by Jake Dallimore.
Hi Youness,
First up, I'd like to point out that LTI 1.1 is deprecated. LTI 1.3 is the current standard that new tools should aim to support. I'm only mentioning this in case you weren't aware. It would be a shame to spend a lot of time implementing 1.1 only to find this out later.
Now, It sounds like you're having problems with the grade sync. You can do this one of several ways:
1. Using Basic Outcomes (BO) 1.0. This is the old method and uses those 2 vars you mentioned - lis_result_sourcedid and lis_outcome_service_url. http://www.imsglobal.org/specs/ltiomv1p0/specification#toc-3. This is really only used for 1.1 tools. You can check out Moodle's own enrol/lti/ code to see how it generates the payload (https://github.com/moodle/moodle/blob/1fc5c588a4742f6b05ef526100f45708084e1815/enrol/lti/classes/helper.php#L357)
2. Using Assignment and Grade Services (AGS) 2.0. https://www.imsglobal.org/spec/lti-ags/v2p0. This method only needs the user id and the grade and is much simpler. You'd normally use this method for 1.3 tools. I will note that the issue which landed this originally (MDL-60416) did test this on 1.1 tools too, but it's not something I've recently confirmed is working.
So, I'd recommend building your tool for LTI Advantage and using the AGS 2.0 method if you can.
Hope that helps
Jake
First up, I'd like to point out that LTI 1.1 is deprecated. LTI 1.3 is the current standard that new tools should aim to support. I'm only mentioning this in case you weren't aware. It would be a shame to spend a lot of time implementing 1.1 only to find this out later.
Now, It sounds like you're having problems with the grade sync. You can do this one of several ways:
1. Using Basic Outcomes (BO) 1.0. This is the old method and uses those 2 vars you mentioned - lis_result_sourcedid and lis_outcome_service_url. http://www.imsglobal.org/specs/ltiomv1p0/specification#toc-3. This is really only used for 1.1 tools. You can check out Moodle's own enrol/lti/ code to see how it generates the payload (https://github.com/moodle/moodle/blob/1fc5c588a4742f6b05ef526100f45708084e1815/enrol/lti/classes/helper.php#L357)
2. Using Assignment and Grade Services (AGS) 2.0. https://www.imsglobal.org/spec/lti-ags/v2p0. This method only needs the user id and the grade and is much simpler. You'd normally use this method for 1.3 tools. I will note that the issue which landed this originally (MDL-60416) did test this on 1.1 tools too, but it's not something I've recently confirmed is working.
So, I'd recommend building your tool for LTI Advantage and using the AGS 2.0 method if you can.
Hope that helps
Jake