Forum LAMS for Tech-Heads - General Forum: Re: Re: Integration - Single sign on questions

Thanks for posting this second message, now I think I understand this a bit clearer.

Ok, before I get into this directly, here's a bit more overall info on how the Moodle/Sakai/Blackboard/etc integrations work with Moodle.

For all the integrated packages, you can see that we have created a module *within* the LMS that we trying to integrate. So you have a LAMS Module within Sakai, Moodle and Blackboard that we have developed.

These modules basically do a few things:

1.- Work as liason between the LMS and LAMS
2.- Call the LAMS webservices to get information about sequences and classes
3.- Provide interface for LAMS Monitor and Authoring
4.- Provide the authentication for LAMS (using a hash generated on-the-fly)
5.- Provide an interface for LAMS to get basic information about users (username, first name and last name)
6.- probably some other things that I can't think of now.


The first thing that you do when you want to integration LAMS and Moodle is download the LAMS Moodle Module and add it to your existing (or new) Moodle installation following the instructions.

Also, you need to add the an entry to the LAMS database (on the LAMS side) following these instructions.

So once these two systems have all the info about each other, then the fun begins. For the sake of simplicity let's use a Moodle-LAMS example.

When a Moodle students logs in into Moodle, and wants to access a LAMS sequence, the rendering of the URL to LAMS sequencing is done dynamically. In the URL, LAMS appends a whole lot of information:

http://lamsmoodle.melcoe.mq.edu.au/lams//LoginRequest?uid=ernieg&method=learner&ts=November+16%2C2005+12%3A36+pm&sid=elche&hash=92b9e16e510b16b8f9d5d78f7541c38a8eff5656&lsid=1275&course_id=14

The uid is the user_id in Moodle.
The method is the module you are about to acces in LAMS (it is different depending of Monitor, Authoring, etc)
The ts is a date
The sid is the server_key (see the LAMS and Moodle installation instructions).
The hash is what LAMS uses for authenticating the user and verifying that he/she is coming from the right place. (this is the single sign-on mechanism we use
The course_id is the Moodle course_id

When LAMS gets all these parameters, it first checks that the hash is correct. The hash is created adding a bunch of parameters and using the secret key that both parties (LAMS and Moodle) have. If the hash is not correct, then the user will get kicked out as LAMS will understand that the user is not coming for the Moodle instance but elsewhere.

Once the hash is verified, then LAMS does the authentication and basically accepts the user request. But now LAMS has to check whether this user does actually exists on its database. So it quickly searches the uid. If it exists, then let the user go straight to the sequence. If she doesn't, then LAMS queries the LAMS-Moodle module for the basic user info, so it can create a record for her in LAMS. Once it gets the data from Moodle, creates a record and adds the user to the LAMS class (which has a in one-to-one relation to the Moodle course).

I hope that clarifies how the LMS integrations work.

Ernie

Posted by Ernie Ghiglione