LTI configuration in A+¶

This section explains how LTI is configured when external content is added to an A+ course, i.e., when A+ works as the LTI Platform (or Tool Consumer in 1.1 terminology). An initial one-time setup is required: the LTI service must be enabled in the A+ site configuration before it may be used on courses.

Enabling an LTI service in the A+ site¶

Before an external LTI service may be used on any course, it must be added and enabled in the A+ site administration. The same service is enabled only once: it may then be used on any course. When the teacher adds LTI exercises or links to services in a course, they must select the LTI service to use from the enabled services in the site. Therefore, it is better to enable the LTI service in the site before adding any related course content. Some of the configuration parameters are different for LTI 1.3 and LTI 1.1, but the basic steps are same in both.

The A+ site administrator accesses the admin interface.

Find "LTI services" (for LTI 1.1) or "LTI v1.3 services" under "External services" and click "Add".
In the form, enter the launch URL of the service as well as the consumer key and secret.
The "Menu label" is the default label for the service link if any links are added to the course menu (left navigation menu). It is also used to identify the LTI service in exercise configuration, as described below. The remaining settings are different depending on whether LTI 1.3 or LTI 1.1 is used, as discussed below.

For LTI 1.3 the system administrator enters the login initiation and JWKS URLs, and client and deployment IDs. The configuration is described in more detail in the LTI 1.3 documentation for system administrators, available in the A+ Git repository.

For LTI 1.1 the "Access settings" define whether the LTI launch includes any identifiable, sensitive user data or only anonymized user data. Identifiable user data should only be sent to external services when it is really required and the legal and administrative issues concerning user data and privacy are clear. Additionally, the access settings control whether the LTI service gains access to the A+ API (application programming interface), which, for example, allows it to read user data and create submissions for the user. Usually, only LTI services developed within the A+ family know how to use the A+ API. The default value for access settings is to anonymize user data and to forbid API access.

LTI exercises and services in a course¶

LTI exercises are part of the course materials like normal exercises and chapters. LTI services may also be added to the course as links without any associated grading. Such links are displayed in the course menu (left navigation menu in the course page) and they are suitable for tools, such as forums, that typically do not involve any grading of the student's activity.

Adding LTI service links to the course menu¶

Open the "Edit course" page from the course menu (left navigation menu). It is listed under the staff menu items.
Open the "Menu" tab.
Click the "Add new menu item" button.
Enter the settings for the menu item. A menu item may link to an LTI service or to any given URL without any attached LTI parameters like a normal hyperlink. For LTI links, you must select the LTI service in the form.

The "Menu label" option indicates the title of the menu item shown in the course menu. Menu items may be grouped under headings by defining the option "Menu group label".
Submit the form.

Adding LTI exercises to a course¶

LTI exercises may be defined in the MOOC grader course configuration that is imported to the A+ course, which is the recommended way. The exercise configuration in the MOOC grader differs only a little between normal exercises and LTI exercises. LTI exercises define a few LTI-specific settings and they may ignore the grading settings as the exercise is not graded in the MOOC grader. LTI exercises may also be added manually in the A+ "Edit course" page.

Note

Note that the A+ or MOOC grader course configurations can not define the actual content of the LTI exercise. They only define how A+ connects the user to the external service (LTI Tool). It depends on the LTI Tool whether it serves ready-made learning objects or whether it provides tools for the teacher to create new exercises of a certain type.

Here is a simple example of a MOOC grader config.yaml file for an LTI exercise, for a Rubyric service that uses LTI 1.1. The 'lti' directive refers to the LTI version 1.1. If LTI 1.3 is to be used, directive 'lti1p3' should be used instead (see example below), and the respective service should be available in the LTI 1.3 services configuration as described above.

name: Submit to Rubyric
lti: Rubyric+
lti_open_in_iframe: True

The exercise is included in the course index.yaml file in the normal way. (The exercise could be defined directly in the index.yaml without a separate YAML file since there are not many settings to define.)

# a partial course index.yaml
modules:
  - key: ltiround
    name: LTI round
    children:
      - key: ltiexercise1
        category: LTI exercises
        max_points: 100
        config: exercises/lti_exercise.yaml

The LTI-specific settings for LTI 1.1 are listed in table LTI 1.1 exercise settings, and LTI 1.3 settings are shown in table LTI 1.3 exercise settings

LTI 1.1 exercise settings¶
Setting	Purpose
lti	Defines the LTI service. The value must match the menu label of an LTI service already configured in the A+ site.
lti_context_id	The context id for the LTI launch. A+ uses an id based on the course instance by default. Usually, it is best to leave this undefined in favor of the default value.
lti_resource_link_id	Resource link id for the LTI launch. A+ uses the exercise id by default. Using the default is recommended.
lti_open_in_iframe	If `True`, the exercise is opened in an iframe inside the A+ page instead of a new browser window or tab.
lti_aplus_get_and_post	If `True`, the exercise uses the A+ protocol to connect to the service. The LTI launch parameters are appended to the A+ protocol parameters. This does not work with standard LTI services. This setting is intended to be used with certain services developed within the A+ family.

LTI 1.3 exercise settings¶
Setting	Purpose
lti1p3	Defines the LTI 1.3 service. The value must match the menu label of an LTI service already configured in the A+ site.
lti_open_in_iframe	If `True`, the exercise is opened in an iframe inside the A+ page instead of a new browser window or tab.
lti_custom	LTI Tool specific custom parameters delivered to the Tool. These depend on the Tool implementation in use, and some tools may not need this field at all.

LTI exercises may be embedded in RST chapters. The exercise is defined using the normal submit RST directive with LTI-specific options. A simple example is given below. The ajax option is needed because otherwise, the chapter would break the launch of the exercise by redirecting the launch form submission to A+ instead of the correct service launch URL.

.. submit:: exercisekey 100
  :lti: Rubyric
  :lti_open_in_iframe:
  :ajax:

A definition for an embedded LTI 1.3 exercise could look as follows, for an exercise referring to a Moodle activity used as an A+ exercise.

.. submit:: moodletask 100
  :lti1p3: Moodle
  :lti_open_in_iframe:
  :lti_custom: id=ba17536e-1154-4e95-a5cb-5fd14e7b10b6
  :ajax:

Warning

Currently, A+ can not automatically update the exercise points shown in chapter or exercise pages when the student submits a new solution to the Tool. The updated points are shown when the user refreshes the web page, assuming that A+ has at that time received the new graded submission from the Tool.