriate block.
pub fn process_proposer_slashing(
&self,
proposer_slashing: ProposerSlashing,
) -> Result<(), ProposerSlashingValidationError> {
self.op_pool.write().insert_proposer_slashing(
proposer_slashing,
&*self.state.read(),
&self.spec,
)
}
/// Accept some attester slashing and queue it for inclusion in an appropriate block.
pub fn process_attester_slashing(
&self,
attester_slashing: AttesterSlashing,
) -> Result<(), AttesterSlashingValidationError> {
self.op_pool.write().insert_attester_slashing(
attester_slashing,
&*self.state.read(),
&self.spec,
)
}
/// Accept some block and attempt to add it to block DAG.
///
/// Will accept blocks from prior slots, however it will reject any block from a future slot.
pub fn process_block(&self, block: BeaconBlock) -> Result<BlockProcessingOutcome, Error> {
debug!("Processing block with slot {}...", block.slot);
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let block_root = block.block_header().canonical_root();
let present_slot = self.present_slot();
if block.slot > present_slot {
return Ok(BlockProcessingOutcome::InvalidBlock(
InvalidBlock::FutureSlot {
present_slot,
block_slot: block.slot,
},
));
}
// Load the blocks parent block from the database, returning invalid if that block is not
// found.
let parent_block_root = block.previous_block_root;
let parent_block = match self.block_store.get_deserialized(&parent_block_root)? {
Some(previous_block_root) => previous_block_root,
None => {
return Ok(BlockProcessingOutcome::InvalidBlock(
InvalidBlock::ParentUnknown,
));
}
};
// Load the parent blocks state from the database, returning an error if it is not found.
// It is an error because if know the parent block we should also know the parent state.
let parent_state_root = parent_block.state_root;
let parent_state = self
.state_store
.get_deserialized(&parent_state_root)?
.ok_or_else(|| Error::DBInconsistent(format!("Missing state {}", parent_state_root)))?;
// TODO: check the block proposer signature BEFORE doing a state transition. This will
// significantly lower exposure surface to DoS attacks.
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// Transition the parent state to the block slot.
let mut state = parent_state;
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let previous_block_header = parent_block.block_header();
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for _ in state.slot.as_u64()..block.slot.as_u64() {
if let Err(e) = per_slot_processing(&mut state, &previous_block_header, &self.spec) {
return Ok(BlockProcessingOutcome::InvalidBlock(
InvalidBlock::SlotProcessingError(e),
));
}
}
// Apply the received block to its parent state (which has been transitioned into this
// slot).
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if let Err(e) = per_block_processing(&mut state, &block, &self.spec) {
return Ok(BlockProcessingOutcome::InvalidBlock(
InvalidBlock::PerBlockProcessingError(e),
));
}
let state_root = state.canonical_root();
if block.state_root != state_root {
return Ok(BlockProcessingOutcome::InvalidBlock(
InvalidBlock::StateRootMismatch,
));
}
// Store the block and state.
self.block_store.put(&block_root, &ssz_encode(&block)[..])?;
self.state_store.put(&state_root, &ssz_encode(&state)[..])?;
// run the fork_choice add_block logic
self.fork_choice
.write()
.add_block(&block, &block_root, &self.spec)?;
// If the parent block was the parent_block, automatically update the canonical head.
//
// TODO: this is a first-in-best-dressed scenario that is not ideal; fork_choice should be
// run instead.
if self.head().beacon_block_root == parent_block_root {
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self.update_canonical_head(block.clone(), block_root, state.clone(), state_root);
// Update the canonical `BeaconState`.
self.update_state(state)?;
}
Ok(BlockProcessingOutcome::ValidBlock(ValidBlock::Processed))
}
/// Produce a new block at the present slot.
///
/// The produced block will not be inherently valid, it must be signed by a block producer.
