friend0/meshcat-go

Meshcat with Go using NATS.io and Echo.

meshcat-go

A golang interface to meshcat, a small application for running three.js applications. The motivation for this project is to demonstrate networked simulations for robotics, using the NATS.io message middleware as the communication layer. NATS has clients in just about every major language, and also interfaces with MQTT. It is performant, and has top tier tooling to support development. go-meshcat implements a Go backend for serving the application bundle in production, as well as the NATS server. The basic workflow is that the backend Echo serves the client JS bundle on the main route /. Echo also runs a Websocket server that the client connects to when it's loaded. In addition, the backend hosts subscriptions to meshcat topics that map to the commands implemented in the meshcat frontend. When the nats service for a particular topic gets a new message, it uses the web socket connection to proxy the request to the client. Note that it may be possible in a future implementation for most of the nats processing to happen on the client.

There are some rudimentary development flows in place with hot reloading on air (Go) and the webpack (frontend) sides of the house. I will add deployment tooling eventually. There are some basic stack commands provided in the Makefile.

This work is heavily inspired by meshcat and meshcat-python, and depends on the bootstrapped three.js application contained therein.

Getting Started

Watch this section for updates on how to run the app.

• Basic dev requirements: docker, go
• Install Air, Webpack

Development

Use nats-server to launch a local NATS server if you're not running this against the production NATS server on sunset. Run the backend with air at the root of this repo. Run the frontend development server with npx webpack serve, in the web/meshcat directory. The server should now be running at http://localhost:8081. Note that this is where the webpack dev server is hosting the frontend bundle. The backend is actually running on http://localhost:8080. The former is the live bundle, and proxies to the backend via settings configured in webpack. The latter is the backend, which will serve the bundle that was built at runtime.

TODO:

• reorganize around a frontend/backend structure.
• refactor frontend to be more modular. It's currently one long main file.
• implement htmx view window with some input features