OAuth 2 Troubleshooting

Troubleshooting

On the 'OAuth 2 services' page, there is a red cross for 'Allow login'

To get a green tick for Allow login, edit the OAuth 2 service and make sure that the setting 'Show on login page' is ticked.

I obtain a coding error after enabling OAuth 2 authentication

Have you any OAuth 2 plugins for earlier versions installed on your site? If so, you will need to uninstall them in order to use the standard OAuth 2 authentication.

I obtain an error message when attempting to log in using Facebook

The error message 'The user information returned did not contain a username and email address. The OAuth 2 service may be configured incorrectly.' is most likely because the user's Facebook account was created using a mobile number.

The solution is for the user to first log in to Facebook and add a username and email address there.

I see a "required paramenter (code) was missing" error after logging into the OAuth 2 service

The error message 'A required parameter (code) was missing' can be caused by a mis-configured webserver. OAuth 2 relies on long tokens passed as url parameters, and some webserver configurations will prevent this from working. See http://www.php.net/manual/en/reserved.variables.get.php#101469 for one possible solution.

I have all green checkmarks on my /admin/tool/oauth2/issuers.php page for Google & Facebook but no buttons show on my servers login page

It was discovered that in a fresh install of Moodle 3.4 (probably for security reasons) that the plugin configuration for OAuth2 was in a disabled state. Go to your page for Site Administration - Plugins - Authentication - Manage authentication (/admin/settings.php?section=manageauths), and enable the record for OAuth2, then optionally tweak your settings for that record.