resource-pooler

Resource-Pooler

The minimal, lock-free library for managing shared access to resources.

Use cases:

• Worker Pools
• Request Throttling
• Task Queues

Distribution Strategy

Resources are assigned on a FIFO (first in, first out) basis:

1. The caller that requested a resource first will be assigned the first available resource
2. The resource that first becomes available will be the first to be assigned

Guarantees

1. No two callers will be able to access the same resource concurrently (as long as the API is respected)
2. Each caller will eventually be assigned a resource (as long as one eventually becomes available)

API

ResourcePooler

Constructor accepts a factory to manage the creation, disposal and access to resources.

See below for examples.

createPool()

Helper function to create a pre-sized pool.

async function createPool(factory, size = 8) {
    const pooler = new ResourcePooler({ factory });
    await pooler.resize(size);
    return pooler;
}

Examples

Worker Pooling

Sample usage

const workerPool = await createPool({
    create() {
        return new Worker(require.resolve('./Worker.js'))
    },
    async dispose(worker) {
        await worker.terminate()
    },
})

workerPool.use((worker) => {
    worker.postMessage({
        message: "Hello World!"
    })
    return new Promise((resolve, reject) => {
        worker
          .once('message', (content) => {
            resolve(content)
          })
          .once('error', (error) => reject(error))
    })
})