Garmin Golf Connector

A small Rust CLI and library for bridging Garmin Golf launch monitor data into local simulator tooling.

The connector listens for Garmin Golf's E6 Connect / Play on PC TCP stream, normalizes each shot, exposes a local OpenAPI server, and can forward shots to GSPro or a Nova-style WebSocket feed.

Features

• Garmin Golf TCP listener for E6 Connect / Play on PC messages
• Local OpenAPI server with status, config, test-shot, Swagger UI, and OpenAPI JSON endpoints
• Optional GSPro OpenAPI TCP forwarding
• Optional Nova-style WebSocket shot stream
• Selectable host and port for every listener/output
• Reusable Rust library modules for embedding the connector in another app

Requirements

• A Garmin Golf launch monitor mode that can send E6 Connect / Play on PC data
• Optional: GSPro running with its OpenAPI connector enabled

Quickstart

Download the release archive for your OS from the GitHub Releases page:

• Linux x86_64: garmingolf-connector-linux-x86_64.tar.gz
• macOS Apple Silicon: garmingolf-connector-macos-aarch64.tar.gz
• Windows x86_64: garmingolf-connector-windows-x86_64.zip

Extract the archive, then run the connector with the default Garmin and API ports.

Linux and macOS:

./garmingolf-connector

Windows PowerShell:

.\garmingolf-connector.exe

The default listeners are:

Garmin TCP: 0.0.0.0:2483
OpenAPI:    http://127.0.0.1:5178
Swagger UI: http://127.0.0.1:5178/swagger-ui

Open Garmin Golf on your phone, choose E6 Connect / Play on PC mode, then set the PC address to the machine running this connector and the port to 2483.

Common Commands

The examples below use the Linux/macOS executable form. On Windows, use .\garmingolf-connector.exe with the same flags.

Run on a custom Garmin port:

./garmingolf-connector \
  --garmin-host 0.0.0.0 \
  --garmin-port 2483

Run the API server on a custom port:

./garmingolf-connector \
  --api-host 127.0.0.1 \
  --api-port 5178

Ask the OS for any free API port:

./garmingolf-connector --api-port 0

The CLI prints the actual bound URL at startup.

GSPro Forwarding

Enable GSPro forwarding when GSPro is listening for OpenAPI shot JSON:

./garmingolf-connector \
  --enable-gspro \
  --gspro-host 127.0.0.1 \
  --gspro-port 921

Forwarded GSPro payloads are newline-delimited JSON and include ball data plus optional club data when Garmin provides it.

Nova-Style WebSocket

Enable the WebSocket feed:

./garmingolf-connector \
  --enable-nova-ws \
  --nova-ws-host 127.0.0.1 \
  --nova-ws-port 8765

Subscribers connect to:

ws://127.0.0.1:8765/ws

Shot messages use this shape:

{
  "type": "shot",
  "shot_number": 1,
  "ball_speed_miles_per_hour": 98.5,
  "vertical_launch_angle_degrees": 13.5,
  "horizontal_launch_angle_degrees": 0.0,
  "total_spin_rpm": 2350.2,
  "spin_axis_degrees": -10.2
}

OpenAPI Server

The API server is local by default and is intended for inspection, automation, and lightweight control.

Endpoint	Method	Purpose
/health	GET	Health check
/status	GET	Current connector, Garmin, GSPro, Nova, and last-shot status
/config	GET	Effective runtime configuration
/config	PATCH	Placeholder configuration update endpoint
/shots/test	POST	Publish a synthetic shot for testing outputs
/api-docs/openapi.json	GET	OpenAPI document
/swagger-ui	GET	Swagger UI

Try a synthetic shot:

curl -X POST http://127.0.0.1:5178/shots/test

Check connector status:

curl http://127.0.0.1:5178/status

Configuration

CLI flags override environment variables. Environment variables override built-in defaults.

CLI flag	Environment variable	Default
--garmin-host	GARMINGOLF_GARMIN_HOST	0.0.0.0
--garmin-port	GARMINGOLF_GARMIN_PORT	2483
--api-host	GARMINGOLF_API_HOST	127.0.0.1
--api-port	GARMINGOLF_API_PORT	5178
--enable-gspro	GARMINGOLF_ENABLE_GSPRO	false
--gspro-host	GARMINGOLF_GSPRO_HOST	127.0.0.1
--gspro-port	GARMINGOLF_GSPRO_PORT	921
--enable-nova-ws	GARMINGOLF_ENABLE_NOVA_WS	false
--nova-ws-host	GARMINGOLF_NOVA_WS_HOST	127.0.0.1
--nova-ws-port	GARMINGOLF_NOVA_WS_PORT	8765

Boolean flags can be passed without a value or with an explicit value:

./garmingolf-connector --enable-gspro
./garmingolf-connector --enable-gspro=false

Library Use

The package exposes the garmingolf_connector library for embedding the same pieces in another Rust application.

Public modules:

• api: Axum router and OpenAPI server
• config: CLI/env configuration model
• core: shared status and shot event state
• garmin: Garmin protocol parsing and TCP runtime
• gspro: GSPro payload conversion and forwarding runtime
• nova: WebSocket shot stream

Development

Rust 1.77 or newer is required only for building from source.

Run from source:

cargo run --bin garmingolf-connector

Run the test suite:

cargo test

Check the CLI binary:

cargo check --bin garmingolf-connector

Check formatting:

cargo fmt --check

Notes

• Garmin status is modeled around the expected single Garmin app client. Multiple simultaneous Garmin clients can connect, but the top-level connection status is not a per-client view.
• GSPro and Nova outputs are optional. If neither is enabled, the connector still exposes OpenAPI status and test-shot support.

License

MIT