Trait ChildStateBackend

pub trait ChildStateBackend<Block, Client>:
    Send
    + Sync
    + 'static
where
    Block: BlockT + 'static,
    Client: Send + Sync + 'static,
{
    // Required methods
    fn read_child_proof(
        &self,
        block: Option<Block::Hash>,
        storage_key: PrefixedStorageKey,
        keys: Vec<StorageKey>,
    ) -> Result<ReadProof<Block::Hash>, Error>;
    fn storage_keys(
        &self,
        block: Option<Block::Hash>,
        storage_key: PrefixedStorageKey,
        prefix: StorageKey,
    ) -> Result<Vec<StorageKey>, Error>;
    fn storage_keys_paged(
        &self,
        block: Option<Block::Hash>,
        storage_key: PrefixedStorageKey,
        prefix: Option<StorageKey>,
        count: u32,
        start_key: Option<StorageKey>,
    ) -> Result<Vec<StorageKey>, Error>;
    fn storage(
        &self,
        block: Option<Block::Hash>,
        storage_key: PrefixedStorageKey,
        key: StorageKey,
    ) -> Result<Option<StorageData>, Error>;
    fn storage_entries(
        &self,
        block: Option<Block::Hash>,
        storage_key: PrefixedStorageKey,
        keys: Vec<StorageKey>,
    ) -> Result<Vec<Option<StorageData>>, Error>;
    fn storage_hash(
        &self,
        block: Option<Block::Hash>,
        storage_key: PrefixedStorageKey,
        key: StorageKey,
    ) -> Result<Option<Block::Hash>, Error>;

    // Provided method
    fn storage_size(
        &self,
        block: Option<Block::Hash>,
        storage_key: PrefixedStorageKey,
        key: StorageKey,
    ) -> Result<Option<u64>, Error> { ... }
}

Child state backend API.

Required Methods

fn read_child_proof( &self, block: Option<Block::Hash>, storage_key: PrefixedStorageKey, keys: Vec<StorageKey>, ) -> Result<ReadProof<Block::Hash>, Error>

Returns proof of storage for a child key entries at a specific block’s state.

fn storage_keys( &self, block: Option<Block::Hash>, storage_key: PrefixedStorageKey, prefix: StorageKey, ) -> Result<Vec<StorageKey>, Error>

Returns the keys with prefix from a child storage, leave prefix empty to get all the keys.

fn storage_keys_paged( &self, block: Option<Block::Hash>, storage_key: PrefixedStorageKey, prefix: Option<StorageKey>, count: u32, start_key: Option<StorageKey>, ) -> Result<Vec<StorageKey>, Error>

Returns the keys with prefix from a child storage with pagination support.

fn storage( &self, block: Option<Block::Hash>, storage_key: PrefixedStorageKey, key: StorageKey, ) -> Result<Option<StorageData>, Error>

Returns a child storage entry at a specific block’s state.

fn storage_entries( &self, block: Option<Block::Hash>, storage_key: PrefixedStorageKey, keys: Vec<StorageKey>, ) -> Result<Vec<Option<StorageData>>, Error>

Returns child storage entries at a specific block’s state.

fn storage_hash( &self, block: Option<Block::Hash>, storage_key: PrefixedStorageKey, key: StorageKey, ) -> Result<Option<Block::Hash>, Error>

Returns the hash of a child storage entry at a block’s state.

Provided Methods

fn storage_size( &self, block: Option<Block::Hash>, storage_key: PrefixedStorageKey, key: StorageKey, ) -> Result<Option<u64>, Error>

Returns the size of a child storage entry at a block’s state.

Implementors