node-beacon-scanner

node-beacon-scanner

The node-beacon-scanner is a Node.js module which allows you to scan BLE beacon packets and parse the packet data. This module supports iBeacon, Eddystone, and Estimote.

The supported beacon data formats are as follows:

• iBeacon
• Eddystone-UID
• Eddystone-URL
• Eddystone-TLM (Unencrypted)
• Eddystone-EID
• Estimote-Telemetry
• Estimote-Nearable

Dependencies

• Node.js 6 +
• @abandonware/noble

See the document of the @abandonware/noble for details on installing the @abandonware/noble.

Note that the noble has to be run as root on most of Linux environments. See the the document of the @abandonware/noble for details.

The early versions of this module depended on noble for BLE handling. But the noble seems not to support Node v10 or later versions. Now, this module is employing @abandonware/noble, which was forked from noble. For the purouse of the backward compatibility, this module works with noble on Node v8 or earlier versions.

Installation

$ cd ~
$ npm install @abandonware/noble
$ npm install node-beacon-scanner

---

Table of Contents

• Quick Start
• BeaconScanner object
  • scartScan() method
  • stopScan() method
  • onadvertisement event handler
• BeaconScannerAdvertisement object
• Release Note
• References
• License

---

Quick Start

This sample code shows how to start scanning and how to get parsed packets.

const BeaconScanner = require('node-beacon-scanner');
const scanner = new BeaconScanner();

// Set an Event handler for becons
scanner.onadvertisement = (ad) => {
  console.log(JSON.stringify(ad, null, '  '));
};

// Start scanning
scanner.startScan().then(() => {
  console.log('Started to scan.')  ;
}).catch((error) => {
  console.error(error);
});

The sample code above will output the result as follows:

Started to scan.
{
  "id": "c7dfbfd9f64a",
  "address": "c7:df:bf:d9:f6:4a",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "iBeacon",
  "iBeacon": {
    "uuid": "B9407F30-F5F8-466E-AFF9-25556B57FE6D",
    "major": 21983,
    "minor": 57807,
    "txPower": 180
  }
}
...

---

BeaconScanner object

In order to use the node-beacon-scanner, you have to load the node-beacon-scanner module as follows:

const BeaconScanner = require('node-beacon-scanner');

You can get an BeaconScanner constructor from the code above. Then you have to create an BeaconScanner object from the BeaconScanner constructor as follows:

const scanner = new BeaconScanner();

The BeaconScanner constructor takes an argument optionally. It must be a hash object containing the properties as follows:

Property	Type	Required	Description
noble	Noble	option	a Noble object of the noble module

The node-beacon-scanner module uses the noble module in order to scan the beacons coming from the BLE beacon device(s). If you want to interact other BLE devices using the noble module, you can create an Noble object by yourself, then pass it to this module. If you don't specify a Noble object to the noble property, this module automatically create a Noble object internally.

The sample code below shows how to pass a Nobel object to the Linking constructor.

// Create a Noble object
const noble = require('noble');

// Create a Linking object
const BeaconScanner = require('node-beacon-scanner');
const scanner = new BeaconScanner({'noble': noble});

In the code snippet above, the variable scanner is a BeaconScanner object. The BeaconScanner object has methods as described in sections below.

scartScan() method

The startScan() method starts to scan advertising packets from BLE beacon devices. This method returns a Promise object.

Whenever a packet is received, the callback function set to the onadvertisement property of the BeaconScanner object will be called. When a packet is received, an BeaconScannerAdvertisement object will be passed to the callback function.

// Set an Event handler for becons
scanner.onadvertisement = (ad) => {
  console.log(JSON.stringify(ad, null, '  '));
};

// Start scanning
scanner.startScan().then(() => {
  console.log('Started to scan.')  ;
}).catch((error) => {
  console.error(error);
});

stopScan() method

The stopScan() method stops to scan advertising packets from BLE beacon devices. See the section "startScan() method" for details.

onadvertisement event handler

If a callback function is set to the onadvertisement property, the callback function will be called whenever an advertising packet is received from a BLE beacon device during the scan is active (from the moment when the startScan() method is called, to the moment when the stopScan() method is called).

See the section "startScan() method" for details.

---

BeaconScannerAdvertisement object

The BeaconScannerAdvertisement object represents an advertising data coming from the BLE beacon device. This object is just a hash object containing properties as follows. Note that the structure varies depending on the format of the beacon. You can know the format of the beacon from the value of the beaconType property.

iBeacon

{
  "id": "c7dfbfd9f64a",
  "address": "c7:df:bf:d9:f6:4a",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "iBeacon",
  "iBeacon": {
    "uuid": "B9407F30-F5F8-466E-AFF9-25556B57FE6D",
    "major": 21983,
    "minor": 57807,
    "txPower": 180
  }
}

The value of the iBeacon property contains the properties as follows:

Property	Type	Description
uuid	String	Proximity UUID
major	Number	Major
minor	Number	Minor
txPower	Number	Measured Power (dBm)

Eddystone-UID

{
  "id": "c6debed8f549",
  "address": "c6:de:be:d8:f5:49",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "eddystoneUid",
  "eddystoneUid": {
    "txPower": -35,
    "namespace": "EDD1EBEAC04E5DEFA017",
    "instance": "2D3EA3203B6B"
  }
}

The value of the eddystoneUid property contains the properties as follows:

Property	Type	Description
namespace	String	Namespace ID
instance	String	Instance ID
txPower	Number	Calibrated Tx power (dBm)

