Struct QueryCache 

pub struct QueryCache<K, V> { /* private fields */ }

A thread-safe LRU cache with per-entry TTL expiry.

Type Parameters

• K – Key type. Must be Hash + Eq + Clone + Send + Sync.
• V – Value type. Must be Clone + Send + Sync.

Example

use std::num::NonZeroUsize;
use std::time::Duration;
use oxirs_graphrag::cache::query_cache::{QueryCache, QueryCacheConfig};

let config = QueryCacheConfig {
    capacity: NonZeroUsize::new(100).unwrap(),
    default_ttl: Duration::from_secs(60),
    ..Default::default()
};
let cache: QueryCache<String, String> = QueryCache::new(config);

cache.put("hello".to_string(), "world".to_string()).unwrap();
assert_eq!(cache.get(&"hello".to_string()).unwrap(), Some("world".to_string()));

Implementations

impl<K, V> QueryCache<K, V>

where K: Hash + Eq + Clone + Send + 'static, V: Clone + Send + 'static,

pub fn new(config: QueryCacheConfig) -> Self

Create a new QueryCache from the given configuration.

pub fn with_defaults() -> Self

Create a QueryCache with default configuration.

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

Look up key and return the value if present and fresh.

Stale entries are evicted; their keys count as misses.

pub fn put(&self, key: K, value: V) -> GraphRAGResult<()>

Insert value under key using the cache’s default TTL.

pub fn put_with_ttl( &self, key: K, value: V, ttl: Duration, ) -> GraphRAGResult<()>

Insert value under key with an explicit TTL.

The TTL is clamped to [min_ttl, max_ttl] from the config.

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

Remove an entry. Returns the value if it existed and was fresh.

pub fn evict_expired(&self) -> GraphRAGResult<usize>

Evict all stale entries and return the count of evictions.

This is O(n) in the number of entries. Call it from a periodic maintenance task to keep memory usage bounded.

pub fn stats(&self) -> GraphRAGResult<CacheStats>

Return a snapshot of cache performance statistics.

pub fn peek_entry<F, R>(&self, key: &K, f: F) -> GraphRAGResult<Option<R>>

where F: FnOnce(&CacheEntry<V>) -> R,

Peek at an entry’s metadata without affecting LRU order.

Returns None if the entry is absent or stale.

pub fn clear(&self) -> GraphRAGResult<()>

Clear all entries from the cache.

pub fn len(&self) -> GraphRAGResult<usize>

Return the current number of live (non-stale) entries.

Note: this includes any entries that might have expired between insert time and this call but have not yet been lazily evicted.

pub fn is_empty(&self) -> GraphRAGResult<bool>

Return true if the cache contains no entries.

pub fn capacity(&self) -> GraphRAGResult<usize>

Return the maximum capacity of the cache.

Trait Implementations

impl<K: Clone, V: Clone> Clone for QueryCache<K, V>

fn clone(&self) -> QueryCache<K, V>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<K, V> Debug for QueryCache<K, V>

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

Formats the value using the given formatter.