mirror of
https://github.com/nodejs/node.git
synced 2025-08-20 17:35:43 +02:00

PR-URL: https://github.com/nodejs/node/pull/51913 Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com> Reviewed-By: Richard Lau <rlau@redhat.com>
60 lines
No EOL
1.8 KiB
JavaScript
60 lines
No EOL
1.8 KiB
JavaScript
import * as os from 'node:os';
|
|
// availableParallelism available only since node v19, for older versions use
|
|
// cpus() cpus() can return an empty list if /proc is not mounted, use 1 in
|
|
// this case
|
|
/* c8 ignore start */
|
|
const defLimit = 'availableParallelism' in os
|
|
? Math.max(1, os.availableParallelism() - 1)
|
|
: Math.max(1, os.cpus().length - 1);
|
|
export const callLimit = (queue, { limit = defLimit, rejectLate } = {}) => new Promise((res, rej) => {
|
|
let active = 0;
|
|
let current = 0;
|
|
const results = [];
|
|
// Whether or not we rejected, distinct from the rejection just in case the rejection itself is falsey
|
|
let rejected = false;
|
|
let rejection;
|
|
const reject = (er) => {
|
|
if (rejected)
|
|
return;
|
|
rejected = true;
|
|
rejection ??= er;
|
|
if (!rejectLate)
|
|
rej(rejection);
|
|
};
|
|
let resolved = false;
|
|
const resolve = () => {
|
|
if (resolved || active > 0)
|
|
return;
|
|
resolved = true;
|
|
res(results);
|
|
};
|
|
const run = () => {
|
|
const c = current++;
|
|
if (c >= queue.length)
|
|
return rejected ? reject() : resolve();
|
|
active++;
|
|
const step = queue[c];
|
|
/* c8 ignore start */
|
|
if (!step)
|
|
throw new Error('walked off queue');
|
|
/* c8 ignore stop */
|
|
results[c] = step()
|
|
.then(result => {
|
|
active--;
|
|
results[c] = result;
|
|
return result;
|
|
}, er => {
|
|
active--;
|
|
reject(er);
|
|
})
|
|
.then(result => {
|
|
if (rejected && active === 0)
|
|
return rej(rejection);
|
|
run();
|
|
return result;
|
|
});
|
|
};
|
|
for (let i = 0; i < limit; i++)
|
|
run();
|
|
});
|
|
//# sourceMappingURL=index.js.map
|