Skip to main content
Sign in MENU

How Talis Aspire LTI 1.3 behaves when a VLE rolls over

Tim Hodson
  • Updated

Introduction 

This article outlines the main things to be aware of with how LTI 1.3 behaves when you roll over either your reading list or your course in a learning management system.

We set out the usual order of operational flow and the things that will trigger a rollover as being detected.

Before you read this article

You will need to establish exactly what process your organisation is using for rolling over courses in your learning management system. This will help you understand the potential effects on links to reading lists.

You will need to also establish WHEN the rollover is happening in relation to your Talis Aspire Reading Lists. We recommend drawing out a timeline of events that can help clarify when various effects might be seen and for how long.

Definitions

You might see some phrases used in this article that have very specific meanings. 

  • Course instance - By this we mean the 'thing' in the learning management system which contains all the content specific to a taught instance of a course, module or unit. Your learning management system might call this different things depending on how they have been configured.
  • context_id - This is an LTI term that means 'an identifier for the context in which the LTI link was launched' for our purposes this will usually be an identifier unique to the course instance on which the LTI link was created.
  • resource_link_id - This is an LTI term that means 'an identifier for an LTI link'. Each time an LTI link is created it gets a new resource link identifier. When the learning management system copyies an LTI link, the resource_link_id also changes
  • site_instance_id - This is an identifier set by the customer that can be passed to Talis Aspire as a custom parameter. It allows us to identify a 'site' such as a specific collection of courses. This identifier would be the same for all LTI links from the same instance.
  • deep_link_id - This is an identifier that we use to keep track of deep links that have been created by Talis Aspire. It is passed around by the VLE and seen by us and used to help trigger rollover behaviours.

Flow descriptions

Link Creation Flow

This describes a high level sequence of events that happen when you create an LTI link.

  1. A course instance is created for the first time in the learning system
    1. The course is given a context_id
  2. A link is created for the first time in the course instance
    1. The user will select content to link to BEFORE the link is created.
    2. The saved link is given a resource_link_id by the learning system
    3. The saved link selection is given:
      • a deep_link_id defined by Talis Aspire. We will use this later to determine if we have seen this link before.
      • If a context_id is present in the LTI payload, we save that with the deep_link_id
      • If a site_instance_id custom parameter is set by a system admin in the sitewide LTI custom parameters, Talis Aspire saves that alongside the context_id
      • Talis Aspire saves the identifier for the list or section that was selected.

Link Copied Flow

This describes a high level sequence of events that happen when an LTI link is copied from one course to another.

  1. A course instance is copied by the learning system
    1. The course is given a new context_id
  2. The learning system will also copy the LTI link into the new course instance
    1. The learning system will give the copied LTI link a new resource_link_id.
    2. Information from the old link will be included in the copy.
      1. This includes the deep_link_id for the original link.
  3. The site_instance_id remains unchanged unless changed manually by a system admin in the LTI tools sitewide custom parameter configuration.

Link Clicked Flow

This describes the high level sequence of events when you click an LTI link (ignoring authorisation of the LTI tool and user)

  1. When a user clicks on the LTI link
    1. The LTI Payload will tell us the resource_link_id, context_id, deep_link_id and, if set, the site_instance_id
    2. If the combination of deep_link_id, context_id and site_instance_id is found, we show the list or section that was originally selected. This could be a published or archived list.
    3. If the deep_link_id is found, but the context_id or site_instance_id have changed, this will immediately trigger a rollover detected flow which is described separately.

Rollover Detected Flow

  1. Talis Aspire will look at the list or section to see if it has been rolled over.
  2. If it has
    1. Show the user the rolled over list or section.
    2. Show the user a message saying that they are being shown the most recent rolled over list or section. This is shown every time the link is resolved.
  3. if it has not
    1. Show the user the list or section that was originally selected.
    2. This may be a published or archived list

Rollover - what will happen?

Understanding what will happen at rollover requires a lot of background information in order to determine what is happening for any given LTI link click.

You need to know what state the learning system is in. Here are some questions to help guide your analysis.

  • Is the learning system course instance copied from year A to year B?
    • Are the LTI links included in the course instance copy?
      • If LTI links are excluded then your academics will have to create brand new LTI links, so the rest of this article can be ignored! There is no way to map these automatically.
      • If LTI links are included then the context_id changing will trigger a rollover detected flow in Talis Aspire.
  • Is the whole learning system site copied from a live site to create an archived site?
    • Has the copied site had its LTI tool registered with Talis Aspire Support?
      • Although the client_id and deployment_id will stay the same, the issuer will be different. Contact Talis Support and tell them that you need to register a copy of an existing LTI tool. Include the configuration info for the existing tool, and an explanation of your learning system copy.
      • DO NOT DELETE THE LTI TOOL IN THE COPY. This is very important as it would remove all existing LTI links from the copy, and you would have to start linking them again from scratch.
      • Do not change the site_instance_id
      • LTI Links will link through to published or archived versions of the originally selected list.
    • Has the live site had the site_instance_id updated for the new year?
      • If yes, this will trigger a rollover detected flow in Talis Aspire on the live site.
      • if not then the links will continue to resolve to the same published or archived lists as before the copy.
  • Have the reading lists been archived when they are rolled over, or at a later date?
    • Archived lists will still be visible via LTI links.
    • Rollover copies of Archived lists will be detected as normal.

 

Related articles