Architecture

Architecture of the ASQ app

The ASQ app utilizes websockets to transfer events between connected clients and the server. The basic entitities of the app are:

• User
• Slideshow
• Question
• Session
• Stats

In the following sections we present the architecture of the basic entities of ASQ

Database Schema

Entities

User

* *name* : `String` Name of the user (must be unique). * *password* : `String` (Password, stored as plain text...) * *email* : `String` Email of the user. * *slides* : `[ObjectId]` References to all the slides in the db owned by the user. * *current* : `ObjectId` Reference to the current session hosted to the user. (Defaults to `null`).

Slideshow

* *title* : `String` Title of the slideshow * *course* : `String` Used for categorization (Max please confirm!) (Defaults to `General`) * *owner* : `ObjectId` Reference to the owner of the slideshow. * *questions* : `[ObjectId]` References to the questions related to the slideshow. * *links* : `[String]` : Links to be included with the slideshow in the head part of the page. (For css and such.)

Question

Session

* *presenter* : `ObjectId` Reference to the user in control of the session. * *slides* : `ObjectId` Reference to the slides used in the session. * *activeSlide* : `String` Id of the current slide (ids are generated by impress.js), defaults to `'0'`. * *date* : `Date` Date of the session. Default to the date of creation. * *viewers* :`[String]` Keep track of the nicknames of viewers as string * *answers* :`[ObjectId]` Store the id of the answers submitted by viewers. (Ansers are stored in a different db.) * *showingQuestion* : `Boolean` Indicates the state of a question popup. * *showingAnswer* : `Boolean` Indicates the state of a answer popup. * *nextQuestion* : `Boolean (Virtual)` Indicates if there is a question after the current slide. * *path* : `String` (Virtual) Returns the path to the folder containing the slides.

Stats

Implementation Details

WebSockets

Websockets connect immediately once the page is loaded. Admin sockets should be authenticated.

Events

• viewer : Emitted by a viewer when he first joins the folo namespace.
• admin : Emitted by an admin when he first joins the ctrl namespace.
• impress:start : Emitted by an admin when he hides the welcome popup and starts the presentation. Sent to all namespaces.
• goto : Emitted by an admin when he moves to a slide. Re-transmitted to all namespaces.
  If there is a question, a question event is transmitted instead.
• question : Emitted from the ctrl namespace when a question needs to be displayed.
• show:answer Emitted to ctrl namespace when then answer needs to be displayed.
  If a answer can be displayed, a answer event is transmitted to all namespaces.
• answer Emitted from ctrl to all namespaces. Indicates a popup answer must be displayed.
• hide Emitted from ctrl to all namespaces. Indicates a popup answer must be hidden.
• submit Emitted by followers (in the folo namespace) when a follower submits his answer to a question.

Routes

• /live/:user : Verb: GET Follow a live presentation from user :user.
• /admin : Verb: GET Control your live presentation.
• /upload : Verb: POST Upload a presentation archive. (The archive must be located at req.files.upload)
• /start/:id : Initialize a new session with the slides matching id, providing the authentificated use matches the owner of the slides.

Use absolute path to serve files from the public folder. For example to serve the file style.css in the css folder in public,
the path should be /css/style.css and not css/style.css.

Reserved internal routes

The following routes are reserved and used for the websocket traffic.

• /ctrl : Used to control the presentation, (ie. To emit goto events and such.) require authentification
• /folo : Used to follow a presentation, receive goto events and submit answers to questions and such.