Remove block_graph from beacon_chain.

beacon_node/beacon_chain/src/beacon_chain.rs

@@ -17,7 +17,6 @@ use types::{
 };
 
 use crate::attestation_aggregator::{AttestationAggregator, Outcome as AggregationOutcome};
-use crate::block_graph::BlockGraph;
 use crate::checkpoint::CheckPoint;
 
 #[derive(Debug, PartialEq)]
@@ -65,7 +64,6 @@ 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 block_graph: BlockGraph,
     pub attestation_aggregator: RwLock<AttestationAggregator>,
     canonical_head: RwLock<CheckPoint>,
     finalized_head: RwLock<CheckPoint>,
@@ -101,9 +99,6 @@ where
         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);
-
         let finalized_head = RwLock::new(CheckPoint::new(
             genesis_block.clone(),
             block_root,
@@ -128,7 +123,6 @@ where
             block_store,
             state_store,
             slot_clock,
-            block_graph,
             attestation_aggregator,
             state: RwLock::new(genesis_state.clone()),
             justified_head,
@@ -484,9 +478,6 @@ where
         self.block_store.put(&block_root, &ssz_encode(&block)[..])?;
         self.state_store.put(&state_root, &ssz_encode(&state)[..])?;
 
-        // Update the block DAG.
-        self.block_graph.add_leaf(&parent_block_root, block_root);
-
         // run the fork_choice add_block logic
         self.fork_choice.add_block(&block, &block_root)?;
 

beacon_node/beacon_chain/src/block_graph.rs

@@ -1,44 +0,0 @@
-use parking_lot::{RwLock, RwLockReadGuard};
-use std::collections::HashSet;
-use types::Hash256;
-
-/// Maintains a view of the block DAG, also known as the "blockchain" (except, it tracks multiple
-/// chains eminating from a single root instead of just the head of some canonical chain).
-///
-/// The BlockGraph does not store the blocks, instead it tracks the block hashes of blocks at the
-/// tip of the DAG. It is out of the scope of the object to retrieve blocks.
-///
-/// Presently, the DAG root (genesis block) is not tracked.
-///
-/// The BlogGraph is thread-safe due to internal RwLocks.
-pub struct BlockGraph {
-    pub leaves: RwLock<HashSet<Hash256>>,
-}
-
-impl BlockGraph {
-    /// Create a new block graph without any leaves.
-    pub fn new() -> Self {
-        Self {
-            leaves: RwLock::new(HashSet::new()),
-        }
-    }
-    /// Add a new leaf to the block hash graph. Returns `true` if the leaf was built upon another
-    /// leaf.
-    pub fn add_leaf(&self, parent: &Hash256, leaf: Hash256) -> bool {
-        let mut leaves = self.leaves.write();
-
-        if leaves.contains(parent) {
-            leaves.remove(parent);
-            leaves.insert(leaf);
-            true
-        } else {
-            leaves.insert(leaf);
-            false
-        }
-    }
-
-    /// Returns a read-guarded HashSet of all leaf blocks.
-    pub fn leaves(&self) -> RwLockReadGuard<HashSet<Hash256>> {
-        self.leaves.read()
-    }
-}