barnowl-noble

barnowl-noble collects data from ambient Bluetooth Low Energy devices using the noble BLE Central module for Node.js, transforming it into standard developer-friendly JSON that is vendor/technology/application-agnostic.

barnowl-noble is a lightweight Node.js package that can run on resource-constrained edge devices. It can forward data to reelyActive's Pareto Anywhere open source middleware suite, and can just as easily be run standalone behind a barnowl instance, as detailed in the code examples below.

barnowl-noble vs. barnowl-hci

barnowl-noble and barnowl-hci are similar in functionality in that they both collect ambient Blutooth Low Energy data, however each implements a different role:

• barnowl-noble implements the Central role
• barnowl-hci implements the Observer role

Use barnowl-noble when data must be collected by connecting to peripherals and interacting with their characteristics (see Supported Services and Peripheral Devices below).

Use barnowl-hci when data is to be collected from advertising packets alone.

Do not use barnowl-noble and barnowl-hci on the same Bluetooth adapter simultaneously.

Pareto Anywhere Integration

A common application of barnowl-noble is to collect Bluetooth Low Energy device data for pareto-anywhere using an onboard BLE radio or adapter. Simply follow our Create a Pareto Anywhere startup script tutorial using the script below:

#!/usr/bin/env node

const ParetoAnywhere = require('../lib/paretoanywhere.js');

// Edit the options to customise the server
const BARNOWL_NOBLE_OPTIONS = {};

// ----- Exit gracefully if the optional dependency is not found -----
let BarnowlNoble;
try {
  BarnowlNoble = require('barnowl-noble');
}
catch(err) {
  console.log('This script requires barnowl-noble.  Install with:');
  console.log('\r\n    "npm install barnowl-noble"\r\n');
  return console.log('and then run this script again.');
}
// -------------------------------------------------------------------

let pa = new ParetoAnywhere();
pa.barnowl.addListener(BarnowlNoble, {},
                       BarnowlNoble.DefaultListener, BARNOWL_NOBLE_OPTIONS);

Alternative Integration

barnowl-noble also includes a script to forward data to a local Pareto Anywhere instance as UDP raddecs with target localhost:50001. Start this script with the command:

npm run forwarder

To instead forward UDP raddecs to a remote Pareto Anywhere instance, start this script with the command:

npm run forwarder xxx.xxx.xxx.xxx

where xxx.xxx.xxx.xxx is the IP address of the remote instance.

Note: Any GATT data collected by barnowl-noble will be lost using this approach as protocolSpecificData is not currently supported in UDP-encoded raddecs.

Quick Start

Clone this repository and install package dependencies with npm install. If installation fails on your system, validate these installation requirements.

Then from the root folder run at any time:

npm start

If you observe a permissions error (ex: EPERM), either assign the necessary privileges (recommended) or run as root (not recommended). barnowl-node will set the local Bluetooth radio to scan and print any processed raddec data to the console.

Supported Services and Peripheral Devices

barnowl-noble supports the following Bluetooth services and peripheral devices:

| Service UUID | Peripheral devices | |:-------------------------------------|:--------------------| | 1c930001-d459-11e7-9296-b8e856369374 | Sensor-Works BluVib |

Assigning Privileges

If required, assign the necessary privileges for Node.js to initiate a HCI scan on the given OS with the command:

npm run privileges

On Linux systems (such as the Raspberry Pi) this will run the following command to grant cap_net_raw privileges so that any Linux user may start a scan.

sudo setcap cap_net_raw+eip $(eval readlink -f `which node`)

Installation Requirements

barnowl-noble depends on the noble package which does not support all operating systems. If your OS is supported but a precompiled binary does not exist, npm will attempt to compile the binary using node-gyp (which may need to be installed).

On Ubuntu/Debian Linux distributions, if node-gyp throws errors during installation, the make and g++ prerequisites for compilation may need to first be installed with sudo apt install make and sudo apt install build-essential respectively.

Acknowledgements

barnowl-noble is based on the @stoprocent/noble open source Node.js package whose maintainer we invite you to consider supporting at buymeacoffee.com/stoprocent.

Contributing

Discover how to contribute to this open source project which upholds a standard code of conduct.

Security

Consult our security policy for best practices using this open source software and to report vulnerabilities.

License

MIT License

Copyright (c) 2025 reelyActive

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.