SyntaxError: Unexpected token M in JSON at position 0

Here the complete error:

SyntaxError: Unexpected token M in JSON at position 0
    at JSON.parse (<anonymous>)
    at x.json (/workspace/node_modules/mailgun.js/dist/mailgun.js:2:37391)
    at processTicksAndRejections (internal/process/task_queues.js:97:5)

This is my code:

import Mailgun from 'mailgun.js';

const MAILGUN_KEY: string = functions.config().mailgun.key;
const MAILGUN_URL: string = functions.config().mailgun.url;
const MAILGUN_DOMAIN: string = functions.config().mailgun.domain;
const mailgun = new Mailgun(require('form-data'));
const mg = mailgun.client({
  username: 'api',
  key: MAILGUN_KEY,
  url: MAILGUN_URL,
});

..........

await mg.messages.create(MAILGUN_DOMAIN, {
      to: [to],
      from: `****- ****<${from}>`,
      bcc: '****@****',
      subject,
      html,
    });

I checked everything in my configuration, I have no problem with sendgrid js api so no network problem. I am using node 12, "mailgun.js": "^3.3.0",

[scaccogatto]

I see, a simple misconfiguration can bring you this kind of error. I think it should be easier to understand. I will look into the code to make this thing simpler, hope soon.

For anyone looking for an answer: check your configuration.

[SixBytesUnder]

Oh my god, it’s working! So the documentation is wrong. If you see here https://documentation.mailgun.com/en/latest/quickstart-sending.html#send-via-api and click on Node.js, you can clearly see right under the code example NOTE: If you’re sending from our EU infrastructure, be sure to substitute our EU endpoint in the above example: https://api.eu.mailgun.net/v3 So that’s what I used and assumed this is correct. Thank you @olexandr-mazepa you’re a star 🙂