Zipping-files.js

this.httpServer.get('/files/download/:organization/course/:course/class/:class', function(req, res){
	var zip = zipstream.createZip({ level: 1 });

	res.setHeader('Content-disposition', 'attachment; filename=' + req.params.course);

	zip.on('data', function(data){
		res.write(data);
	});

	Files.find({
		organization: req.params.organization,
		course: req.params.course,
		class: req.params.class
	}).exec(function (err, data) {
		var files = data.map(function(item){
			var file = new File(item);

			return function(callback){
				zip.addFile(fs.createReadStream( file.location() ), { name: file.name }, function() {
					callback(null, true);
				});
			};
		});

		async.series(files, function(err, results){
			zip.finalize(function(written) {
				res.end();
			});
		});
	});
});