Proper request with async/await in Node.JS

node.jsRestAsynchronousRequestAsync Await

node.js Problem Overview


In my program I make async call for my function from another API module:

var info = await api.MyRequest(value);

Module code:

var request = require("request")

module.exports.MyRequest = async function MyRequest(value) {
    var options = {
        uri: "http://some_url",
        method: "GET",
        qs: {  // Query string like ?key=value&...
            key : value
        },
        json: true
    }
    
    try {
        var result = await request(options);
        return result;
    } catch (err) {
        console.error(err);
    }
}

Execution returns immediately, however result and therefore info contains request object and request body - info.body like key=value&..., not required response body.

What I'm doing wrong? How to fix? What is proper request usage with async, or it only works correctly with promises like mentioned here: Why await is not working for node request module? Following article mentioned it is possible: Mastering Async Await in Node.js.

node.js Solutions


Solution 1 - node.js

You need to use the request-promise module, not the request module or http.request().

await works on functions that return a promise, not on functions that return the request object and expect you to use callbacks or event listeners to know when things are done.

The request-promise module supports the same features as the request module, but asynchronous functions in it return promises so you can use either .then() or await with them rather than the callbacks that the request module expects.

So, install the request-promise module and then change this:

var request = require("request");

to this:

const request = require("request-promise");

Then, you can do:

var result = await request(options);

EDIT Jan, 2020 - request() module in maintenance mode

FYI, the request module and its derivatives like request-promise are now in maintenance mode and will not be actively developed to add new features. You can read more about the reasoning here. There is a list of alternatives in this table with some discussion of each one.

I have been using got() myself and it's built from the beginning to use promises, supports many of the same options as the request() module and is simple to program.

Solution 2 - node.js

Pretty sure you can also do the following. If what you need does not return Promise by default you can provide it via new Promise method. Above answer is less verbose though.

async function getBody(url) {
  const options = {
    url: url,
    method: 'GET',
  };

  // Return new promise
  return new Promise(function(resolve, reject) {
    // Do async job
    request.get(options, function(err, resp, body) {
      if (err) {
        reject(err);
      } else {
        resolve(body);
      }
    })
  })
}

Solution 3 - node.js

I just managed to get it to work with async/await. I wrapped it inside a function promisifiedRequest to return a promise that runs the request callback and resolves or rejects it based on error and response.

const request = require('request');

const promisifiedRequest = function(options) {
  return new Promise((resolve,reject) => {
    request(options, (error, response, body) => {
      if (response) {
        return resolve(response);
      }
      if (error) {
        return reject(error);
      }
    });
  });
};

(async function() {
  const options = {
    url: 'https://www.google.com',
    method: 'GET',
    gzip: true,
    headers: {
      'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.96 Safari/537.36'
    }
  };

  let response = await promisifiedRequest(options);
  
  console.log(response.headers);
  console.log(response.body);
})();

Solution 4 - node.js

Since request-promise has been deprecated, here are other options that don't depend on the NPM request package. got has been mentioned already, but it depends on 11 other packages. axios, in contrast, only has 1 dependency (for redirects). Everything else is natively implemented and built on top of the native NodeJS packages.

Here is the same example using axios:

const axios = require('axios')
const response = await axios.get(url)
const result = response.data

or, as a one-liner in JavaScript

const result = (await axios.get(url)).data

One-liner in TypeScript:

const {data} = await axios.get(url)

Solution 5 - node.js

For simple cases where you don't need advanced features like cookies, following redirects and retrying, you can use native http/https module to make requests:

const https = require('https')

async function fetch(url) {
  return new Promise((resolve, reject) => {
    const request = https.get(url, { timeout: 1000 }, (res) => {
      if (res.statusCode < 200 || res.statusCode > 299) {
        return reject(new Error(`HTTP status code ${res.statusCode}`))
      }

      const body = []
      res.on('data', (chunk) => body.push(chunk))
      res.on('end', () => {
        const resString = Buffer.concat(body).toString()
        resolve(resString)
      })
    })

    request.on('error', (err) => {
      reject(err)
    })
    request.on('timeout', () => {
      request.destroy()
      reject(new Error('timed out'))
    })
  })
}

const res = await fetch('https://...')

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Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionAleksey KontsevichView Question on Stackoverflow
Solution 1 - node.jsjfriend00View Answer on Stackoverflow
Solution 2 - node.jsuser3520261View Answer on Stackoverflow
Solution 3 - node.jscbdeveloperView Answer on Stackoverflow
Solution 4 - node.jsmatfaxView Answer on Stackoverflow
Solution 5 - node.jsMax IvanovView Answer on Stackoverflow