Struct Singleflight 

pub struct Singleflight<T> { /* private fields */ }

Coalesce concurrent loads for the same key.

Implementations

impl<T> Singleflight<T>

pub fn new(fail_ttl: Duration) -> Self

pub fn get_ready(&self, key: &LoadKey) -> Option<Arc<T>>

pub fn contains_ready(&self, key: &LoadKey) -> bool

pub fn invalidate(&self, key: &LoadKey)

pub fn clear(&self)

pub fn ready_count(&self) -> usize

pub fn finish_load_published(&self, key: &LoadKey)

Complete a coalesced load without retaining a permanent Ready slot (JOE-1646). The caller must have already published the value into the authoritative registry. Waiters wake, see no Loading slot, and re-query the registry.

pub fn finish_load_failed(&self, key: &LoadKey, message: String)

Mark a failed coalesced load.

pub fn begin_or_wait(&self, key: &LoadKey) -> BeginLoad

Begin a coalesced load for registry-owned residency (JOE-1646).

• BeginLoad::Leader: this caller must load, insert into the registry, then call Self::finish_load_published or Self::finish_load_failed.
• BeginLoad::WaitDone: a concurrent load finished; re-check the registry.
• BeginLoad::Failed: recent failure still in TTL window.

pub fn begin_or_wait_guard( &self, key: LoadKey, ) -> Result<Option<LeaderGuard<'_, T>>, String>

Acquire leadership for key and return a panic-safe LeaderGuard.

Ok(None) means another load finished — re-check the registry. Err is a cached failure message still within TTL.

impl<T: Send + Sync + 'static> Singleflight<T>

pub fn get_or_load<F>(&self, key: LoadKey, loader: F) -> Result<Arc<T>>

where F: FnOnce() -> Result<T>,

Load key using loader exactly once for concurrent callers.

The registry mutex is not held during loader. Leader panics are converted to a failed slot so waiters never hang.

Trait Implementations

impl<T> Default for Singleflight<T>

fn default() -> Self

Returns the “default value” for a type.