System: Bluetooth REST API Microservice

Prerequisites:

as Docker container, it needs to be run with next options to grant access:

 --net=host --privileged 

in other cases it needs to start under root user You can use the rootHostAccess field of the microservice yaml definition to grant root access to the host to your container

Description:

Upon startup the container will start scanning if bluetooth is powered on and upon discovering devices it will store them locally and generate an internal ID. In most cases the container will work with this locally stored devices unless the scanning is restarted. If container received command to restart scanning it will delete all previously stored devices and start scanning anew ( which results in generating new local IDs for devices). Container will return 'Timeout exception' in case if it didn't get any results of processing.

For example, if you try to hit http://localhost:10500/device/mac/{mac}/services?scan=true endpoint you can get 'Timeout exception' for next reasons:

1. device with specified mac was't found while scanning anew

2. device is inactive and container hang up on trying to connect to it

3. after connecting to device container hang up on discovering services

Container provides next REST endpoints :

Set Device Identifier (POST)

This endpoint provides the possibility to set config for bluetooth-rest-api system container, upon receiving config container will wipe out all previously stored devices and restart scanning. 'name' - will tell container differentiate devices' uniqueness by localname, 'mac' - will tell container differentiate devices' uniqueness by mac address

Request

Endpoint 1
http://localhost:10500/config/scan
POST JSON raw body
{ "deviceIdentifier" : "name"/"mac" }

Response

"New config applied. Scanning restarted"

Turn ON/OFF level of logging (POST)

This endpoint provides the possibility to turn ON/OFF DEBUG level logging (empty level value will turn off/ "DEBUG" will show exessive logs)

Request

Endpoint 2
http://localhost:10500/config/logging
POST JSON raw body
{ "LOG_LEVEL" : "DEBUG" }

Response

"LOG_LEVEL = ${LOG_LEVEL} is applied"

Restart scanning

This endpoint sends the command to restart scanning to a container. As a result all previously stored devices will be wiped out and then the scanning will be restarted.

Request

Endpoint 3
http://localhost:10500/scan/restart

Response

"Scanning restarted"

Get list of devices (GET)

This endpoint returns a list of discovered devices till current moment.

Request

Endpoint 4
http://localhost:10500/devices

Response

[
  {
    "id": "TzPxHVbBnn",
    "mac-address": "fe:10:4f:c6:b9:39",
    "local-name": "Kontakt",
    "mac-id": "fe104fc6b939",
    "rssi": -74
  },
  {
    "id": "MvSG3gCXU3",
    "mac-address": "5b:d7:13:2b:f9:42",
    "mac-id": "5bd7132bf942",
    "rssi": -81
  }
]

Get list of services (GET)

This endpoint returns a list of services discovered for specified device ID/Mac Address.

Request

Endpoint 5
http://localhost:10500/device/iid/{ID}/services

Request

Endpoint 6
http://localhost:10500/device/mac/{mac}/services

Response

[
  {
    "uuid": "1800",
    "name": "Generic Access",
    "type": "org.bluetooth.service.generic_access"
  },
  {
    "uuid": "1801",
    "name": "Generic Attribute",
    "type": "org.bluetooth.service.generic_attribute"
  },
  {
    "uuid": "180a",
    "name": "Device Information",
    "type": "org.bluetooth.service.device_information"
  },
  {
    "uuid": "1804",
    "name": "Tx Power",
    "type": "org.bluetooth.service.tx_power"
  },
  {
    "uuid": "180f",
    "name": "Battery Service",
    "type": "org.bluetooth.service.battery_service"
  },
  {
    "uuid": "a1ea81100e1bd4a1b84063f88c8da1ea",
    "name": null,
    "type": null
  },
  {
    "uuid": "a1ea81200e1bd4a1b84063f88c8da1ea",
    "name": null,
    "type": null
  },
  {
    "uuid": "a1ea81300e1bd4a1b84063f88c8da1ea",
    "name": null,
    "type": null
  }
]

Get list of characteristics (GET)

This endpoint returns the list of discovered characteristics for specified service sID and device dID/Mac Address

Request

Endpoint 7
http://localhost:10500/device/iid/{dID}/service/{sID}/characteristics

Request

Endpoint 8
http://localhost:10500/device/mac/{mac}/service/{sID}/characteristics

Response

[
  {
    "uuid": "2a00",
    "name": "Device Name",
    "type": "org.bluetooth.characteristic.gap.device_name",
    "properties": ["read"]
  },
  {
    "uuid": "2a01",
    "name": "Appearance",
    "type": "org.bluetooth.characteristic.gap.appearance",
    "properties": ["read"]
  },
  {
    "uuid": "2a04",
    "name": "Peripheral Preferred Connection Parameters",
    "type": "org.bluetooth.characteristic.gap.peripheral_preferred_connection_parameters",
    "properties": ["read"]
  }
]

