🦀 markdown-live-preview

A Rust-powered live Markdown preview server that integrates with Neovim via TCP.
Renders GitHub-flavored Markdown (GFM) using Comrak, served via Axum, and controlled in real time from an md-live-preview.nvim plugin.

[!NOTE] This project is designed to be paired with a Neovim plugin that streams buffer changes and cursor position.

📦 Features

Feature	Status	Notes
Live buffer preview	✅	Renders latest Markdown buffer to HTML
Cursor tracking	✅	Receives cursor position updates
Incremental updates	✅	Only sends changed lines
GFM rendering	✅	Uses `comrak` with alerts, tables, etc.
Local TCP interface	✅	Neovim pushes updates to `127.0.0.1:3001`
HTML server	✅	Axum serves preview on `http://localhost:3000`
Auto-launch browser	✅	Opens system browser on start
WebSocket live reload	🚧	Planned

🚀 Getting Started

🔧 Prerequisites

Rust (1.70+ recommended)
Neovim 0.9+
md-live-preview.nvim installed and configured

🛠 Build and run

git clone https://github.com/popplestones/markdown-live-preview
cd markdown-live-preview
cargo build --release
./target/release/markdown-live-preview

🔌 Communication Protocol

The server listens on 127.0.0.1:3001 for newline-delimited JSON messages.

✉️ Incoming message format

{
  "event": "init",
  "data": {
    "content": ["# Hello", "world!"],
    "cursor": [1, 0]
  }
}

Supported event types:

Event	Payload Structure
init	{ content: Vec, cursor: (usize, usize) }
buffer_change	{ line: usize, new_text: String }
cursor_moved	{ cursor: (usize, usize) }

[!TIP] Lines are indexed from zero.

🌍 Web Interface

URL: http://localhost:3000
Automatically opens in the default browser on launch
Reflects live updates from Neovim

🛠 Architecture

[ Neovim (plugin) ] --> TCP (127.0.0.1:3001) --> [ markdown-live-preview ]
                                              --> Axum --> HTML preview (localhost:3000)

🧪 Debugging

You can log incoming messages using:

RUST_LOG=debug ./target/release/markdown-live-preview

[!WARNING] Always restart the server if you change port bindings or encounter connection issues.

markdown-live-preview 0.1.0