Comment 0 for bug 1943772

There is a problem in module_lti_launch.php when using SAML as parent auth

If a person does not exist they are created via create_user() function and this function will check if the auth method they are created with needs a remote username and if so adds a row to the "auth_remote_user" table too.

Then module_lti_launch.php creates a row in "auth_remote_user" table for the parent auth (SAML) if the auth method has a parent auth.

So we end up with 2 rows

But the problem is when we have a parent auth (SAML) as the parent we pass in the parent authinstance id to be the one saved in "usr" table.
So we end up with both the rows being connected to the parent auth because we pass in the parent authinstance id when creating the person.

When we then login again via LTI it finds the person by email and updates the "auth_remote_user" table but this time adds the row correctly with the LTI authinstance id.

So we end up with 3 rows - but we should only have two.