37 lines
842 B
JavaScript
37 lines
842 B
JavaScript
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'use strict'
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module.exports = inflight
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let Bluebird
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try {
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Bluebird = require('bluebird')
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} catch (_) {
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Bluebird = Promise
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}
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const active = {}
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inflight.active = active
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function inflight (unique, doFly) {
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return Bluebird.all([unique, doFly]).then(function (args) {
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const unique = args[0]
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const doFly = args[1]
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if (Array.isArray(unique)) {
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return Bluebird.all(unique).then(function (uniqueArr) {
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return _inflight(uniqueArr.join(''), doFly)
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})
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} else {
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return _inflight(unique, doFly)
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}
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})
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function _inflight (unique, doFly) {
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if (!active[unique]) {
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active[unique] = (new Bluebird(function (resolve) {
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return resolve(doFly())
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}))
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active[unique].then(cleanup, cleanup)
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function cleanup() { delete active[unique] }
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}
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return active[unique]
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}
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}
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