Contentstore

The "contentstore" is where all course assets are stored. It's really a wrapper of code around a GridFS (MongoDB) backend and it stores binary files which can PDFs, WAVs, JPGs, or other.

Counting Assets in Each Course

If you need to find out how many assets are contained in each course, the JS below will assist you.

/* The original "group" */
db.fs.files.group( {
    key: {"_id.course": 1, "_id.org": 1, "_id.run": 1},
    reduce: function(cur, result) { result.count += 1 },
    initial: {count: 0}
} )

/* ..and with category included. */
db.fs.files.group( {
    key: {"_id.course": 1, "_id.org": 1, "_id.run": 1, "_id.category": 1},
    reduce: function(cur, result) { result.count += 1 },
    initial: {count: 0}
} )

var mapFunction = function() {
    var slicer = function(x) { return x.slice(0, x.lastIndexOf("+")) };
    var split_id = null;
    if (typeof this._id === "string")
        split_id = slicer(this._id);
    var key = [ this._id.course, this._id.org, this._id.run, this._id.category, split_id ];
    emit( key, 1 );
};
var reduceFunction = function(key, values) {
    return Array.sum(values);
}
db.fs.files.mapReduce(
    mapFunction,
    reduceFunction,
    {
        out: {inline: 1}
    }
)

/* For debugging the mapper... */
var emit = function(key, value) {
    print("emit");
    print("key: " + key + " value: " + tojson(value));
}

/* To find all courses which aren't the three specified. */
db.fs.files.find({"_id.course": {$nin : ["DemoX", "import_test", "LargeCourse101"]}})