Resource Owner Password Grant "must be a POST request"

[creativiii]

Hi all,

I've been trying to get a login working using the Resource Owner Password Grant oAuth, however I can't seem to make it work.

Here's my request:

const form = {
  'grant_type': 'password',
  'username': 'username',
  'password': 'pass',
  'scope': 'profile',
  'client_id': 'client_id',
}
  var formBody = [];
  for (var property in form) {
    var encodedKey = encodeURIComponent(property);
    var encodedValue = encodeURIComponent(form[property]);
    formBody.push(encodedKey + "=" + encodedValue);
  }
  formBody = formBody.join("&");
  await fetch(`https://example.com/oauth/token`, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded;charset=UTF-8'
    },
    body: formBody
  })

All I get back is an error:

{
    "error": "invalid_request",
    "error_description": "request must be a POST request"
}

Did I format this the wrong way or am I missing something? I've been following the oAuth docs but maybe I'm missing something. Any help would be appreciated!

Edited April 25, 2020 by creativiii

[bfarber]

If you monitor the HTTP request, is there a redirect occurring by chance, perhaps adding a trailing slash to /token or something?

[creativiii]

2 hours ago, bfarber said:

If you monitor the HTTP request, is there a redirect occurring by chance, perhaps adding a trailing slash to /token or something?

Turns out the problem was the missing trailing slash, just got confused by the errors and thought it was something else.