Re: Sending additonal information to an external tool with LTI

Hi Akshay,

Firstly, there are no silly questions when it comes to either Moodle or LTI. it's great that you're exploring the capabilities of the system. It sounds like you're across the LTI specs, which is great too.

The link I provided was to the source plugins listing on the Moodle pluginsdatabase. From there, you can click a plugin (e.g. EcoHub LTI Source), then follow the "Source control URL" link to view the source. This was just an attempt at helping you see what sort of plugin code you'd need to write (i.e. what callback needs implementing, plugin structure etc.).

Regarding the naming of the custom params, it sounds like you're perhaps talking about the tool setting "Custom parameters" (a UI field found in the external tool editing form). This can be used to send custom data in the launch, but only if the data is either static (defined in that field as something like 'id=abc123'), or uses one of the predefined substitution variables supported by Moodle. Moodle doesn't provide substitution variables for plugins. Substitution variables are things like 'uname=$User.username', which will pass the username of the user across in a custom 'uname' field. There is also support for things like Course and Context fields.

In order for you to be able to send anything else (like leaderboard results, etc), you will need to create and install an lti source plugin. This is the only way to extend what can be sent in this custom data.

Hope that helps.
Jake