lighthouse/beacon_chain/chain/src/block_context.rs
2018-10-30 15:49:32 +01:00

94 lines
3.3 KiB
Rust

use super::BeaconChain;
use db::stores::BeaconBlockAtSlotError;
use db::ClientDB;
use ssz_helpers::ssz_beacon_block::SszBeaconBlock;
use std::sync::Arc;
use types::Hash256;
use validation::block_validation::BeaconBlockValidationContext;
pub enum BlockValidationContextError {
UnknownCrystallizedState,
UnknownActiveState,
UnknownAttesterProposerMaps,
NoParentHash,
UnknownJustifiedBlock,
BlockAlreadyKnown,
BlockSlotLookupError(BeaconBlockAtSlotError),
}
impl From<BeaconBlockAtSlotError> for BlockValidationContextError {
fn from(e: BeaconBlockAtSlotError) -> BlockValidationContextError {
BlockValidationContextError::BlockSlotLookupError(e)
}
}
impl<T> BeaconChain<T>
where
T: ClientDB + Sized,
{
pub(crate) fn block_validation_context(
&self,
block: &SszBeaconBlock,
parent_block: &SszBeaconBlock,
present_slot: u64,
) -> Result<BeaconBlockValidationContext<T>, BlockValidationContextError> {
/*
* Load the crystallized state for this block from our caches.
*
* Fail if the crystallized state is unknown.
*/
let cry_state_root = Hash256::from(parent_block.cry_state_root());
let cry_state = self
.crystallized_states
.get(&cry_state_root)
.ok_or(BlockValidationContextError::UnknownCrystallizedState)?;
/*
* Load the active state for this block from our caches.
*
* Fail if the active state is unknown.
*/
let act_state_root = Hash256::from(parent_block.act_state_root());
let act_state = self
.active_states
.get(&act_state_root)
.ok_or(BlockValidationContextError::UnknownActiveState)?;
/*
* Learn the last justified slot from the crystallized state and load
* the hash of this block from the database
*/
let last_justified_slot = cry_state.last_justified_slot;
let parent_block_hash = block
.parent_hash()
.ok_or(BlockValidationContextError::NoParentHash)?;
let (last_justified_block_hash, _) = self
.store
.block
.block_at_slot(&parent_block_hash, last_justified_slot)?
.ok_or(BlockValidationContextError::UnknownJustifiedBlock)?;
/*
* Load the attester and proposer maps for the crystallized state.
*/
let (attester_map, proposer_map) = self
.attester_proposer_maps
.get(&cry_state_root)
.ok_or(BlockValidationContextError::UnknownAttesterProposerMaps)?;
Ok(BeaconBlockValidationContext {
present_slot,
cycle_length: self.config.cycle_length,
last_justified_slot: cry_state.last_justified_slot,
last_justified_block_hash: Hash256::from(&last_justified_block_hash[..]),
last_finalized_slot: self.last_finalized_slot,
recent_block_hashes: Arc::new(act_state.recent_block_hashes.clone()),
proposer_map: proposer_map.clone(),
attester_map: attester_map.clone(),
block_store: self.store.block.clone(),
validator_store: self.store.validator.clone(),
pow_store: self.store.pow_chain.clone(),
})
}
}