Knowledge Tree

A visual knowledge management system for organizing thoughts, ideas, and information in interactive tree structures.

Overview

Knowledge Tree is a self-hosted application for building and exploring hierarchical notes. It uses PHP and MySQL for persistence, with a D3.js-powered tree visualization for smooth zooming, panning, and interactive node management.

Features

• Interactive tree visualization with D3.js
• Dark dashboard with a glassmorphism-inspired UI
• Unlimited nesting depth for notes and branches
• Rich text editing with Markdown support
• Global search with Ctrl+K / Cmd+K
• Context actions for edit, add child, duplicate, and delete
• Responsive layout for desktop and mobile
• Secure authentication and prepared statements

Requirements

• PHP 8.0 or higher
• MySQL 8.0 or compatible server
• PDO MySQL extension
• Apache with mod_rewrite or another compatible web server

Installation

Local Development

1. Clone the repository:

git clone https://github.com/yourusername/knowledge-tree.git
cd knowledge-tree

2. Create a MySQL database and import the schema:

mysql -u your_user -p your_database < database.sql

3. Update config.php with your MySQL credentials.

4. Start the PHP development server:

php -S localhost:8000

5. Open http://localhost:8000 in your browser.

6. Follow the setup flow to connect the app to your database and create your account.

Shared Hosting

1. Upload the project files to your hosting account.
2. Import database.sql into your MySQL database.
3. Configure the database credentials in config.php.
4. Make sure your web server supports PHP and URL rewriting.
5. Open the site in a browser and complete the setup flow.

Project Structure

knowledge-tree/
├── index.php
├── config.php
├── setup.php
├── database.sql
├── app/
│   ├── Core/
│   │   ├── Database.php
│   │   ├── Router.php
│   │   ├── Auth.php
│   │   └── Response.php
│   ├── Controllers/
│   │   ├── AuthController.php
│   │   ├── DashboardController.php
│   │   └── ApiController.php
│   ├── Models/
│   │   ├── User.php
│   │   └── Node.php
│   └── Views/
│       ├── 404.php
│       ├── dashboard.php
│       ├── layout.php
│       ├── auth/
│       │   └── login.php
│       └── partials/
│           ├── navbar.php
│           ├── node-editor.php
│           └── sidebar.php
├── public/
│   ├── css/
│   ├── js/
│   └── assets/
└── data/

Usage

Navigation

• Click a node to view its details
• Right-click a node for edit, add child, duplicate, or delete
• Use the sidebar to browse branches
• Use the zoom controls to zoom in, zoom out, or reset the view
• Press Ctrl+K / Cmd+K to search across notes

Keyboard Shortcuts

Shortcut	Action
Ctrl+K / Cmd+K	Open search
Ctrl+S	Save current node
Escape	Close editor or menu
Delete	Remove selected node

Node Operations

• Create a root node from the toolbar or empty state
• Add a child node from the node details panel or context menu
• Edit an existing node in the modal editor
• Duplicate a node and its children
• Delete a node and its descendants

Configuration

Edit config.php to adjust your database connection and application settings.

Typical values include:

define('DB_HOST', '127.0.0.1');
define('DB_NAME', 'knowledge_tree');
define('DB_USER', 'root');
define('DB_PASS', '');
define('DB_CHARSET', 'utf8mb4');

Security

• Password hashing with bcrypt
• Prepared SQL statements
• Output escaping to prevent XSS
• Session-based authentication

Browser Support

• Chrome 90 and later
• Firefox 88 and later
• Safari 14 and later
• Edge 90 and later

License

MIT License. See the LICENSE file for details.

Credits

• D3.js - Tree visualization
• Font Awesome - Icons
• Inter - Typeface