user.js & artefact.js
Manage all the http requests for the application. The requests each are associated with a function from a controller because they define what request needs to be made in each call.
For example, in artefacts.js we see:
router.post('/share/add', artefactController.addViewer);
This means we will make a post request to add a viewer to an artefact whenever addViewer is called.