NodeJS execute the next process after then() [duplicate] - node.js

Question

This question already has answers here:
Using async/await with a forEach loop
(33 answers)
Closed 3 years ago.
I'm trying to do upsert inside forEach becase the request is an array of objects using Sequelize.upsert method. I do this:
async createInfo (req, res){
newsData = req.body.news,
newsList = [];
newsData.forEach(async values => {
var news = {};
news.inserted_id = values.inserted_id;
if(news.inserted_id == null){
do {
news.inserted_id = crypto.getRandom(5);
var check = await InstitutionNews.count({where: {inserted_id: news.inserted_id}});
} while (check > 0);
}
News.upsert({
institution_id: institution_id,
inserted_id: news.inserted_id,
news_date: values.news_date,
news_title: values.news_title,
description: values.news_description,
created_by: created_by
}).then(ResNews => {
news.news_date = values.news_date;
news.news_title = values.news_title;
news.description = values.news_description;
newsList.push(news);
})
})
console.log("TEST")
}
but the process stop at the then(). It didn't execute the next code like the console.log.
Is there any way to execute next line code after the then(). I need then() because I wanna push the news object into newsList array. Because I need newsList as the if else conditional to do the next process.
Thanks.

Answer 1

Since it sounds like you need to wait for forEach to complete before you do another step, so I'd suggest using something like Promise.all:
async function createInfo(req, res) {
const newsData = req.body.news
const newsList = []
try {
await Promise.all(
newsData.map(
async (values) => {
const news = {}
news.inserted_id = values.inserted_id
// ...
News.upsert({...})
.then(ResNews => {
// ...
newsList.push(news)
})
}
)
)
console.log('newsList', newList)
// do other work
} catch (error) {
// handle errors appropriately
}
}
This way, you're creating an array of promises and waiting for all of them to resolve/finish.
Your current approach with forEach won't work in this case since it won't wait for each asynchronous call to finish before executing the "next" step. Since Promise.all returns a single Promise that you can then "wait" for to resolve before continuing with your next step.
Here's a simple example that somewhat does what you're trying to do:
async function createInfo() {
const newsData = [1, 2, 3, 4, 5]
const newsList = []
await Promise.all(
newsData.map(
async (values) => {
const temp = await Promise.resolve('temp')
console.log('first async call inside values of', values)
Promise.resolve('resolved')
.then((result) => {
newsList.push(`resolved with ${values}`)
})
}
)
)
console.log('newsList after')
console.log(newsList)
}
createInfo()
EDIT
Here's an alternative solution as rightly pointed by #Bergi in the comments:
async function createInfo(req, res) {
const newsData = req.body.news
try {
const newList = await Promise.all(
newsData.map(
async (values) => {
const news = {}
news.inserted_id = values.inserted_id
// ...
// since it doesn't look like you're using any
// data that you'd get back from the `News.upsert` call, wait for
// it to finish and just simply return your `news` object
await News.upsert({...})
news.news_date = values.news_date
news.news_title = values.news_title
news.description = values.news_description
return news
}
)
)
console.log('newsList', newList)
// do other work
} catch (error) {
// handle errors appropriately
}
}

Answer 2

use await instead of then like
await News.upsert({
institution_id: institution_id,
inserted_id: news.inserted_id,
news_date: values.news_date,
news_title: values.news_title,
description: values.news_description,
created_by: created_by
});
news.news_date = values.news_date;
news.news_title = values.news_title;
news.description = values.news_description;
newsList.push(news);