Struct sc_client_db::offchain::LocalStorage

pub struct LocalStorage { /* private fields */ }

Offchain local storage

Implementations

impl LocalStorage

pub fn new(db: Arc<dyn Database<DbHash>>) -> Self

Create offchain local storage with given KeyValueDB backend.

Examples found in repository

src/lib.rs (line 1155)

	fn from_database(
		db: Arc<dyn Database<DbHash>>,
		canonicalization_delay: u64,
		config: &DatabaseSettings,
		should_init: bool,
	) -> ClientResult<Self> {
		let mut db_init_transaction = Transaction::new();

		let requested_state_pruning = config.state_pruning.clone();
		let state_meta_db = StateMetaDb(db.clone());
		let map_e = sp_blockchain::Error::from_state_db;

		let (state_db_init_commit_set, state_db) = StateDb::open(
			state_meta_db,
			requested_state_pruning,
			!db.supports_ref_counting(),
			should_init,
		)
		.map_err(map_e)?;

		apply_state_commit(&mut db_init_transaction, state_db_init_commit_set);

		let state_pruning_used = state_db.pruning_mode();
		let is_archive_pruning = state_pruning_used.is_archive();
		let blockchain = BlockchainDb::new(db.clone())?;

		let storage_db =
			StorageDb { db: db.clone(), state_db, prefix_keys: !db.supports_ref_counting() };

		let offchain_storage = offchain::LocalStorage::new(db.clone());

		let backend = Backend {
			storage: Arc::new(storage_db),
			offchain_storage,
			blockchain,
			canonicalization_delay,
			import_lock: Default::default(),
			is_archive: is_archive_pruning,
			io_stats: FrozenForDuration::new(std::time::Duration::from_secs(1)),
			state_usage: Arc::new(StateUsageStats::new()),
			blocks_pruning: config.blocks_pruning,
			genesis_state: RwLock::new(None),
			shared_trie_cache: config.trie_cache_maximum_size.map(|maximum_size| {
				SharedTrieCache::new(sp_trie::cache::CacheSize::Maximum(maximum_size))
			}),
		};

		// Older DB versions have no last state key. Check if the state is available and set it.
		let info = backend.blockchain.info();
		if info.finalized_state.is_none() &&
			info.finalized_hash != Default::default() &&
			sc_client_api::Backend::have_state_at(
				&backend,
				info.finalized_hash,
				info.finalized_number,
			) {
			backend.blockchain.update_meta(MetaUpdate {
				hash: info.finalized_hash,
				number: info.finalized_number,
				is_best: info.finalized_hash == info.best_hash,
				is_finalized: true,
				with_state: true,
			});
		}

		db.commit(db_init_transaction)?;

		Ok(backend)
	}

Trait Implementations

impl Clone for LocalStorage

fn clone(&self) -> LocalStorage

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for LocalStorage

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

Formats the value using the given formatter.

impl OffchainStorage for LocalStorage

fn set(&mut self, prefix: &[u8], key: &[u8], value: &[u8])

Persist a value in storage under given key and prefix.

fn remove(&mut self, prefix: &[u8], key: &[u8])

Clear a storage entry under given key and prefix.

fn get(&self, prefix: &[u8], key: &[u8]) -> Option<Vec<u8>>

Retrieve a value from storage under given key and prefix.

fn compare_and_set(
    &mut self,
    prefix: &[u8],
    item_key: &[u8],
    old_value: Option<&[u8]>,
    new_value: &[u8]
) -> bool

Replace the value in storage if given old_value matches the current one.