How do I make the IPFS add await wait before proceeding?

Question

Await does not wait for IPFS add function.

I am trying to add files to IPFS, then output a JSON of the file name corresponding to the HASH.

But the await just never wait and output an empty file.(Or console log an undefined)

const IPFS = require('ipfs-api');
const ipfs = new IPFS({ host: 'ipfs.infura.io', port: 5001, protocol: 'https' });
const fs = require('fs-extra'); 

const dir = 'D:/JTEST/';
let nameToHash = new Object();

function writeJSON() {
    let output= JSON.stringify(nameToHash);
    fs.writeFileSync('output.json', output);
}

async function addFile(data, filename){
    await ipfs.add(data, (err, ipfsHash) =>{
        console.log(ipfsHash);
        nameToHash[filename] = ipfsHash[0]['hash'];
    });
}

fs.readdir(dir, async (err, files) => {
    if (err)
        console.log(err);
    else {
        for(const file of files){
            let data = fs.readFileSync(dir + file);
            let a = await addFile(data, file);
            console.log(nameToHash); //writeJSON();
        }
    }
})

Answer 1

From the documentation of ipfs-api module here: https://www.npmjs.com/package/ipfs-api, I see that many functions of this module use callback style. So it's normal that await doesn't wait.

In order to use the async/await keyword, you should promisify the callback function. This article might help you understand better: https://flaviocopes.com/node-promisify/