Struct sp_state_machine::ProvingBackend

pub struct ProvingBackend<'a, S: 'a + TrieBackendStorage<H>, H: 'a + Hasher>(_);

Patricia trie-based backend which also tracks all touched storage trie values. These can be sent to remote node and used as a proof of execution.

Implementations

impl<'a, S: 'a + TrieBackendStorage<H>, H: 'a + Hasher> ProvingBackend<'a, S, H> where
    H::Out: Codec, 

pub fn new(backend: &'a TrieBackend<S, H>) -> Self

Create new proving backend.

pub fn new_with_recorder(
    backend: &'a TrieBackend<S, H>,
    proof_recorder: ProofRecorder<H::Out>
) -> Self

Create new proving backend with the given recorder.

pub fn extract_proof(&self) -> StorageProof

Extracting the gathered unordered proof.

pub fn estimate_encoded_size(&self) -> usize

Returns the estimated encoded size of the proof.

The estimation is maybe bigger (by in maximum 4 bytes), but never smaller than the actual encoded proof.

Trait Implementations

impl<'a, S, H> Backend<H> for ProvingBackend<'a, S, H> where
    S: 'a + TrieBackendStorage<H>,
    H: 'a + Hasher,
    H::Out: Ord + Codec, 

type Error = String

An error type when fetching data is not possible.

type Transaction = S::Overlay

Storage changes to be applied if committing

type TrieBackendStorage = S

Type of trie backend storage.

fn storage(&self, key: &[u8]) -> Result<Option<Vec<u8>>, Self::Error>

Get keyed storage or None if there is nothing associated.

fn child_storage(
    &self,
    child_info: &ChildInfo,
    key: &[u8]
) -> Result<Option<Vec<u8>>, Self::Error>

Get keyed child storage or None if there is nothing associated.

fn apply_to_key_values_while<F: FnMut(Vec<u8>, Vec<u8>) -> bool>(
    &self,
    child_info: Option<&ChildInfo>,
    prefix: Option<&[u8]>,
    start_at: Option<&[u8]>,
    f: F,
    allow_missing: bool
) -> Result<bool, Self::Error>

Iterate over storage starting at key, for a given prefix and child trie. Aborts as soon as f returns false. Warning, this fails at first error when usual iteration skips errors. If allow_missing is true, iteration stops when it reaches a missing trie node. Otherwise an error is produced.

fn apply_to_keys_while<F: FnMut(&[u8]) -> bool>(
    &self,
    child_info: Option<&ChildInfo>,
    prefix: Option<&[u8]>,
    f: F
)

Retrieve all entries keys of storage and call f for each of those keys. Aborts as soon as f returns false.

fn next_storage_key(&self, key: &[u8]) -> Result<Option<Vec<u8>>, Self::Error>

Return the next key in storage in lexicographic order or None if there is no value.

fn next_child_storage_key(
    &self,
    child_info: &ChildInfo,
    key: &[u8]
) -> Result<Option<Vec<u8>>, Self::Error>

Return the next key in child storage in lexicographic order or None if there is no value.

fn for_keys_with_prefix<F: FnMut(&[u8])>(&self, prefix: &[u8], f: F)

Retrieve all entries keys which start with the given prefix and call f for each of those keys.

fn for_key_values_with_prefix<F: FnMut(&[u8], &[u8])>(
    &self,
    prefix: &[u8],
    f: F
)

Retrieve all entries keys and values of which start with the given prefix and call f for each of those keys.

fn for_child_keys_with_prefix<F: FnMut(&[u8])>(
    &self,
    child_info: &ChildInfo,
    prefix: &[u8],
    f: F
)

Retrieve all child entries keys which start with the given prefix and call f for each of those keys.

fn pairs(&self) -> Vec<(Vec<u8>, Vec<u8>)>

Get all key/value pairs into a Vec.

fn keys(&self, prefix: &[u8]) -> Vec<Vec<u8>>

Get all keys with given prefix

fn child_keys(&self, child_info: &ChildInfo, prefix: &[u8]) -> Vec<Vec<u8>>

Get all keys of child storage with given prefix

fn storage_root<'b>(
    &self,
    delta: impl Iterator<Item = (&'b [u8], Option<&'b [u8]>)>
) -> (H::Out, Self::Transaction) where
    H::Out: Ord, 

Calculate the storage root, with given delta over what is already stored in the backend, and produce a “transaction” that can be used to commit. Does not include child storage updates.

fn child_storage_root<'b>(
    &self,
    child_info: &ChildInfo,
    delta: impl Iterator<Item = (&'b [u8], Option<&'b [u8]>)>
) -> (H::Out, bool, Self::Transaction) where
    H::Out: Ord, 

Calculate the child storage root, with given delta over what is already stored in the backend, and produce a “transaction” that can be used to commit. The second argument is true if child storage root equals default storage root.

fn register_overlay_stats(&self, _stats: &StateMachineStats)

Register stats from overlay of state machine.

fn usage_info(&self) -> UsageInfo

Query backend usage statistics (i/o, memory)

fn storage_hash(&self, key: &[u8]) -> Result<Option<H::Out>, Self::Error>

Get keyed storage value hash or None if there is nothing associated.

fn child_storage_hash(
    &self,
    child_info: &ChildInfo,
    key: &[u8]
) -> Result<Option<H::Out>, Self::Error>

Get child keyed storage value hash or None if there is nothing associated.

fn exists_storage(&self, key: &[u8]) -> Result<bool, Self::Error>

true if a key exists in storage.

fn exists_child_storage(
    &self,
    child_info: &ChildInfo,
    key: &[u8]
) -> Result<bool, Self::Error>

true if a key exists in child storage.

fn as_trie_backend(&self) -> Option<&TrieBackend<Self::TrieBackendStorage, H>>

Try convert into trie backend.

fn full_storage_root<'a>(
    &self,
    delta: impl Iterator<Item = (&'a [u8], Option<&'a [u8]>)>,
    child_deltas: impl Iterator<Item = (&'a ChildInfo, impl Iterator<Item = (&'a [u8], Option<&'a [u8]>)>)>
) -> (H::Out, Self::Transaction) where
    H::Out: Ord + Encode, 

Calculate the storage root, with given delta over what is already stored in the backend, and produce a “transaction” that can be used to commit. Does include child storage updates.

fn wipe(&self) -> Result<(), Self::Error>

Wipe the state database.

fn commit(
    &self,
    _: H::Out,
    _: Self::Transaction,
    _: StorageCollection,
    _: ChildStorageCollection
) -> Result<(), Self::Error>

Commit given transaction to storage.

fn read_write_count(&self) -> (u32, u32, u32, u32)

Get the read/write count of the db

fn reset_read_write_count(&self)

Get the read/write count of the db

fn get_whitelist(&self) -> Vec<TrackedStorageKey>

Get the whitelist for tracking db reads/writes

fn set_whitelist(&self, _: Vec<TrackedStorageKey>)

Update the whitelist for tracking db reads/writes

fn proof_size(&self) -> Option<u32>

Estimate proof size

fn get_read_and_written_keys(&self) -> Vec<(Vec<u8>, u32, u32, bool)>

Extend storage info for benchmarking db

impl<'a, S: 'a + TrieBackendStorage<H>, H: 'a + Hasher> Debug for ProvingBackend<'a, S, H>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.