prop-teststand

Server application for QRET's propulsion test stand. Discovers and communicates with ESP32 sensor/control devices over a custom binary TCP protocol, collects sensor data, controls valves, manages IP cameras, and exposes everything through a REST API and CLI.

System Architecture

The server is designed to run on any linux machine as a headless hub between ESP32 devices and any number of clients.

flowchart LR
    ESP1[ESP32<br>Sensors & Valves] -->|TCP :50000| Server
    ESP2[ESP32<br>Sensors & Valves] -->|TCP :50000| Server
    Cam[IP Cameras] -->|ONVIF / RTSP| Server

    Server[Server<br>Jetson Nano]

    subgraph Clients
      direction TB
      GUI[Desktop GUI]
      Web[Web Client]
      API[REST / WebSocket]
    end

    Server -->|FastAPI :8000| GUI
    Server -->|WebRTC / RTSP| Web
    Server -->|HTTP / WS| API

    Here((YOU ARE HERE)) --> Server:::youAreHere
    classDef youAreHere stroke:red, stroke-width:6px;
    linkStyle 5 stroke:red,stroke-width:4px
    style Here fill:transparent,stroke:none,color:red;

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Services

Service	Description
server	Main application — device discovery (SSDP), TCP listener, FastAPI, CLI, in-process log stream
media	MediaMTX RTSP/WebRTC relay for camera streams

Setup

Prerequisites

• Docker (recommended)
• Or: Python 3.12+ with uv
• Local non-Docker qlcp builds also require CMake and a C compiler

Development (Docker)

docker compose -f compose.dev.yml up

This starts all necessary services with file watching — code changes in src/ and config.yaml trigger automatic restarts.

Follow server logs with:

docker compose -f compose.dev.yml logs -f server

Production (Docker)

docker compose -f compose.prod.yml up -d

Pulls pre-built images from ghcr.io/queens-rocket-engineering-team/.

Local (No Docker)

uv sync
uv run python -m prop_teststand

uv sync installs the environment. The qlcp native library and CFFI protocol extension are rebuilt automatically during package installation. Run uv sync again to force a local protocol rebuild.

Run the mock device locally for testing with:

uv run python tests/mock_device.py

Configuration

The server reads config.yaml for service connections and camera definitions:

accounts:
  camera:
    username: propcam
    password: ...

services:
  mediamtx:
    ip: localhost
    api_port: 9997

cameras:
  - ip: 192.168.1.5
    onvif_port: 2020

Override the path with the PROP_CONFIG environment variable (defaults to ./config.yaml).

ESP32 devices configure themselves — each device sends a JSON CONFIG packet on connection describing its sensors and controls.

Running

Command	Description
uv run python -m prop_teststand	Start the main server
uv run python tests/mock_device.py	Simulate an ESP32 device for testing

Once the server is running, an interactive CLI provides commands like discover, list, stream <device> <Hz>, control <device> <name> <state>, and estop.

Protocol

Devices communicate using a custom binary protocol over TCP (port 50000) and UDP (port 50001). Devices are discovered via SSDP multicast on 239.255.255.250:1900. On discovery, the device opens a TCP connection to the server and sends its CONFIG. The server then time-syncs the device and normal operation begins (streaming, control commands, heartbeats).

For more information on protocol specifications, see ctl-qlcp-lib.

ESP32 Setup

For the microcontroller side of this project, see ctl-node-firmware.

IDE Setup

This project is intended to be opened in VSCode. Install the recommended extensions when prompted.