web interface for UAVCAN stuff

status: early stage

Frontend

For frontend-only development, you can use the devserver that proxies backend requests to http://kanthaus-server/.

Run

yarn dev

Then edit the files in the public directory and reload the page after.

Backend

System dependencies are:

• python3
• pip
• virtualenv (optional)
• the can driver thing (not sure the name or how to check, hopefully it's just in your kernel already)

Quickstart

Create and activate virtualenv:

virtualenv --no-site-packages env
source env/bin/activate

Install pip tools:

pip install pip-tools

Install the libraries:

pip-sync

Create a local configuration file, e.g. local_settings.ini:

[canbus]

ifname = vcan0

[node]

id = 112
name = uavcan-web-dev

Then start the dev server:

python web.py local_settings.ini

API

The application exposes an HTTP API:

GET /api/nodes

Return a list of nodes and when they were last seen, e.g.:

curl -s http://127.0.0.1:8000/api/nodes

{
  "nodes": [
    {
      "id": 100,
      "last_seen": "Thu, 03 Jan 2019 21:57:09 GMT"
    },
    {
      "id": 7,
      "last_seen": "Thu, 03 Jan 2019 21:57:09 GMT"
    }
  ]
}

GET /api/nodes/:node_id

Get information about a specific node, e.g.:

curl -s http://127.0.0.1:8000/api/nodes/6 | jq .

{
  "hardware_version": {
    "certificate_of_authenticity": "",
    "major": 0,
    "minor": 0,
    "unique_id": [
      53,
      0,
      29,
      0,
      2,
      87,
      52,
      71,
      56,
      55,
      52,
      32,
      0,
      0,
      0,
      0
    ]
  },
  "name": "K20-B Greywater pump",
  "software_version": {
    "image_crc": 0,
    "major": 0,
    "minor": 1,
    "optional_field_flags": 1,
    "vcs_commit": 151677509
  },
  "status": {
    "health": 0,
    "mode": 0,
    "sub_mode": 0,
    "uptime_sec": 122711,
    "vendor_specific_status_code": 3302
  }
}

POST /api/nodes/:node_id/:action

Make a node request, action will get uavcan. prepended to it (e.g. protocol.GetNodeInfo -> uavcan.protocol.GetNodeInfo).

JSON post data will be passed as params.

e.g.:

curl -s -XPOST http://localhost:8000/api/nodes/5/protocol.GetNodeInfo | jq .

{
  "hardware_version": {
    "certificate_of_authenticity": "",
    "major": 0,
    "minor": 0,
    "unique_id": [
      76,
      0,
      63,
      0,
      21,
      81,
      77,
      75,
      53,
      53,
      52,
      32,
      0,
      0,
      0,
      0
    ]
  },
  "name": "K20-outside thermometer",
  "software_version": {
    "image_crc": 0,
    "major": 0,
    "minor": 1,
    "optional_field_flags": 1,
    "vcs_commit": 1527198
  },
  "status": {
    "health": 0,
    "mode": 0,
    "sub_mode": 0,
    "uptime_sec": 126437,
    "vendor_specific_status_code": 3288
  }
}

Style

Run:

yapf -i web.py

Cannelloni

If you want to connect to the uavcan network from your laptop, install cannelloni then run:

sudo modprobe vcan
sudo ip link add name vcan0 type vcan
sudo ip link set dev vcan0 up
cannelloni -S c -R 192.168.178.164 -t 10000

Configuration

You can use an .ini file, or environment variables, e.g.:

[canbus]

ifname = vcan0

[node]

id = 110
name = uavcan-web-dev

Is the same as:

env var name	value
CANBUS__IFNAME	vcan0
NODE__ID	110
NODE__NAME	uvcan-web-dev

Deployment

You can run it with gunicorn like this:

gunicorn web:app

Docker

You can also run it in a docker.

First built the image:

docker build . -t uavcan-web

Then run it with some options:

docker run --init --rm -it \
  -e CANBUS__IFNAME=vcan0 \
  -e NODE__ID=110 \
  -e NODE__NAME=uavcan-web \
  --network=host \
  uavcan-web

(note: we need the --network=host to access the can interface, it means it won't have any network seperation though, there might be a way to pass it through, I didn't investigate much)

TODO

• add basic error handling
• whitelist valid actions
• make sure actions can accept the parameters via json post (didn't try it, probably doesn't quite work)