Struct SessionStoreCache 

pub struct SessionStoreCache { /* private fields */ }

LRU-bounded, thread-safe cache of open per-palace chat-session stores.

Why/What: see the module docs. Cloning is cheap — callers share one instance behind an Arc on AppState. Test: see the module-level test list.

Implementations

impl SessionStoreCache

pub fn with_max_open(max_open: usize) -> Self

Build a cache with an explicit resident-handle cap.

Why: tests force eviction with a tiny cap; operators tune production via SessionStoreCache::from_env. What: clamps max_open to at least 1 and opens an unbounded LruCache that SessionStoreCache::trim holds down to that cap. Test: tests::open_handles_are_bounded_by_cap.

pub fn from_env() -> Self

Build a cache whose cap comes from the environment.

Why: the daemon’s construction path wants the operator-tunable value. What: with_max_open(max_open_session_stores_from_env()). Test: tests::env_override_is_honoured.

pub fn capacity(&self) -> usize

The resident-handle cap this cache enforces.

Test: tests::env_override_is_honoured.

pub fn len(&self) -> usize

Number of stores currently resident (open) in the cache.

Test: tests::open_handles_are_bounded_by_cap.

pub fn is_empty(&self) -> bool

Whether no store is currently resident.

Test: tests::remove_drops_cached_handle.

pub fn get_or_open( &self, palace_id: &str, dir: &Path, ) -> Result<Arc<ChatSessionStore>>

Return the cached store for palace_id, opening it under dir on miss.

Why: the single entry point callers use, so the mutex-held open (which enforces one-store-per-palace) cannot be bypassed. What: promotes an existing entry to most-recently-used and returns it; on a miss creates dir, opens dir/chat_sessions.db (rewritten by ChatSessionStore::open to chat_sessions.redb), inserts it, then trims the cold end back to the cap. Test: tests::evicted_store_reopens_with_data_intact, tests::concurrent_callers_share_one_store.

pub fn remove(&self, palace_id: &str)

Drop the cached handle for palace_id, closing its fd if unused.

Why: palace deletion must not leave a handle pinning the inode of a directory that has just been unlinked — the exact shape of the 844 deleted-but-open handles measured in #4639. What: LruCache::pop; a no-op when the palace was never opened. If a caller still holds an Arc, that caller’s handle stays valid until it drops (Arc semantics) — the cache simply stops handing it out. Test: tests::remove_drops_cached_handle.

Trait Implementations

impl Debug for SessionStoreCache

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

Formats the value using the given formatter.

impl Default for SessionStoreCache

fn default() -> Self

Returns the “default value” for a type.