/// Block signing is out of the scope of this function and should be done by a separate program.
pub fn produce_block(
&self,
randao_reveal: Signature,
) -> Result<(BeaconBlock, BeaconState), BlockProductionError> {
debug!("Producing block at slot {}...", self.state.read().slot);
let mut state = self.state.read().clone();
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state.build_epoch_cache(RelativeEpoch::Current, &self.spec)?;
trace!("Finding attestations for new block...");
let attestations = self
.op_pool
.read()
.get_attestations(&*self.state.read(), &self.spec);
trace!(
"Inserting {} attestation(s) into new block.",
attestations.len()
);
let previous_block_root = *state
.get_block_root(state.slot - 1, &self.spec)
.map_err(|_| BlockProductionError::UnableToGetBlockRootFromState)?;
let (proposer_slashings, attester_slashings) = self
.op_pool
.read()
.get_slashings(&*self.state.read(), &self.spec);
let mut block = BeaconBlock {
slot: state.slot,
previous_block_root,
state_root: Hash256::zero(), // Updated after the state is calculated.
signature: self.spec.empty_signature.clone(), // To be completed by a validator.
body: BeaconBlockBody {
randao_reveal,
eth1_data: Eth1Data {
// TODO: replace with real data
deposit_root: Hash256::zero(),
block_hash: Hash256::zero(),
},
proposer_slashings,
attester_slashings,
attestations,
deposits: self
.op_pool
.read()
.get_deposits(&*self.state.read(), &self.spec),
voluntary_exits: self
.op_pool
.read()
.get_voluntary_exits(&*self.state.read(), &self.spec),
transfers: self
.op_pool
.read()
.get_transfers(&*self.state.read(), &self.spec),
},
};
trace!("BeaconChain::produce_block: updating state for new block.",);
per_block_processing_without_verifying_block_signature(&mut state, &block, &self.spec)?;
let state_root = state.canonical_root();
block.state_root = state_root;
Ok((block, state))
}
// TODO: Left this as is, modify later
pub fn fork_choice(&self) -> Result<(), Error> {
let present_head = self.finalized_head().beacon_block_root;
let new_head = self
.fork_choice
.write()
.find_head(&present_head, &self.spec)?;
if new_head != present_head {
let block = self
.block_store
.get_deserialized(&new_head)?
.ok_or_else(|| Error::MissingBeaconBlock(new_head))?;
let block_root = block.canonical_root();
let state = self
.state_store
.get_deserialized(&block.state_root)?
.ok_or_else(|| Error::MissingBeaconState(block.state_root))?;
let state_root = state.canonical_root();
self.update_canonical_head(block, block_root, state.clone(), state_root);
// Update the canonical `BeaconState`.
self.update_state(state)?;
}
Ok(())
}
/// Returns `true` if the given block root has not been processed.
pub fn is_new_block_root(&self, beacon_block_root: &Hash256) -> Result<bool, Error> {
Ok(!self.block_store.exists(beacon_block_root)?)
}
/// Dumps the entire canonical chain, from the head to genesis to a vector for analysis.
///
/// This could be a very expensive operation and should only be done in testing/analysis
/// activities.
pub fn chain_dump(&self) -> Result<Vec<CheckPoint>, Error> {
let mut dump = vec![];
let mut last_slot = CheckPoint {
beacon_block: self.head().beacon_block.clone(),
beacon_block_root: self.head().beacon_block_root,
beacon_state: self.head().beacon_state.clone(),
beacon_state_root: self.head().beacon_state_root,
};
dump.push(last_slot.clone());
loop {
let beacon_block_root = last_slot.beacon_block.previous_block_root;
if beacon_block_root == self.spec.zero_hash {
break; // Genesis has been reached.
}
let beacon_block = self
.block_store
.get_deserialized(&beacon_block_root)?
.ok_or_else(|| {
Error::DBInconsistent(format!("Missing block {}", beacon_block_root))
})?;
let beacon_state_root = beacon_block.state_root;
let beacon_state = self
.state_store
.get_deserialized(&beacon_state_root)?
.ok_or_else(|| {
Error::DBInconsistent(format!("Missing state {}", beacon_state_root))
})?;
let slot = CheckPoint {
beacon_block,
beacon_block_root,
beacon_state,
beacon_state_root,
};
dump.push(slot.clone());
last_slot = slot;
}
dump.reverse();
Ok(dump)
}
}
impl From<DBError> for Error {
fn from(e: DBError) -> Error {
Error::DBError(e.message)
}
}
impl From<ForkChoiceError> for Error {
fn from(e: ForkChoiceError) -> Error {
Error::ForkChoiceError(e)
}
}
impl From<BeaconStateError> for Error {
fn from(e: BeaconStateError) -> Error {
Error::BeaconStateError(e)
}
}