dora_littlehand/dora_iobridge/README.md

Dora IOBridge Node

A WebSocket server that bridges web clients with the Dora dataflow for real-time voice commands and scene updates.

Inputs/Outputs

Input	Type	Description
voice_out	JSON	Response from voice control node
scene_update	JSON	Scene objects from voice control

Output	Type	Description
voice_in	string	Voice commands forwarded to Dora

Environment Variables

VOICE_HOST=0.0.0.0    # Bind address
VOICE_PORT=8765       # Listen port

Installation

cd dora_iobridge
pip install -e .

Testing

Test with WebSocket (wscat)

# Install wscat
npm install -g wscat

# Connect to the server
wscat -c ws://localhost:8765

Test with curl (websocat)

# Install websocat
# Ubuntu: sudo apt install websocat
# macOS: brew install websocat

# Send a ping
echo '{"type": "ping"}' | websocat ws://localhost:8765
# Response: {"type": "pong"}

# Send a voice command
echo '{"type": "command", "text": "sube"}' | websocat ws://localhost:8765

# Request scene refresh
echo '{"type": "scene_refresh"}' | websocat ws://localhost:8765

Test with Python

import asyncio
import websockets
import json

async def test_iobridge():
    uri = "ws://localhost:8765"
    async with websockets.connect(uri) as ws:
        # Test ping
        await ws.send(json.dumps({"type": "ping"}))
        response = await ws.recv()
        print(f"Ping response: {response}")

        # Send command
        await ws.send(json.dumps({
            "type": "command",
            "text": "agarra el cubo rojo"
        }))

        # Listen for responses
        async for message in ws:
            data = json.loads(message)
            print(f"Received: {data}")

asyncio.run(test_iobridge())

Test with curl (HTTP upgrade not supported directly)

Since WebSocket requires an upgrade handshake, use this shell script:

#!/bin/bash
# test_iobridge.sh

# Using websocat for interactive testing
websocat ws://localhost:8765 <<EOF
{"type": "ping"}
{"type": "command", "text": "sube"}
{"type": "scene_refresh"}
EOF

WebSocket Message Types

Client -> Server

Command (voice input)

{"type": "command", "text": "agarra el cubo rojo"}

Ping (health check)

{"type": "ping"}

Response: {"type": "pong"}

Scene Refresh

{"type": "scene_refresh"}

Server -> Client (Broadcasts)

Command Response

{
  "type": "response",
  "text": "Ok, voy a tomar",
  "status": "ok"
}

Scene Update

{
  "type": "scene_updated",
  "objects": [
    {
      "object_type": "cubo",
      "color": "rojo",
      "size": "big",
      "position_mm": [150.0, 200.0, 280.0],
      "source": "detection"
    }
  ]
}

Dora Dataflow Configuration

nodes:
  - id: iobridge
    build: pip install -e ./dora_iobridge
    path: dora_iobridge
    inputs:
      voice_out: voice_control/voice_out
      scene_update: voice_control/scene_update
    outputs:
      - voice_in
    env:
      VOICE_HOST: "0.0.0.0"
      VOICE_PORT: "8765"

dora up
dora start dataflow.yml

Dependencies

• dora-rs >= 0.3.9
• pyarrow >= 12.0.0
• websockets >= 12.0