Topics

Make non-array into an array and adjust paths

emit the header material

Get a topic associated with an anchor

Indicate we are in a single topic

Get a topic associated with a resource link ID

Get an LTI associated with a resource link ID

Check if a setting value is in a resource in a Topic

This solves the problems that (a) most LMS systems do not handle custom well for Common Cartridge Imports and (b) some systems do not handle custom at all when links are installed via ContentItem. Canvas has this problem for sure and others might as well.

The solution is to add the resource link from the Topic as a GET parameter on the launchurl URL to be a fallback:

https://../mod/zap/?inherit=assn03

Say the tool has custom key of "exercise" that it wants a default for when the tool has not yet been configured. First we check if the LMS sent us a custom parameter and use it if present.

If not, load up the LTI launch for the resource link id (assn03) in the above example and see if there is a custom parameter set in that launch and assume it was passed to us.

Sample call:

$assn = Settings::linkGet('exercise');
if ( ! $assn || ! isset($assignments[$assn]) ) {
    $rlid = isset($_GET['inherit']) ? $_GET['inherit'] : false;
    if ( $rlid && isset($CFG->topics) ) {
        $l = new Topics($CFG->topics);
        $assn = $l->getCustomWithInherit($rlid, 'exercise');
    } else {
        $assn = LTIX::ltiCustomGet('exercise');
    }
    Settings::linkSet('exercise', $assn);
}