Delete OnDiskConsensusContext (#8824)

Remove the `OnDiskConsensusContext` type which is no longer used at all after the merge of:

- https://github.com/sigp/lighthouse/pull/8724

This type was not necessary since the merge of Lion's change which removed the on-disk storage:

- https://github.com/sigp/lighthouse/pull/5891


Co-Authored-By: Michael Sproul <michael@sigmaprime.io>

beacon_node/store/src/consensus_context.rs

@@ -1,65 +0,0 @@
-use ssz_derive::{Decode, Encode};
-use state_processing::ConsensusContext;
-use std::collections::HashMap;
-use types::{EthSpec, Hash256, IndexedAttestation, Slot};
-
-/// The consensus context is stored on disk as part of the data availability overflow cache.
-///
-/// We use this separate struct to keep the on-disk format stable in the presence of changes to the
-/// in-memory `ConsensusContext`. You MUST NOT change the fields of this struct without
-/// superstructing it and implementing a schema migration.
-#[derive(Debug, PartialEq, Clone, Encode, Decode)]
-pub struct OnDiskConsensusContext<E: EthSpec> {
-    /// Slot to act as an identifier/safeguard
-    slot: Slot,
-    /// Proposer index of the block at `slot`.
-    proposer_index: Option<u64>,
-    /// Block root of the block at `slot`.
-    current_block_root: Option<Hash256>,
-    /// We keep the indexed attestations in the *in-memory* version of this struct so that we don't
-    /// need to regenerate them if roundtripping via this type *without* going to disk.
-    ///
-    /// They are not part of the on-disk format.
-    #[ssz(skip_serializing, skip_deserializing)]
-    indexed_attestations: HashMap<Hash256, IndexedAttestation<E>>,
-}
-
-impl<E: EthSpec> OnDiskConsensusContext<E> {
-    pub fn from_consensus_context(ctxt: ConsensusContext<E>) -> Self {
-        // Match exhaustively on fields here so we are forced to *consider* updating the on-disk
-        // format when the `ConsensusContext` fields change.
-        let ConsensusContext {
-            slot,
-            previous_epoch: _,
-            current_epoch: _,
-            proposer_index,
-            current_block_root,
-            indexed_attestations,
-        } = ctxt;
-        OnDiskConsensusContext {
-            slot,
-            proposer_index,
-            current_block_root,
-            indexed_attestations,
-        }
-    }
-
-    pub fn into_consensus_context(self) -> ConsensusContext<E> {
-        let OnDiskConsensusContext {
-            slot,
-            proposer_index,
-            current_block_root,
-            indexed_attestations,
-        } = self;
-
-        let mut ctxt = ConsensusContext::new(slot);
-
-        if let Some(proposer_index) = proposer_index {
-            ctxt = ctxt.set_proposer_index(proposer_index);
-        }
-        if let Some(block_root) = current_block_root {
-            ctxt = ctxt.set_current_block_root(block_root);
-        }
-        ctxt.set_indexed_attestations(indexed_attestations)
-    }
-}

beacon_node/store/src/lib.rs

@@ -9,7 +9,6 @@
 //! tests for implementation examples.
 pub mod blob_sidecar_list_from_root;
 pub mod config;
-pub mod consensus_context;
 pub mod errors;
 mod forwards_iter;
 pub mod hdiff;
@@ -27,7 +26,6 @@ pub mod iter;
 
 pub use self::blob_sidecar_list_from_root::BlobSidecarListFromRoot;
 pub use self::config::StoreConfig;
-pub use self::consensus_context::OnDiskConsensusContext;
 pub use self::hot_cold_store::{HotColdDB, HotStateSummary, Split};
 pub use self::memory_store::MemoryStore;
 pub use crate::metadata::BlobInfo;