Return 对象 'ordered' with bluebird using Promise.map

Question

我有一组数字传递给 api url。它returns一个对象的答案，但问题是我想要这个对象根据原始数组排序。

这是我的代码：

var Promise = require("bluebird");
var cheerio = require('cheerio');
var request = Promise.promisifyAll(require("request"));

var numbers = ['22222', '33333', '44444'];
var obj = {};

Promise.map(numbers, function(number) {
    var options = {
        url: 'http://example.com/api',
        method: 'POST',
        form: {'number': number}
    };
    return request.postAsync(options).spread(function(response, body){
        if (response.statusCode == 200){
            var $ = cheerio.load(body);
            var link = $('script').get()[5].children[0].data;
            var regexNumber = new RegExp('<strong><h1>(.*?)</h1></strong>');
            var result = (regexNumber.exec(link)[1]);
            obj[number] = result;
        }
        else {
            console.log('Error');
        }
    });
}, {concurrency: 1}).then(function() {
    console.dir(obj);
});

这是抛出的东西：

{ '33333': 'a text',
  '44444': 'a text',
  '22222': 'a text' }

我要这样：（按原数组顺序）

{ '22222': 'a text',
  '33333': 'a text',
  '44444': 'a text' }

我也尝试过使用其他代码，同样的情况发生了：

var numbers = ['22222', '33333', '44444'];
var obj = {
    number: [],
    text:
};

var links = numbers.each(function(number) {
    var options = {
        url: 'http://example.com/api',
        method: 'POST',
        form: {'number': number}
    };
    return request.postAsync(options).spread(function(response, body){
        if (response.statusCode == 200){
            var $ = cheerio.load(body);
            var link = $('script').get()[5].children[0].data;
            var regexNumber = new RegExp('<strong><h1>(.*?)</h1></strong>');
            var result = (regexNumber.exec(link)[1]);
            obj.number.push(number);
            obj.text.push(result);
            return obj;
        }
        else {
            console.log('Error');
        }
    });
});

Promise.all(links).then(function(results) {
    results.forEach(function (data, i){
        console.log(i + ' => ' + data.number[i] + ' => ' + data.text[i]);
    });
});

一些想法？

Answer 1

您应该使用 mapSeries，它会按顺序迭代您的集合（map 不能保证，毕竟是并行的）。

var numbers = ['22222', '33333', '44444'];

Promise.mapSeries(numbers, function(number) {
    return request.postAsync({
        url: 'http://example.com/api',
        method: 'POST',
        form: {'number': number}
    }).spread(function(response, body){
        if (response.statusCode == 200){
            var $ = cheerio.load(body);
            var link = $('script').get()[5].children[0].data;
            var regexNumber = new RegExp('<strong><h1>(.*?)</h1></strong>');
            return regexNumber.exec(link)[1];
        } else {
            console.log('Error'); // throw it?
        }
    });
}).then(function(results) {
    for (var i=0; i<results.length; i++)
       console.log(i + ' => ' + numbers[i] + ' => ' + results[i]);
});

Return 对象 'ordered' with bluebird using Promise.map

Return an object 'ordered' with bluebird using Promise.map

javascript

node.js

promise

bluebird