I modified the grades controller to get the overall grade, and I modified the view to display the percentages.

This further addresses issue 11.

I wrote a new query to replace the way assignments were being retrieved so that the averages could be obtained along with the rest of the assignment information.

This is to partially address issue 11.

I just committed the changes, but they aren’t live on the demo site yet, as there is still some more thorough testing to do.

This addresses Issue 13.

This is to address Issue 17.

Each entry in the database has left and right counts as well as a tag indicating whether or not it is a directory (which isn’t entirely necessary). For example, if you have a root node and two children, the database might look like this:

ID / NODE NAME / LEFT / RIGHT / DIR
1 / Root / 1 / 6 / 1
2 / Left Child / 2 / 3 / 0
3 / Right Child / 4 / 5 / 0


This requires modifying existing rows when adding new data, but given that the changing of content is a much less common occurrence than accessing data, it makes sense for the cost to be up front. This is essentially a modified preorder traversal data structure. One side effect is the queries are a bit harder to write than an adjacency list data structure. For instance, returning just the immediate child nodes of any parent node requires the following SQL query:

SELECT node.name, node.id, node.lft, node.file_name, node.file_ext, node.dir, (COUNT(parent.name) - (sub_tree.depth + 1)) AS depth
FROM section_content AS node,
section_content AS parent,
section_content AS sub_parent,
(
SELECT node.name, (COUNT(parent.name) - 1) AS depth
FROM section_content AS node,
section_content AS parent
WHERE node.lft BETWEEN parent.lft AND parent.rgt
AND node.lft = ?
AND node.section_id = ?
AND parent.section_id = ?
GROUP BY node.name
ORDER BY node.lft
)AS sub_tree
WHERE node.lft BETWEEN parent.lft AND parent.rgt
AND node.lft BETWEEN sub_parent.lft AND sub_parent.rgt
AND sub_parent.name = sub_tree.name
AND node.section_id = ?
AND parent.section_id = ?
AND node.lft != '1'
GROUP BY node.name
HAVING depth = 1
ORDER BY node.lft


Issue 15 noted that uploading course content did not work. This has been resolved for the simple case (uploading to a single section). Uploading to all sections in a course will require the addition of a loop.

This build also marks the beginning of improving non-compliant XHTML. Some elements with duplicate id’s have been classed, which is why most template files have had to be re-checked in.

Now, there is an application salt in addition to a per-user salt. The idea behind the application-wide salt is that if the database is compromised but the application data is not, it will be extremely difficult, if not impossible to generate collisions against the hashed passwords. The per-user salt is stored in the database and increases the complexity of collision-generation while not significantly affecting application performance.

You may log in as a student or teacher with the following credentials:
student / student
teacher / teacher
Database will be sanitized on a semi-regular basis.

The project is hosted here.