Read characteristic's value (GET)

This endpoint reads the value from specified characteristic cID for specified service sID and device dID/Mac Address

Request

Endpoint 9
http://localhost:10500/device/iid/{dID}/service/{sID}/characteristic/{cID}

Request

Endpoint 10
http://localhost:10500/device/mac/{mac}/service/{sID}/characteristic/{cID}

Response

{
  "data": "base64 encoded data"
}

Write value to characteristic (POST)

This endpoint writes value to specified characteristic cID for specified service sID and device dID/Mac Address

Request

Endpoint 11
http://localhost:10500/device/iid/{dID}/service/{sID}/characteristic/{cID}

Request

Endpoint 12
http://localhost:10500/device/mac/{mac}/service/{sID}/characteristic/{cID}
POST JSON raw body
"withresponse" isn't required (in case it's omitted the default value will be false)
{ "data" : "base64 encoded data" , "withresponse" : true }

Response

"Success writing data to characteristic id = cID"

Get list of descriptors (GET)

This endpoint returns a list of discovered descriptors for specified characteristic cID, service sID and device dID/Mac Address

Request

Endpoint 13
http://localhost:10500/device/id/{dID}/service/{sID}/characteristic/{cID}/descriptors

Request

Endpoint 14
http://localhost:10500/device/mac/{mac}/service/{sID}/characteristic/{cID}/descriptors

Response

[
  {
    "uuid": "2901",
    "name": "Characteristic User Description",
    "type": "org.bluetooth.descriptor.gatt.characteristic_user_description"
  },
  {
    "uuid": "2900",
    "name": "Characteristic Extended Properties",
    "type": "org.bluetooth.descriptor.gatt.characteristic_extended_properties"
  }
]

Read the value from descriptor (GET)

This endpoint reads the value from specified descriptor dsID for specified characteristic cID, service sID and device dID/Mac Address

Request

Endpoint 15
http://localhost:10500/device/iid/{dID}/service/{sID}/characteristic/{cID}/descriptor/{dsID}

Request

Endpoint 16
http://localhost:10500/device/mac/{mac}/service/{sID}/characteristic/{cID}/descriptor/{dsID}

Response

{
  "data": "base64 encoded data"
}

Subscribe to characteristic's notify event (GET)

This endpoint sets notify property to true for specified characteristic's cID for specified service sID and device dID/Mac Address and returns url where buffered values can be picked up. If timeout parameter is specified (in millisecond) it'll be applied, otherwise RESTBlue will use the default value 1 min (60000 milliseconds). This timeout is specified to handle usecase when device is still connected and advertising, but RESTBlue stopped receiving any data on notify subscription. When picking up buffered notify data:

• If RESTBlue doesn't receive any data for more than specified timeout it will unsubscribe and remove notify buffer url and return 500 status code with error:TIMEOUT_DATA.
• In case if device disconnected while being subscribed the response will be OK with device_disconnected:true and last batch of data.

Request

Endpoint 17
http://localhost:10500/device/iid/{dID}/service/{sID}/characteristic/{cID}/notify??timeout=TIME_MILLISEC

Request

Endpoint 18
http://localhost:10500/device/mac/{mac}/service/{sID}/characteristic/{cID}/notify

Response

{
  "message": "Notification is turned ON for characteristic uuid = CH_ID ",
  "url": "notify_buffer/BUFFER_GENERATEDID"
}

Check status of Bluetooth Adapter (GET)

This endpoint return the status of Bluetooth Adapter: if it'spowered on/off (true/false).

Request

Endpoint 19
http://localhost:10500/status

Response

{
  "bluetooth_adapter_powered_on": true / false
}

Parameters for endpoint 5-18:

• scan=true : This parameter will tell REST Blue to stop scanning, clean up previously stored devices and start scan again and look for specified in the url device.
• drct=1000 : Device reconnect timeout. Default value = 1000 millisecond. This parameter is specified in milliseconds, it's a timeout that REST Blue will wait to reconnect to device after receiving disconnect event for this device. REST Blue will try to reconnect only if it was subscribed on device's notifications and is storing data for 'NOTIFY Buffer' functionality.
• drca=5 : Device reconnect attempts. Default value = 5 attempts. This parameter specifies how many attempts REST Blue should make to reconnect to device in case it lost connection while being subscribed to data notifications.

For Endpoints number 5-18 all the operations will be performed with previously scanned devices (the scanning starts upon container's start). For Endpoints numbers 6, 8, 10, 12, 14, 16, 18 (basically the ones with mac parameter to identify device) if add scan=true parameter to url, new device can be searched.

Launching the Container

The REST Blue images will always be available on ioFog Controllers using the catalog item ID 2.

Please refer to the catalog overview if you don't know yet how to deploy microservices using catalog items.