Struct WriteThroughCache 

pub struct WriteThroughCache<S, C> { /* private fields */ }

A cache adapter that propagates writes to a backing KvStore immediately.

• put(k, v) → writes to both the cache and the store.
• get(k) → returns from cache if present; on miss, fetches from the store, populates the cache, and returns the value.
• remove(k) → removes from both cache and store.

Type parameters

• S: a KvStore implementor.
• C: a Cache<Vec<u8>, Vec<u8>> implementor.

Implementations

impl<S, C> WriteThroughCache<S, C>

where S: KvStore, C: Cache<Vec<u8>, Vec<u8>>,

pub fn new(store: S, cache: C) -> Self

Create a new write-through cache adapter.

pub fn store(&self) -> &S

Borrow the inner store.

pub fn cache(&self) -> &C

Borrow the inner cache.

pub fn get(&mut self, key: &[u8]) -> Result<Option<Vec<u8>>, StoreError>

Look up key: cache first, then store on miss.

On a store hit the value is populated back into the cache.

pub fn put(&mut self, key: Vec<u8>, value: Vec<u8>) -> Result<(), StoreError>

Insert key → value into both cache and store.

pub fn remove(&mut self, key: &[u8]) -> Result<(), StoreError>

Remove key from both cache and store.

pub fn cache_len(&self) -> usize

Return the number of live cache entries.