Help Needed: LTI 1.3

Renato.V.657

I'm new to LTI, so I've decided to create a small application to learn more about it. However, every time I make a call to the authenticate end-point, I receive a 404 error.

This is the endpoint I'm calling from the LTI tool.

public IActionResult Login([FromForm] string iss, [FromForm] string login_hint, [FromForm] string client_id, [FromForm] string lti_message_hint)

{

  if (string.IsNullOrEmpty(iss) || string.IsNullOrEmpty(login_hint) || string.IsNullOrEmpty(client_id))

  {

    return BadRequest(new { message = "..." });

  }

  var authEndpoint = "https://{*}.desire2learn.com/d2l/lti/authenticate";


  var redirectUrl =   $"{authEndpoint}" +

                      $"?client_id={client_id}" +

                      $"&redirect_uri=https://ecplus-test.ngrok.io/api/lti/callback" +  

                      $"&response_type=id_token" +

                      $"&prompt = none" +

                      $"&scope=openid" +

                      $"&response_mode=form_post" +

                      $"&nonce=" + Guid.NewGuid().ToString() +

                      $"&login_hint={login_hint}" +

                      $"&lti_message_hint={lti_message_hint}" +

                      $"&state=" + Guid.NewGuid().ToString();


  return Redirect(redirectUrl);
}

Can anyone provide insights into what might be going wrong? Any help would be greatly appreciated.

Thank you!

Sangeetha.T.629

Hi @Renato.V.657 ,

Thanks for reaching us through the community!!

I looked into the application code you added above with the application you created in LTI advantage of Manage extensibility - ECPlus - Tunnel - Renato

I see a few configurations are missing as per the document - https://community.d2l.com/brightspace/kb/articles/23730-about-lti-1-3-launch-and-authentication . Will it be possible for you to raise a support case with all these details along with the documents referred to to create an application?

Your first step is to connect with your school or organization’s Help Desk to create a support request.   

If you’re not sure how to do this, email us at questions@community.d2l.com with the name of your school or organization and we can provide the contact details.    

If you are the ASC/ Admin for your Organization, please refer to our documentation for how to log a Support case or request, and a member of our Support team will be happy to assist you. 

Thanks,

Sangeetha

Renato.V.657

Hi @Sangeetha.T.629

Thank you for taking the time to check on that issue.

The LTI tool I use with my test is not the ECPlus - Tunnel - Renato. This one is for a different application, and this one is working fine. I'm having trouble with the ECPlus .NET 8 - Tunnel - Renato (I deactivated it because both tools share the same domain).

Could you please confirm if that one is missing something? If you need any information from me, please let me know.

Thanks,

Renato

Sangeetha.T.629

Hi @Renato.V.657 ,

Thanks for your quick response!

I reviewed the application settings for "ECPlus .NET 8 - Tunnel - Renato", and everything appears to be in order. However, we may need to investigate further to understand why your custom application is throwing a 404 error.

It would be ideal if you raise a support case with a screencast so we can track and analyze the cause more effectively.

If you have difficulties in raising a support case, please feel free to update me to raise one.

Thanks,

Sangeetha

Renato.V.657

Hi @Sangeetha.T.629

We found the issue: an extra space here

 $"&prompt = none" +

Thank you