Lemma

Yet another markdown editor. Work in progress

Features

• Markdown editing with syntax highlighting
• File tree navigation
• Git integration for version control
• Dark and light theme support
• Multiple workspaces
• Math equation support (MathJax)
• Code syntax highlighting

Prerequisites

• Go 1.23 or later
• Node.js 20 or later
• gcc (for go-sqlite3 package)

Configuration

Lemma can be configured using environment variables. Here are the available configuration options:

Required Environment Variables

• LEMMA_ADMIN_EMAIL: Email address for the admin account
• LEMMA_ADMIN_PASSWORD: Password for the admin account
• LEMMA_ENCRYPTION_KEY: Base64-encoded 32-byte key used for encrypting sensitive data

Optional Environment Variables

• LEMMA_ENV: Set to "development" to enable development mode
• LEMMA_DB_URL: URL (Connection string) to the database. Supported databases are sqlite and postgres a (default: "./lemma.db")
• LEMMA_WORKDIR: Working directory for application data (default: "sqlite://lemma.db")
• LEMMA_STATIC_PATH: Path to static files (default: "../app/dist")
• LEMMA_PORT: Port to run the server on (default: "8080")
• LEMMA_DOMAIN: Domain name where the application is hosted for cookie authentication
• LEMMA_CORS_ORIGINS: Comma-separated list of allowed CORS origins
• LEMMA_JWT_SIGNING_KEY: Key used for signing JWT tokens
• LEMMA_LOG_LEVEL: Logging level (defaults to DEBUG in development mode, INFO in production)
• LEMMA_RATE_LIMIT_REQUESTS: Number of allowed requests per window (default: 100)
• LEMMA_RATE_LIMIT_WINDOW: Duration of the rate limit window (default: 15m)

Generating Encryption Keys

The encryption key must be a base64-encoded 32-byte value. You can generate a secure encryption key using OpenSSL:

# Generate a random 32-byte key and encode it as base64
openssl rand -base64 32

Store the generated key securely - it will be needed to decrypt any data encrypted by the application. If the key is lost or changed, previously encrypted data will become inaccessible.

Running the backend server

1. Navigate to the server directory
2. Install dependecies: go mod tidy
3. Ensure all environment variables are set
4. Additionally set CGO_ENABLED=1 (needed for sqlite3)
5. Run the server:

   go run cmd/server/main.go
   

Running the frontend app

1. Navigate to the app directory
2. Install dependencies:

   npm install
   

3. Start the development server:

   npm start
   

   The frontend will be available at http://localhost:3000

Building for production

1. Build the frontend app:

   cd app
   npm run build
   

2. Build the backend:

   cd server
   go build -o lemma ./cmd/server
   

3. Set the LEMMA_STATIC_PATH environment variable to point to the frontend build directory
4. Run the lemma executable

Docker Support

A Dockerfile is provided for easy deployment. To build and run the Docker image:

1. Build the image:

   docker build -t lemma .
   

2. Run the container:

   docker run -p 8080:8080 -v /path/to/data:/app/data lemma
   

Upgrading

Before first stable release (1.0.0) there is not upgrade path. You have to delete the database file and start over.