LSP Multiplexer

A simple Python tool that allows multiple Language Server Protocol (LSP) servers to be multiplexed into a single LSP connection. This is useful when you want to combine the capabilities of multiple language servers - for example, using both Pyright (for type checking) and Ruff-LSP (for linting) with a single LSP client connection.

Installation

Requires Python 3.8 or higher.

git clone https://github.com/garyo/lsp-multiplexer
cd lsp-multiplexer

Usage

The multiplexer can run either over TCP or stdio:

# Run over TCP (default port 8888)
python lsp-multiplexer.py

# Run using stdio (for editors that expect LSP over stdio)
python lsp-multiplexer.py --stdio

# Run on a specific host and port
python lsp-multiplexer.py --host localhost --port 9999

Command Line Arguments

• --stdio: Use stdio instead of TCP
• --host: Host to listen on (default: 127.0.0.1)
• --port: Port to listen on (default: 8888)
• --log-level: Set logging level (DEBUG, INFO, WARNING, ERROR, CRITICAL)

Example Configuration

Edit the server configurations in lsp-multiplexer.py:

multiplexer = LSPMultiplexer([
    ["pyright-langserver", "--stdio"],    # Local process
    "tcp://localhost:8080",               # Remote server
    ["ruff-lsp"]                          # Another local process
])

Each server can be specified either as:

• A list of strings for a local process (command and arguments)
• A URL string for a remote server

Editor Configuration

Neovim Example

vim.lsp.start({
    name = 'multiplexed-python',
    cmd = {'nc', 'localhost', '8888'},  -- For TCP mode
    -- or
    cmd = {'python', 'path/to/lsp-multiplexer.py', '--stdio'},  -- For stdio mode
    root_dir = vim.fs.dirname(vim.fs.find({'pyproject.toml', 'setup.py'}, { upward = true })[1]),
})

Emacs Example

(lsp-register-client
 (make-lsp-client
  :new-connection (lsp-tcp-connection '("python" "path/to/lsp-multiplexer.py"))
  :major-modes '(python-mode)
  :server-id 'multiplexed-python))

Development

For debugging, use the --log-level DEBUG flag to see detailed logs:

python lsp-multiplexer.py --stdio --log-level DEBUG

License

MIT