Ripple Note

A true collaborative note taking app that supports multilevel file system, markdown editing and version control.

Website

Link

Test Account1:

• Email: [email protected]
• Password: password

Test Account2:

• Email: [email protected]
• Password: password

Table of Contents

• Feature
• Technologies

Feature

Collaborative Note Editing

• 目前不支援中文
• Supports collaboration on deletion/insertion/bulk deletion
• Supports copy (Command-C/ Ctl-C)/ paste (Command-V/ Ctl-V)/ cut (Command-X/ Ctl-X)
• Supports redo (Command-Z/ Ctl-Z)/ undo (Command-Y/ Ctl-Y)
• TODO: collaboration on Chinese characters, realtime users' cursor display

Vault -- An open sharing workspace

• Add user to vault
• Switch between vaults

File System

• Supports multilevel structure
• Real time update on file system management (drag/create/delete/rename)

Version Control

• Automatically keep track of document versions
• Restore specified version

Markdown Preview

• Change to preview mode

Technologies

Architecture

Backend

• Environment: Linux + Node.js
• Framework: Express.js
• Real-time Data Transport: Socket.IO

Front-End

• HTML
• CSS
• JavaScript
• Markdown Converter: marked.js

Operational transformation

• Breaks down text editing behavior into two kinds of operation, insertion and deletion.
• Operational transformation is, in its simplest form, a transformation function that takes a pair of operations A and B and produces a new pair A' and B' such that applying A then B' or B then A' would both lead to the same document.

• Requires a centralized server to globally order operations so that operational transformation would only take place between two parties, client and server.

Database

• RDS + MySQL
• Schema:

Networking

• Protocol: HTTP & HTTPs
• Reverse Proxy: Nginx

Tools

• Test: Mocha + Chai + Sinon
• Code Formatter: Prettier

AWS Cloud Services

• EC2
• RDS