Riddle

https://nkn-riddle.netlify.app/

Riddle is an open source white board collaboration App. It is built on NKN, a p2p network connectivity protocol. Hence users do not rely on a centralized authority to engage with one-another.

About

Using the App, you can create a new room and invite others by using the Share Id provided to you and start collaborating in the shared white board. The whiteboard contents can be saved to local computer by anyone in the room.

Read more here

Communication protocol

1. When a client accesses the app, a public address is allocated to him.
2. The person who creates the room (Main user) shares his public address with people who want to join.
3. When a new person joins, they ping the main user to get the latest state of the canvas and the public addresses of all the other members in the room.
4. The whiteboard updates made by each user is broadcasted to everyone so that everyone updates their board with the new changes.
5. When the main user leaves, another user is made the main user and if somebody wants to join, he has to use the public address of the new main user.

Technologies used

1. NKN
2. Fabric
3. React

The whiteboard

The whiteboard is made using Fabric.js, a very powerful and convenient layer of abstraction built over the canvas API.