Struct WorkerPool 

pub struct WorkerPool<T: Send + 'static, R: Send + 'static> { /* private fields */ }

A dynamically-scaling pool of Tokio worker tasks.

Generic over:

• T — the input type passed to each work item (must be Send + 'static)
• R — the result type returned by the handler (must be Send + 'static)

Implementations

impl<T: Send + 'static, R: Send + 'static> WorkerPool<T, R>

pub fn new( config: WorkerConfig, handler: Arc<dyn Fn(T) -> BoxFuture<'static, R> + Send + Sync>, ) -> Self

Create a new pool with the given configuration and async handler function.

min_workers worker tasks are spawned immediately.

pub async fn submit(&self, item: T, priority: u8) -> Receiver<R>

Submit a work item with the given priority (higher = more urgent).

Returns a [oneshot::Receiver<R>] that resolves when processing is done. If the queue is full (bounded channel) this will apply back-pressure and await until space is available.

pub fn scale_up(&self)

Spawn one additional worker task.

pub fn scale_down(&self)

Signal one idle worker above min_workers to exit on its next idle timeout.

This is a best-effort hint; the worker may be processing an item and will only exit after completing it and then timing out.

pub async fn drain_and_shutdown(&self)

Wait for the queue to drain completely, then stop all workers.

After this method returns the pool must not be used again.

pub fn stats(&self) -> PoolStats

Return a point-in-time snapshot of pool statistics.