How can I save jwt token for use in the next request? in nodejs

Question

I created a login function that invokes a backend with params email and password, to receive a JWT. I have tried save the jwt value in a variable for use in the next request.

This is the method I developed, it has a post request that sends the mail and pass parameters.

async function main() {
    const data = await login("mail", "pass")
    console.log(data);
    return data
}

async function login(mail, pass) {
    const url = "https://inventario/api/login";
    var data = JSON.stringify({ "email": mail, "password": pass });

    var requestOptions = {
        method: 'POST',
        body: data,
        headers: {
            "Content-type": "application/json; charset=UTF-8"
        }
    }
    
    const response = await fetch(url, requestOptions)
    const json = await response.json()
    console.log(json)
    return json;
}

I call the function this way

var tokentest = require("./Tokentest.js");
var key = tokentest.main();
console.log(key)

Answer 1

There are multiple ways to do this depending on your final use case, but I would recommend starting by just saving it to a json file.

const fs = require('fs').promises;

// Write token to file
await fs.writeFile(path.join(__dirname, './token.json'), JSON.stringify(key));

// Use it again by reading the file and passing it to a variable
const rawData = await fs.readFile(path.join(__dirname, './token.json'), 'utf8');
const token = JSON.parse(rawData);