starknet_committer: define trait ForestMetadata

Author: yoavGrs

crates/starknet_committer/src/db/forest_trait.rs

@@ -1,10 +1,12 @@
 use std::collections::HashMap;
 use std::future::Future;
 
+use starknet_api::block::BlockNumber;
 use starknet_api::core::ContractAddress;
 use starknet_api::hash::HashOutput;
 use starknet_patricia::patricia_merkle_tree::node_data::leaf::LeafModifications;
 use starknet_patricia::patricia_merkle_tree::types::NodeIndex;
+use starknet_patricia_storage::storage_trait::{DbHashMap, DbKey, DbValue, Storage};
 
 use crate::block_committer::input::{ConfigImpl, StarknetStorageValue};
 use crate::forest::filled_forest::FilledForest;
@@ -13,6 +15,39 @@ use crate::forest::original_skeleton_forest::{ForestSortedIndices, OriginalSkele
 use crate::patricia_merkle_tree::leaf::leaf_impl::ContractState;
 use crate::patricia_merkle_tree::types::CompiledClassHash;
 
+pub enum ForestMetadataType {
+    CommitmentOffset,
+    StateDiffHash(BlockNumber),
+}
+
+pub trait ForestMetadata {
+    /// Returns the db key for the metadata type.
+    fn metadata_key(metadata_type: ForestMetadataType) -> DbKey;
+
+    /// Reads the metadata from the storage.
+    fn read_metadata(
+        &self,
+        storage: &mut impl Storage,
+        metadata_type: ForestMetadataType,
+    ) -> impl Future<Output = ForestResult<Option<DbValue>>> + Send {
+        async {
+            let db_key = Self::metadata_key(metadata_type);
+            Ok(storage.get(&db_key).await?)
+        }
+    }
+
+    /// Sets the metadata in the storage. Returns the previous value if it existed.
+    fn set_metadata(
+        updates: &mut DbHashMap,
+        metadata_type: ForestMetadataType,
+        value: DbValue,
+    ) -> Option<DbValue> {
+        let db_key = Self::metadata_key(metadata_type);
+        updates.insert(db_key, value)
+    }
+}
+
+
 /// Trait for reading an original skeleton forest from some storage.
 /// The implementation may depend on the underlying storage layout.
 pub trait ForestReader<'a> {

crates/starknet_committer/src/forest/forest_errors.rs

@@ -2,6 +2,7 @@ use starknet_api::core::ContractAddress;
 use starknet_patricia::patricia_merkle_tree::filled_tree::errors::FilledTreeError;
 use starknet_patricia::patricia_merkle_tree::original_skeleton_tree::errors::OriginalSkeletonTreeError;
 use starknet_patricia::patricia_merkle_tree::updated_skeleton_tree::errors::UpdatedSkeletonTreeError;
+use starknet_patricia_storage::storage_trait::PatriciaStorageError;
 use thiserror::Error;
 use tokio::task::JoinError;
 
@@ -12,6 +13,8 @@ pub enum ForestError {
     #[error(transparent)]
     OriginalSkeleton(#[from] OriginalSkeletonTreeError),
     #[error(transparent)]
+    PatriciaStorage(#[from] PatriciaStorageError),
+    #[error(transparent)]
     UpdatedSkeleton(#[from] UpdatedSkeletonTreeError),
     #[error("Couldn't create Classes Trie: {0}")]
     ClassesTrie(#[source] FilledTreeError),