Struct Metadata 

pub struct Metadata<E: Clock + Storage + Metrics, K: Array, V: Codec> { /* private fields */ }

Implementation of Metadata storage.

Implementations

impl<E: Clock + Storage + Metrics, K: Array, V: Codec> Metadata<E, K, V>

pub async fn init(context: E, cfg: Config<V::Cfg>) -> Result<Self, Error>

Initialize a new Metadata instance.

pub fn get(&self, key: &K) -> Option<&V>

Get a value from Metadata (if it exists).

pub fn get_mut(&mut self, key: &K) -> Option<&mut V>

Get a mutable reference to a value from Metadata (if it exists).

pub fn clear(&mut self)

Clear all values from Metadata. The new state will not be persisted until Self::sync is called.

pub fn put(&mut self, key: K, value: V)

Put a value into Metadata.

If the key already exists, the value will be overwritten. The value stored will not be persisted until Self::sync is called.

pub async fn put_sync(&mut self, key: K, value: V) -> Result<(), Error>

Perform a Self::put and Self::sync in a single operation.

pub fn remove(&mut self, key: &K) -> Option<V>

Remove a value from Metadata (if it exists).

pub fn keys<'a>( &'a self, prefix: Option<&'a [u8]>, ) -> impl Iterator<Item = &'a K> + 'a

Iterate over all keys in metadata, optionally filtered by prefix.

If a prefix is provided, only keys that start with the prefix bytes will be returned.

pub fn remove_prefix(&mut self, prefix: &[u8])

Remove all keys that start with the given prefix.

pub async fn sync(&mut self) -> Result<(), Error>

Atomically commit the current state of Metadata.

pub async fn close(self) -> Result<(), Error>

Sync outstanding data and close Metadata.

pub async fn destroy(self) -> Result<(), Error>

Remove the underlying blobs for this Metadata.