Textnow API Errors when logging in through a script - json

Question

When trying to log into textnow through an API using the correct username and password, the following error occurs:
UnhandledPromiseRejectionWarning: Error: 401 Unauthorized
at _response.transport.request.then (E:\nodejs\node_modules\snekfetch\src\index.js:193:21)
at process._tickCallback (internal/process/next_tick.js:68:7)
(node:19732) UnhandledPromiseRejectionWarning: Unhandled promise rejection.
This error originated either by throwing inside of an async function without
a catch block, or by rejecting a promise which was not handled with .catch().
(rejection id: 2)
Here's a look at the code from the API that I'm using:
module.exports.textnowLogin = (email, password) => {
return new Promise((resolve, reject) => {
let json = { "password": password, "username": email };
let queryEndpoint = "sessions?client_type=TN_ANDROID";
let signature = md5(`${tnSignatureKey}POST${queryEndpoint}${JSON.stringify(json)}`);
snekfetch.post(`https://api.textnow.me/api2.0/${queryEndpoint}&signature=${signature}`)
.set("Content-Type", "application/json")
.send(json)
.then((result) => {
return resolve(result.body);
}).catch(reject);
});
};
Here's a look at how I use this method in my js file:
const textNow = require('textnow-api');
textNow.login(username, password).then(client => {
console.log(`Logged in as ${client.username}`);
});`
This definitely has to be a server side issue, no? Something must be going wrong on Textnow's end. What can I do to circumvent this?
EDIT: const snekfetch = require("snekfetch"),
md5 = require("md5"),
tnSignatureKey = "f8ab2ceca9163724b6d126aea9620339";
Where did this key originate from? Perhaps if a new one was generated then the authorization error would be solved?
As a side note, another potential issue could be the client_type being set to ANDROID, and I am trying to use an iOS account to login. However, whenever I try using an Android account to log in instead, I get a 400 Bad Request, like Textnow does not recognize the account's credentials.

Answer 1

There may be other errors in the code, but the first mistake is the creation of an extra promise. Here's a version of the code that solves that and should either work or be simpler to debug...
module.exports.textnowLogin = (email, password) => {
let json = { "password": password, "username": email };
let queryEndpoint = "sessions?client_type=TN_ANDROID";
let signature = md5(`${tnSignatureKey}POST${queryEndpoint}${JSON.stringify(json)}`);
let url = `https://api.textnow.me/api2.0/${queryEndpoint}&signature=${signature}`;
return snekfetch.post(url).set("Content-Type", "application/json").send(json).then(result => {
return result.body;
});
};