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

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_ENCRYPTION_KEY: Base64-encoded 32-byte key used for encrypting sensitive data. If not provided, a key will be automatically generated and stored in {LEMMA_WORKDIR}/secrets/encryption_key
• LEMMA_JWT_SIGNING_KEY: Key used for signing JWT tokens. If not provided, a key will be automatically generated and stored in {LEMMA_WORKDIR}/secrets/jwt_signing_key
• 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)

Security Keys

Both the encryption key and JWT signing key are automatically generated on first startup if not provided via environment variables. The keys are stored in {LEMMA_WORKDIR}/secrets/ with restrictive file permissions (0600).

Important: Back up the secrets directory! If these keys are lost, encrypted data will become inaccessible and all users will need to re-authenticate.

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.