Musique/node_modules/async.util.eachoflimit/index.js

45 lines
1.3 KiB
JavaScript

var once = require('async.util.once');
var noop = require('async.util.noop');
var onlyOnce = require('async.util.onlyonce');
var keyIterator = require('async.util.keyiterator');
module.exports = function eachOfLimit(limit) {
return function(obj, iterator, cb) {
cb = once(cb || noop);
obj = obj || [];
var nextKey = keyIterator(obj);
if (limit <= 0) {
return cb(null);
}
var done = false;
var running = 0;
var errored = false;
(function replenish() {
if (done && running <= 0) {
return cb(null);
}
while (running < limit && !errored) {
var key = nextKey();
if (key === null) {
done = true;
if (running <= 0) {
cb(null);
}
return;
}
running += 1;
iterator(obj[key], key, onlyOnce(function(err) {
running -= 1;
if (err) {
cb(err);
errored = true;
} else {
replenish();
}
}));
}
})();
};
};