Struct jmt::JellyfishMerkleTree

pub struct JellyfishMerkleTree<'a, R, H: SimpleHasher> { /* private fields */ }

A Jellyfish Merkle tree data structure, parameterized by a TreeReader R and a SimpleHasher H. See crate for description.

Implementations

impl<'a, R, H> JellyfishMerkleTree<'a, R, H>

where R: 'a + TreeReader + HasPreimage, H: SimpleHasher,

pub fn get_with_ics23_proof( &self, key: Vec<u8>, version: Version ) -> Result<(Option<OwnedValue>, CommitmentProof)>

Returns the value corresponding to the specified key (if there is a value associated with it) along with an [ics23::CommitmentProof] proving either the presence of the value at that key, or the absence of any value at that key, depending on which is the case.

impl<'a, R, H> JellyfishMerkleTree<'a, R, H>

where R: 'a + TreeReader, H: SimpleHasher,

pub fn new(reader: &'a R) -> Self

Creates a JellyfishMerkleTree backed by the given TreeReader.

pub fn batch_put_value_sets( &self, value_sets: Vec<Vec<(KeyHash, OwnedValue)>>, node_hashes: Option<Vec<&HashMap<NibblePath, [u8; 32]>>>, first_version: Version ) -> Result<(Vec<RootHash>, TreeUpdateBatch)>

The batch version of put_value_sets.

pub fn put_value_set( &self, value_set: impl IntoIterator<Item = (KeyHash, Option<OwnedValue>)>, version: Version ) -> Result<(RootHash, TreeUpdateBatch)>

This is a convenient function that calls put_value_sets with a single keyed_value_set.

pub fn put_value_set_with_proof( &self, value_set: impl IntoIterator<Item = (KeyHash, Option<OwnedValue>)>, version: Version ) -> Result<(RootHash, UpdateMerkleProof<H>, TreeUpdateBatch)>

This is a convenient function that calls put_value_sets_with_proof with a single keyed_value_set.

pub fn put_value_sets( &self, value_sets: impl IntoIterator<Item = impl IntoIterator<Item = (KeyHash, Option<OwnedValue>)>>, first_version: Version ) -> Result<(Vec<RootHash>, TreeUpdateBatch)>

Returns the new nodes and values in a batch after applying value_set. For example, if after transaction T_i the committed state of tree in the persistent storage looks like the following structure:

             S_i
            /   \
           .     .
          .       .
         /         \
        o           x
       / \
      A   B
       storage (disk)

where A and B denote the states of two adjacent accounts, and x is a sibling subtree of the path from root to A and B in the tree. Then a value_set produced by the next transaction T_{i+1} modifies other accounts C and D exist in the subtree under x, a new partial tree will be constructed in memory and the structure will be:

                S_i      |      S_{i+1}
               /   \     |     /       \
              .     .    |    .         .
             .       .   |   .           .
            /         \  |  /             \
           /           x | /               x'
          o<-------------+-               / \
         / \             |               C   D
        A   B            |
          storage (disk) |    cache (memory)

With this design, we are able to query the global state in persistent storage and generate the proposed tree delta based on a specific root hash and value_set. For example, if we want to execute another transaction T_{i+1}', we can use the tree S_i in storage and apply the value_set of transaction T_{i+1}. Then if the storage commits the returned batch, the state S_{i+1} is ready to be read from the tree by calling get_with_proof. Anything inside the batch is not reachable from public interfaces before being committed.

pub fn append_value_set( &self, value_set: impl IntoIterator<Item = (KeyHash, Option<OwnedValue>)>, latest_version: Version ) -> Result<(RootHash, TreeUpdateBatch)>

Append value sets to the latest version of the tree, without incrementing its version.

pub fn put_value_sets_with_proof( &self, value_sets: impl IntoIterator<Item = impl IntoIterator<Item = (KeyHash, Option<OwnedValue>)>>, first_version: Version ) -> Result<(Vec<(RootHash, UpdateMerkleProof<H>)>, TreeUpdateBatch)>

Same as [put_value_sets], this method returns a Merkle proof for every update of the Merkle tree. The proofs can be verified using the [verify_update] method, which requires the old root_hash, the merkle_proof and the new root_hash The first argument contains all the root hashes that were stored in the tree cache so far. The last one is the new root hash of the tree.

pub fn get_with_proof( &self, key: KeyHash, version: Version ) -> Result<(Option<OwnedValue>, SparseMerkleProof<H>)>

Returns the value (if applicable) and the corresponding merkle proof.

pub fn get_with_exclusion_proof( &self, key_hash: KeyHash, version: Version ) -> Result<Result<(OwnedValue, SparseMerkleProof<H>), ExclusionProof<H>>>

Returns the value (if applicable) and the corresponding merkle proof.

pub fn get_range_proof( &self, rightmost_key_to_prove: KeyHash, version: Version ) -> Result<SparseMerkleRangeProof<H>>

Gets the proof that shows a list of keys up to rightmost_key_to_prove exist at version.

pub fn get(&self, key: KeyHash, version: Version) -> Result<Option<OwnedValue>>

Returns the value (if applicable), without any proof.

Equivalent to get_with_proof and dropping the proof, but more efficient.

pub fn get_root_hash(&self, version: Version) -> Result<RootHash>

pub fn get_root_hash_option(&self, version: Version) -> Result<Option<RootHash>>

pub fn get_leaf_count(&self, version: Version) -> Result<usize>