如何在node.js中使用$ .when？ [重复]

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                        <a href="/questions/21564993/native-support-for-promises-in-node-js" dir="ltr">Native Support for Promises in Node.js</a>
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            <div class="grid--cell mb0 mt8">Closed <span title="2015-11-07 21:47:51Z" class="relativetime">4 years ago</span>.</div>
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I want to send a dynamic amount ajax requests at same time and want a callback to them all (i.e. the callback to the last one returning), but I am using node.js. I found a jquery version to solve it here Pass in an array of Deferreds to $.when() but how can I do this in node.js?

Thanks

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Answer 1

Promise.all takes an array of promises and returns a Promise of Array. The node-fetch module can be used to make HTTP requests asynchronously (AJAX only really refers to browser-executed requests.)

Bluebird is a nodejs Promise polyfill.

Something like

var fetch = require('node-fetch'),
    Promise = require('bluebird');

function fetchUrls(URLs) {
    return Promise.all(URLs.map(function (URL) {
        return fetch(URL).then(function (response) {
            return response.json();
        });
    }));
}

fetchUrls(['url1','url2']).then(function (data) {
    // do stuff with the result data here
});