延迟 Node JS 中的 foreach 循环

Question

希望你一切安好。我从一个 API 获取数据并发送到 Shopify 商店 API。由于它工作正常，但是当它在循环中迭代时输入一些产品 API 忙于索引假设 0,1,2，然后索引 3,4,...10 被绕过。所以，根据我的说法，我应该将 foreach 循环延迟 10,15 秒。请帮我做这件事。我用 SETTimer 等尝试了很多次，但是对于我这个新手来说，foreach 循环结构很困难。请检查以下代码。谢谢

const request = require('request');
const { json } = require('express');
const { Parser } = require('json2csv');
const fastcsv = require('fast-csv');
//const csv = require('csv-parser');
const fs = require('fs');
const { privateDecrypt } = require('crypto');
const { time } = require('console');



const fields = ['Vendor', 'Price', 'SKU','error'];


const opts = { fields };
 
const createCsvWriter = require('csv-writer').createObjectCsvWriter;
const csvWriter = createCsvWriter({
  path: 'C:/Users/IT City/Desktop/arslan.csv',
  header: [
    {id: 'Vendor', title: 'Vendor'},
    {id: 'Price', title: 'Price'},
    {id: 'SKU', title: 'SKU'},
    {id: 'error', title: 'error'},
  ]
});

let new_products = {
  product_final: {
    Vendor: String,
    Price: String,
    SKU: String,
    Error: String,
  }
};
//////////First API from which I am getting the data

const options = {
  method: 'GET',
  url: 'https://api.dexi.io/runs/f58f7795-c11a-478c-b670-c7ae5df8677b/latest/result',
  headers: {
    accept: 'application/json',
    json: true,
    'x-dexiio-access': '9d56e967dfXXXXXXX725e234b311655c96',
    'x-dexiio-account': '5e597feb-99axxxxxxxx-37f1315723ab'
  }
};




products = ['Vendor','Price','SKU','Error']
let product = {};
request(options, function (error, response, body) {
  if (error) throw new Error(error);
  pro = JSON.parse(body);
 
/////Looping through the each Item from the first API and sending data to Shopify. But its entering only 10-12 products 
//// As handle is busy to entering the product.
/// I have to delay the foreach loop 10, 15 seconds

pro.rows.forEach(       
  
  row => { 
    
    
        for (let z = 0; z < row.length; z++) 
        {
            product[pro.headers[z]] = row[z];
            product_final2[pro.headers[z]] = row[z];
        }
         
      
        productssdata.push(product_final2)
        
        products.push(product)
       
        var Price = product.Price;
        var SKU = product.SKU;
        var Vendor = product.Vendor;
        var body_html = "THISFSDFSDFSDFSDFSFSDF";

        
            
             let new_products = {
              product: {
                title: Vendor,
                body_html: Price,
                vendor: Vendor,
                product_type: SKU,
                tags: Price
              }
            };
                    
            const options = {
            
            method: 'POST',
            url: 
            'https://0abcfsdfsdf4bb6532f3b@amjad.myshopify.com/admin/api/2020-07/products.json',
            headers: {
            accept: 'application/json',
            'apiKey': '07649cABSDCCSD8ffbae7af02',
            'password': 'sSDCSDFDF',
            body: new_products,
            json: true,
            
            };
         
          request(options, function (error, response, body) {
          
          if (error) throw new Error(error);
          console.log(body)
          
          });
          
      
          }

);



}




);

Answer 1

您不需要使用 setTimeOut() 来延迟循环。这就是 async 和 await 的用途，让我分享一个示例，如何使用 await 进行 forEach 循环延迟！！。 step1 : 返回一个带有 promise 的函数并使用 await 直到它完成。

    const wait =async props => {
    return new Promise((reslove,reject) => {
    return reslove(Math.random());       
})

}

       const x = [1,2,3,4]
       x.forEach(async number =>{
       const num = await wait();
       console.log('start')
       console.log(num);
       console.log('end');

})

Answer 2

1. 请求是deprecated
2. 无论如何都不能和await一起使用，很不方便。曾经有另一个模块 request-promise，它包装 request 并返回一个 Promise，所以可以 await 它，但它仍然被弃用。
3. 出于这些原因，请改用 Axios 或 Fetch
4. 您不能使用await 或延迟.forEach() 循环，但可以在for 循环中使用。
5. 您认为您需要延迟调用，因为它们是异步的，但实际上您应该简单地等待每个调用。使用任意超时延迟调用是一种肮脏的解决方法。

最后，您可以执行以下操作：

( async () => {

    let options = {
        url : "http://......"
    };

    const response = await axios.get(options); // Add try/catch block around this to manage errors

    const pro = response.data;

    for( let row of pro.rows) {

        options = {
            url : "http://some.other.url"
        }

        const response = await axios.get(options); // Each call will be done one by one and awaited in order
    }
})()

Answer 3

setTimeout(pro.rows.forEach((row) => {...}), 10000)

这会在 10 秒后执行 forEach。