Struct KvShardStore 

pub struct KvShardStore { /* private fields */ }

A ShardStore that stores all state in the Cosmos KV store via Go callbacks. Gives ShardTree true lazy loading: only the data it actually accesses is read from KV.

Implementations

impl KvShardStore

pub fn new(cb: KvCallbacks) -> Self

Trait Implementations

impl ShardStore for KvShardStore

type H = MerkleHashVote

The type used for leaves and nodes in the tree.

type CheckpointId = u32

The type used to identify checkpointed positions in the tree.

type Error = KvError

The error type for operations on this store.

fn get_shard( &self, shard_root: Address, ) -> Result<Option<LocatedPrunableTree<MerkleHashVote>>, KvError>

Returns the subtree at the given root address, if any such subtree exists.

fn last_shard( &self, ) -> Result<Option<LocatedPrunableTree<MerkleHashVote>>, KvError>

Returns the subtree containing the maximum inserted leaf position.

fn put_shard( &mut self, subtree: LocatedPrunableTree<MerkleHashVote>, ) -> Result<(), KvError>

Inserts or replaces the subtree having the same root address as the provided tree.

fn get_shard_roots(&self) -> Result<Vec<Address>, KvError>

Returns the vector of addresses corresponding to the roots of subtrees stored in this store.

fn truncate_shards(&mut self, shard_index: u64) -> Result<(), KvError>

Removes subtrees from the underlying store having root addresses at indices greater than or equal to that of the specified index.

fn get_cap(&self) -> Result<PrunableTree<MerkleHashVote>, KvError>

A tree that is used to cache the known roots of subtrees in the “cap” - the top part of the tree, which contains parent nodes produced by hashing the roots of the individual shards. Nodes in the cap have levels in the range SHARD_HEIGHT..DEPTH. Note that the cap may be sparse, in the same way that individual shards may be sparse.

fn put_cap(&mut self, cap: PrunableTree<MerkleHashVote>) -> Result<(), KvError>

Persists the provided cap to the data store.

fn min_checkpoint_id(&self) -> Result<Option<u32>, KvError>

Returns the identifier for the checkpoint with the lowest associated position value.

fn max_checkpoint_id(&self) -> Result<Option<u32>, KvError>

Returns the identifier for the checkpoint with the highest associated position value.

fn add_checkpoint( &mut self, checkpoint_id: u32, checkpoint: Checkpoint, ) -> Result<(), KvError>

Adds a checkpoint to the data store.

fn checkpoint_count(&self) -> Result<usize, KvError>

Returns the number of checkpoints maintained by the data store

fn get_checkpoint_at_depth( &self, checkpoint_depth: usize, ) -> Result<Option<(u32, Checkpoint)>, KvError>

Returns the id and position of the checkpoint at the specified depth, if it exists.

fn get_checkpoint( &self, checkpoint_id: &u32, ) -> Result<Option<Checkpoint>, KvError>

Returns the checkpoint corresponding to the specified checkpoint identifier.

fn with_checkpoints<F>( &mut self, limit: usize, callback: F, ) -> Result<(), KvError>

where F: FnMut(&u32, &Checkpoint) -> Result<(), KvError>,

Iterates in checkpoint ID order over the first limit checkpoints, applying the given callback to each.

fn for_each_checkpoint<F>( &self, limit: usize, callback: F, ) -> Result<(), KvError>

where F: FnMut(&u32, &Checkpoint) -> Result<(), KvError>,

Calls the given callback for each checkpoint in CheckpointId order. This is essentially the immutable version of with_checkpoints.

fn update_checkpoint_with<F>( &mut self, checkpoint_id: &u32, update: F, ) -> Result<bool, KvError>

where F: Fn(&mut Checkpoint) -> Result<(), KvError>,

Update the checkpoint having the given identifier by mutating it with the provided function, and persist the updated checkpoint to the data store.

fn remove_checkpoint(&mut self, checkpoint_id: &u32) -> Result<(), KvError>

Removes a checkpoint from the data store.

fn truncate_checkpoints_retaining( &mut self, checkpoint_id: &u32, ) -> Result<(), KvError>

Removes checkpoints with identifiers greater than to the given identifier, and removes mark removal metadata from the specified checkpoint.