async/resource_pool_utils library

Async resource pool with a fixed maximum size — roadmap #666.

Bounds how many expensive-to-create resources (DB connections, HTTP clients, worker isolates) exist at once and reuses idle ones instead of recreating them. A borrower acquires a resource, uses it, and returns it; when every resource is busy, further borrowers wait FIFO until one is released. Lazily grows up to the cap — a resource is created only when a borrower needs one and none is idle.

Classes

ResourcePool<T>

A bounded, reusing pool of at most maxSize resources of type T.

Typedefs

ResourceDisposer<T> = Future<void> Function(T resource)

Disposes a pooled resource (close a socket, end a connection).

ResourceFactory<T> = Future<T> Function()

Creates a fresh pooled resource.