Node Web Bluetooth

Node.js implementation of the Web Bluetooth Specification

Prerequisites

Node.js > v10.20.0, which includes npm.

Installation

$ npm install webbluetooth

Getting Started

See the examples or view the API documentation at:

https://thegecko.github.io/webbluetooth/

Usage

The module exports a default navigator.bluetooth instance, the Bluetooth class to allow you to instantiate your own bluetooth instances and the Bluetooth helper methods:

• bluetooth
• Bluetooth()
• BluetoothUUID.getService()
• BluetoothUUID.getCharacteristic()
• BluetoothUUID.getDescriptor()
• BluetoothUUID.canonicalUUID()

Using the default bluetooth instance

To use existing Web Bluetooth scripts, you can simply use the default bluetooth instance in place of the navigator.bluetooth object:

const bluetooth = require('webbluetooth').bluetooth;

const device = await bluetooth.requestDevice({
    filters:[{ services:[ 'heart_rate' ] }]
});

const server = await device.gatt.connect();
...

The first device matching the filters will be returned.

Creating your own bluetooth instances

You may want to create your own instance of the Bluetooth class. For example, to inject a device chooser function or control the referring device:

const Bluetooth = require('webbluetooth').Bluetooth;

const deviceFound = (device, selectFn) => {
    // If device can be automatically selected, do so by returning true
    if (device.name === 'myName') return true;

    // Otherwise store the selectFn somewhere and execute it later to select this device
};

const bluetooth = new Bluetooth({ deviceFound });

const device = await bluetooth.requestDevice({
    filters:[{ services:[ 'heart_rate' ] }]
});

const server = await device.gatt.connect();
...

Specification

The Web Bluetooth specification can be found here:

https://webbluetoothcg.github.io/web-bluetooth/

Implementation Status

bluetooth

• [ ] getAvailability() - unsupported in adapter
• [x] referringDevice
• [x] requestDevice()
• [x] getDevices()
• [x] RequestDeviceOptions.filter.name
• [x] RequestDeviceOptions.filter.namePrefix
• [x] RequestDeviceOptions.filter.services
• [x] RequestDeviceOptions.filter.manufacturerData
• [x] RequestDeviceOptions.filter.serviceData
• [x] RequestDeviceOptions.acceptAllDevices
• [x] RequestDeviceOptions.optionalServices
• [ ] RequestDeviceOptions.exclusionFilters
• [ ] RequestDeviceOptions.optionalManufacturerData - used in advertisements, unsupported in adapter

BluetoothDevice

• [x] id
• [x] name
• [x] gatt
• [x] forget()
• [ ] watchAdvertisements() - unsupported in adapter
• [ ] watchingAdvertisements - unsupported in adapter

BluetoothRemoteGATTServer

• [x] device
• [x] connected
• [x] connect()
• [x] disconnect()
• [x] getPrimaryService()
• [x] getPrimaryServices()

BluetoothRemoteGATTService

• [x] uuid
• [x] device
• [x] isPrimary
• [x] getCharacteristic()
• [x] getCharacteristics()
• [ ] getIncludedService() - unsupported in adapter
• [ ] getIncludedServices() - unsupported in adapter

BluetoothRemoteGATTCharacteristic

• [x] uuid
• [x] service
• [x] value
• [ ] properties.broadcast - unsupported in adapter
• [x] properties.read
• [x] properties.writeWithoutResponse
• [x] properties.write
• [x] properties.notify
• [x] properties.indicate
• [ ] properties.authenticatedSignedWrites - unsupported in adapter
• [ ] properties.reliableWrite - unsupported in adapter
• [ ] properties.writableAuxiliaries - unsupported in adapter
• [x] getDescriptor()
• [x] getDescriptors()
• [x] readValue()
• [x] writeValue()
• [x] writeValueWithResponse()
• [x] writeValueWithoutResponse()
• [x] startNotifications()
• [x] stopNotifications()

BluetoothRemoteGATTDescriptor

• [x] uuid
• [x] characteristic
• [x] value
• [x] readValue()
• [x] writeValue()

BluetoothUUID

• [x] getService()
• [x] getCharacteristic()
• [x] getDescriptor()
• [x] canonicalUUID()

Events

Bluetooth

• [ ] availabilitychanged - unsupported in adapter

Bluetooth Device

• [x] gattserverdisconnected
• [ ] advertisementreceived - unsupported in adapter

Bluetooth Service

• [x] serviceadded
• [ ] servicechanged - unsupported in adapter
• [ ] serviceremoved - unsupported in adapter

Bluetooth Characteristic

• [x] characteristicvaluechanged

Other

• [x] Device selector hook
• [x] Examples
• [x] API Documentation

Development

Cloning

This repository uses a submodule to reference the SimpleBLE library. Clone it as follows:

git clone https://github.com/thegecko/webbluetooth
cd webbluetooth
git submodule update --init

Building

To build the SimpleBLE module, bindings and TypeScriptsource, run:

yarn build:all

Testing

The tests are set up to use a BBC micro:bit in range with the following services available:

• Device Info Service (0000180a-0000-1000-8000-00805f9b34fb)
• LED Service (e95dd91d-251d-470a-a062-fa1922dfa9a8)
• Button Service (e95d9882-251d-470a-a062-fa1922dfa9a8)

Firmware for this hardware including the services can be found here: https://microbit.org/get-started/user-guide/firmware/

To run the tests:

yarn test