Add completed method in Pool

[10n37]

Instead of doing every time this:

const pool = workerpool.pool(
    path.resolve(__dirname, 'worker')
)
const tasks: workerpool.Promise<any, Error>[] = []

for (const entity of entities) {
 const task = pool.exec('worker', [entity])
 tasks.push(task)
}

await Promise.all(tasks)
await pool.terminate()

We can do:

const pool = workerpool.pool(
    path.resolve(__dirname, 'worker')
)

for (const entity of entities) {
 pool.exec('worker', [entity])
}

/* Wait all tasks to complete */ 
await pool.completed()
await pool.terminate()

It would be very handy, if this method is added in the future
For example, threads.js already have this feature

[josdejong]

Thanks for your suggestion. Actually, what you want is already there: just calling await pool.terminate() will by default gracefully shutdown the workerpool. It finishes all running tasks and does not accept new tasks.

From the docs:

Pool.terminate([force: boolean [, timeout: number]])

If parameter force is false (default), workers will finish the tasks they are working on before terminating themselves. Any pending tasks will be rejected with an error 'Pool terminated'. When force is true, all workers are terminated immediately without finishing running tasks. If timeout is provided, worker will be forced to terminate when the timeout expires and the worker has not finished.

Docs: https://github.com/josdejong/workerpool#api

[10n37]

Thanks for your suggestion. Actually, what you want is already there: just calling await pool.terminate() will by default gracefully shutdown the workerpool. It finishes all running tasks and does not accept new tasks.

From the docs:

Pool.terminate([force: boolean [, timeout: number]])
If parameter force is false (default), workers will finish the tasks they are working on before terminating themselves. Any pending tasks will be rejected with an error 'Pool terminated'. When force is true, all workers are terminated immediately without finishing running tasks. If timeout is provided, worker will be forced to terminate when the timeout expires and the worker has not finished.

Docs: https://github.com/josdejong/workerpool#api

Wow, i tried. But it works not as expected. In this code pool terminated first. Tasks not executing.

const pool = workerpool.pool(
    path.resolve(__dirname, 'worker')
)

for (const entity of entities) {
 pool.exec('worker', [entity])
}

await pool.terminate()

[josdejong]

Ooo wait a second, of course: terminate only gracefully finishes all running tasks, but it will cancel and not execute queued tasks. Sorry, my bad.

So, yes, your suggestion makes sense, a method like await pool.completed(). Anyone interested in thinking this through and implementing such a method?

[Darshan-upadhyay1110]

await pool.completed().then(result=>{ await pool.terminate(); })
is it the way we can do this ?

[josdejong]

Yes, you can keep track on all tasks and wait till they are all resolved, like the first example in #354 (comment). It's a bit cumbersome but not a showstopper.