Eddystone-URL

{
  "id": "c6debed8f549",
  "address": "c6:de:be:d8:f5:49",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "eddystoneUrl",
  "eddystoneUrl": {
    "txPower": -35,
    "url": "http://go.esti.be/"
  }
}

The value of the eddystoneUrl property contains the properties as follows:

Property	Type	Description
url	String	Decoded URL
txPower	Number	Calibrated Tx power (dBm)

Eddystone-TLM (Unencrypted)

{
  "id": "c6debed8f549",
  "address": "c6:de:be:d8:f5:49",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "eddystoneTlm",
  "eddystoneTlm": {
    "batteryVoltage": 6059,
    "temperature": 28.59765625,
    "advCnt": 83,
    "secCnt": 361299
  }
}

The value of the eddystoneTlm property contains the properties as follows:

Property	Type	Description
batteryVoltage	Number	Battery voltage (mV)
temperature	Number	Beacon temperature (°C)
advCnt	Number	Advertising PDU count
secCnt	Number	Time since power-on or reboot

Eddystone-EID

{
  "id": "d9d9fe86fb61",
  "address": "d9:d9:fe:86:fb:61",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "eddystoneEid",
  "eddystoneEid": {
    "txPower": -35,
    "eid": "79c58b83f198ddbe"
  }
}

The value of the eddystoneEid property contains the properties as follows:

Property	Type	Description
eid	String	Ephemeral Identifier
txPower	Number	Calibrated Tx power (dBm)

Estimote-Telemetry

There are two types in the Estimote Telemetry beacon data: Type A and Type B. The types can be obtained checking the value of the subFrameType property. If the type is A, the value is 0. If the type is B, the value is 1.

Type A

{
  "id": "c9e1c1dbf84c",
  "address": "c9:e1:c1:db:f8:4c",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "estimoteTelemetry",
  "estimoteTelemetry": {
    "frameType": 2,
    "subFrameType": 0,
    "protocolVersion": 2,
    "shortIdentifier": "2d3ea3203b6b2446",
    "acceleration": {
      "x": -0.015748031496062992,
      "y": -0.07874015748031496,
      "z": 0.9921259842519685
    },
    "moving": false,
    "gpio": {
      "pin0": "low",
      "pin1": "low",
      "pin2": "high",
      "pin3": "high"
    },
    "errors": {
      "firmware": false,
      "clock": false
    },
    "pressure": 100304.9765625
  }
}

Type B

{
  "id": "c9e1c1dbf84c",
  "address": "c9:e1:c1:db:f8:4c",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "estimoteTelemetry",
  "estimoteTelemetry": {
    "frameType": 2,
    "subFrameType": 1,
    "protocolVersion": 2,
    "shortIdentifier": "2d3ea3203b6b2446",
    "magneticField": {
      "x": 0,
      "y": 0,
      "z": 0
    },
    "light": 80.64,
    "uptime": {
      "unitCode": 1,
      "unitDesc": "minutes",
      "value": 596
    },
    "temperature": 28.75,
    "batteryVoltage": 6059,
    "batteryLevel": 95
  }
}

Estimote-Nearable

{
  "id": "f8d3c05e8001",
  "address": "f8:d3:c0:5e:80:01",
  "localName": null,
  "txPowerLevel": null,
  "rssi": -59,
  "beaconType": "estimoteNearable",
  "estimoteNearable": {
    "nearableId": "bd20de5cd074de8d",
    "temperature": 25.75,
    "moving": false,
    "acceleration": {
      "x": -15.625,
      "y": -78.125,
      "z": -1031.25
    }
  }
}

The value of the estimoteNearable property contains the properties as follows:

Property		Type	Description
nearableId		String	Nearable identifier
temperature		Number	Temperature (°C)
moving		Boolean	Moving state (true: moving)
acceleration		Object	Acceleration
--	x	Number	Acceleration on the X axis (milli G)
--	y	Number	Acceleration on the Y axis (milli G)
--	z	Number	Acceleration on the Z axis (milli G)

---

Release Note

• v0.2.2 (2019-11-24)
  • Fixed a bug that the txPower of iBeacon was wrong. (Thanks to @girtgirt)
  • Fixed a bug that an exception was thrown whenever it received an advertisement packet without service data. (Thanks to @charlesread)
• v0.2.1 (2019-11-02)
  • Fixed a typo of a property name in the BeaconScannerAdvertisement object for Eddystone (namespece -> namespace). (Thanks to @natcl)
• v0.2.0 (2019-10-25)
  • Supported Node v10 or later versions thanks to @abandonware/noble
• v0.1.1 (2018-12-27)
  • Fixed the bug that Eddystone beacons were not discovered if iBeacons were present as well. (Thanks to @Tiggu)
• v0.1.0 (2018-07-14)
  • Supported the Eddystone-UID of Kontakt. The spec of the Eddystone-UID defines that the packet size is 20 bytes (the last 2 bytes are RFU). But the size of the packet form Kontakt device is 18 bytes. (Thanks to @EwaRvr)
• v0.0.3 (2018-06-24)
  • Fixed a bug that an exception was thrown when an unknown packet came.
• v0.0.2 (2017-09-15)
  • Fixed a bug that an exception was thrown when an unknown packet came.
• v0.0.1 (2017-09-06)
  • First public release

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References

• Eddystone Protocol Specification
  • Eddystone-UID
  • Eddystone-URL
  • Eddystone-TLM
  • Eddystone-EID
• iBeacon - Apple Developer
• Estimote packet specs

---

License

The MIT License (MIT)

Copyright (c) 2017-2019 Futomi Hatano

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.