Refactor beacon_chain.

Moves all the `BeaconChain` impls into the same file that the struct is
defined in.

beacon_node/beacon_chain/src/lib.rs

@@ -1,129 +1,9 @@
 mod attestation_aggregator;
-pub mod attestation_processing;
-mod attestation_production;
 mod attestation_targets;
+mod beacon_chain;
 mod block_graph;
-pub mod block_processing;
-pub mod block_production;
-mod canonical_head;
 mod checkpoint;
-pub mod dump;
-mod finalized_head;
-mod getters;
 mod lmd_ghost;
-mod state;
 
-use self::attestation_targets::AttestationTargets;
-use self::block_graph::BlockGraph;
-use attestation_aggregator::AttestationAggregator;
-use db::{
-    stores::{BeaconBlockStore, BeaconStateStore},
-    ClientDB, DBError,
-};
-use genesis::{genesis_beacon_block, genesis_beacon_state, GenesisError};
-use parking_lot::RwLock;
-use slot_clock::SlotClock;
-use ssz::ssz_encode;
-use std::sync::Arc;
-use types::{BeaconState, ChainSpec, Hash256};
-
-pub use self::block_processing::Outcome as BlockProcessingOutcome;
+pub use self::beacon_chain::{BeaconChain, Error};
 pub use self::checkpoint::CheckPoint;
-
-#[derive(Debug, PartialEq)]
-pub enum BeaconChainError {
-    InsufficientValidators,
-    GenesisError(GenesisError),
-    DBError(String),
-}
-
-pub struct BeaconChain<T: ClientDB + Sized, U: SlotClock> {
-    pub block_store: Arc<BeaconBlockStore<T>>,
-    pub state_store: Arc<BeaconStateStore<T>>,
-    pub slot_clock: U,
-    pub block_graph: BlockGraph,
-    pub attestation_aggregator: RwLock<AttestationAggregator>,
-    canonical_head: RwLock<CheckPoint>,
-    finalized_head: RwLock<CheckPoint>,
-    justified_head: RwLock<CheckPoint>,
-    pub state: RwLock<BeaconState>,
-    pub latest_attestation_targets: RwLock<AttestationTargets>,
-    pub spec: ChainSpec,
-}
-
-impl<T, U> BeaconChain<T, U>
-where
-    T: ClientDB,
-    U: SlotClock,
-{
-    /// Instantiate a new Beacon Chain, from genesis.
-    pub fn genesis(
-        state_store: Arc<BeaconStateStore<T>>,
-        block_store: Arc<BeaconBlockStore<T>>,
-        slot_clock: U,
-        spec: ChainSpec,
-    ) -> Result<Self, BeaconChainError> {
-        if spec.initial_validators.is_empty() {
-            return Err(BeaconChainError::InsufficientValidators);
-        }
-
-        let genesis_state = genesis_beacon_state(&spec)?;
-        let state_root = genesis_state.canonical_root();
-        state_store.put(&state_root, &ssz_encode(&genesis_state)[..])?;
-
-        let genesis_block = genesis_beacon_block(state_root, &spec);
-        let block_root = genesis_block.canonical_root();
-        block_store.put(&block_root, &ssz_encode(&genesis_block)[..])?;
-
-        let block_graph = BlockGraph::new();
-        block_graph.add_leaf(&Hash256::zero(), block_root.clone());
-
-        let finalized_head = RwLock::new(CheckPoint::new(
-            genesis_block.clone(),
-            block_root.clone(),
-            genesis_state.clone(),
-            state_root.clone(),
-        ));
-        let justified_head = RwLock::new(CheckPoint::new(
-            genesis_block.clone(),
-            block_root.clone(),
-            genesis_state.clone(),
-            state_root.clone(),
-        ));
-        let canonical_head = RwLock::new(CheckPoint::new(
-            genesis_block.clone(),
-            block_root.clone(),
-            genesis_state.clone(),
-            state_root.clone(),
-        ));
-        let attestation_aggregator = RwLock::new(AttestationAggregator::new());
-
-        let latest_attestation_targets = RwLock::new(AttestationTargets::new());
-
-        Ok(Self {
-            block_store,
-            state_store,
-            slot_clock,
-            block_graph,
-            attestation_aggregator,
-            state: RwLock::new(genesis_state.clone()),
-            justified_head,
-            finalized_head,
-            canonical_head,
-            latest_attestation_targets,
-            spec: spec,
-        })
-    }
-}
-
-impl From<DBError> for BeaconChainError {
-    fn from(e: DBError) -> BeaconChainError {
-        BeaconChainError::DBError(e.message)
-    }
-}
-
-impl From<GenesisError> for BeaconChainError {
-    fn from(e: GenesisError) -> BeaconChainError {
-        BeaconChainError::GenesisError(e)
-    }
-}