HTTP dump of Libre Link Up used in combination with FreeStyle Libre 3

libre-link-up-http-dump.md

LibreLinkUp HTTP-Dump

This document describes the HTTP communication of LibreLinkUp which functions as follower app to receive cgm data. Some data in the responses were masked.

Context

This dump was created on an android device with LibreLinkUp app. Capturing was done with HttpToolkit over adb.

API Url

The global api url is https://api.libreview.io. If you are placed in europe you can use https://api-eu.libreview.io instead.

Headers

The following list includes general purpose headers but also specific ones which are required to get correct responses:

General purpose

'accept-encoding': 'gzip'
'cache-control': 'no-cache'
'connection': 'Keep-Alive'
'content-type': 'application/json'

Specific

The following headers are required and needs to be setted to get correct responses. There might be alternative values which are not known.

'product': 'llu.android'
'version': '4.2.1',

Request Flow

To get cgm data from the api it is required to fire at least three requests:

1. Login and retrieve JWT Token
2. Get connections of patients to get patientId
3. Retrieve cgm data of specific patient

Login

This request expects credentials and will return a JWT Token which is required to call auth-needed endpoints.

Endpoint POST /llu/auth/login

Request Body

{
  "email": "your-libre-email@provider.com",
  "password": "$yOurVerySecretPasSw0rd!"
}

Response

{
  "status": 0,
  "data": {
    "user": {
      "id": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
      "firstName": "John",
      "lastName": "Doe",
      "email": "your-libre-email@provider.com",
      "country": "DE",
      "uiLanguage": "de-DE",
      "communicationLanguage": "de-DE",
      "accountType": "pat",
      "uom": "1",
      "dateFormat": "2",
      "timeFormat": "2",
      "emailDay": [
        1
      ],
      "system": {
        "messages": {
          "firstUsePhoenix": 1652399492,
          "firstUsePhoenixReportsDataMerged": 1652399492,
          "lluGettingStartedBanner": 1652399555,
          "lluNewFeatureModal": 1652399526,
          "lluOnboarding": 1652399536,
          "lvWebPostRelease": "3.9.47"
        }
      },
      "details": {},
      "created": 1652399492,
      "lastLogin": 1653140180,
      "programs": {},
      "dateOfBirth": 627609600,
      "practices": {},
      "devices": {},
      "consents": {
        "llu": {
          "policyAccept": 1652399485,
          "touAccept": 1652399485
        }
      }
    },
    "messages": {
      "unread": 0
    },
    "notifications": {
      "unresolved": 0
    },
    "authTicket": {
      "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6IjZlZGFjNDk2LWQyNGUtMTFlYy04ZTVkLTAyNDJhYzExMDAwMiIsImZpcnN0TmFtZSI6IkhhbGltZSBTZWxjdWsiLCJsYXN0TmFtZSI6Iktla2VjIiwiY291bnRyeSI6IkRFIiwicmVnaW9uIjoiZXUiLCJyb2xlIjoicGF0aWVudCIsInVuaXRzIjoxLCJwcmFjdGljZXMiOltdLCJjIjoxLCJzIjoibGx1LmFuZHJvaWQiLCJleHAiOjE2Njg2OTIzNTh9.MdEzdJ3NrpYS4WVAcuy87Gxzk7EJFHzCtei-y7_XXXX",
      "expires": 1668692358,
      "duration": 15552000000
    },
    "invitations": [
      "xxxxxxxxx"
    ]
  }
}

The JWT Token is present in data.authTicket.token and is valid for nearly 6 month which is quite long. This is extremly long and actually you cannot invalidate this token why you should not share it with anyone.

For the next requests you have to set this token in the headers:

'authorization': Bearer [YOUR_JWT_TOKEN]

Get connections

To be able to retrieve cgm data you have to determine the patientId of the person who is sharing his data with you.

Endpoint GET /llu/connections

Response

{
  "status": 0,
  "data": [
    {
      "id": "xxxxx",
      "patientId": "xxxxxxx",
      "country": "DE",
      "status": 2,
      "firstName": "John",
      "lastName": "Doe",
      "targetLow": 70,
      "targetHigh": 130,
      "uom": 1,
      "sensor": {
        "deviceId": "",
        "sn": "xxxxx",
        "a": 1652400270,
        "w": 60,
        "pt": 4
      },
      "alarmRules": {
        "c": true,
        "h": {
          "on": true,
          "th": 130,
          "thmm": 7.2,
          "d": 1440,
          "f": 0.1
        },
        "f": {
          "th": 55,
          "thmm": 3,
          "d": 30,
          "tl": 10,
          "tlmm": 0.6
        },
        "l": {
          "on": true,
          "th": 70,
          "thmm": 3.9,
          "d": 1440,
          "tl": 10,
          "tlmm": 0.6
        },
        "nd": {
          "i": 20,
          "r": 5,
          "l": 6
        },
        "p": 5,
        "r": 5,
        "std": {}
      },
      "glucoseMeasurement": {
        "FactoryTimestamp": "5/21/2022 1:38:50 PM",
        "Timestamp": "5/21/2022 3:38:50 PM",
        "type": 1,
        "ValueInMgPerDl": 91,
        "TrendArrow": 3,
        "TrendMessage": null,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 91,
        "isHigh": false,
        "isLow": false
      },
      "glucoseItem": {
        "FactoryTimestamp": "5/21/2022 1:38:50 PM",
        "Timestamp": "5/21/2022 3:38:50 PM",
        "type": 1,
        "ValueInMgPerDl": 91,
        "TrendArrow": 3,
        "TrendMessage": null,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 91,
        "isHigh": false,
        "isLow": false
      },
      "glucoseAlarm": null,
      "patientDevice": {
        "did": "2d97357e-d250-11ec-b409-0242ac110004",
        "dtid": 40068,
        "v": "3.3.1",
        "ll": 65,
        "hl": 130,
        "u": 1653016896,
        "fixedLowAlarmValues": {
          "mgdl": 60,
          "mmoll": 3.3
        },
        "alarms": false
      },
      "created": 1652399545
    }
  ],
  "ticket": {
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6IjZlZGFjNDk2LWQyNGUtMTFlYy04ZTVkLTAyNDJhYzExMDAwMiIsImZpcnN0TmFtZSI6IkhhbGltZSBTZWxjdWsiLCJsYXN0TmFtZSI6Iktla2VjIiwiY291bnRyeSI6IkRFIiwicmVnaW9uIjoiZXUiLCJyb2xlIjoicGF0aWVudCIsInVuaXRzIjoxLCJwcmFjdGljZXMiOltdLCJjIjoxLCJzIjoibGx1LmFuZHJvaWQiLCJleHAiOjE2Njg2OTIzNTh9.MdEzdJ3NrpYS4WVAcuy87Gxzk7EJFHzCtei-y7_XXXX",
    "expires": 1668692358,
    "duration": 15552000000
  }
}

The datapart includes all persons who are sharing their data with you. To retrieve cgm data you need data[0].patientId.

Get cgm data

Now both prerequirements (JWT Token and Patient ID) are met and you can retrieve the cgm data.

Endpoint GET /llu/connections/{patientId}/graph

Response

{
  "status": 0,
  "data": {
    "connection": {
      "id": "xxxxxxx",
      "patientId": "xxxxxxx",
      "country": "DE",
      "status": 2,
      "firstName": "John",
      "lastName": "Doe",
      "targetLow": 70,
      "targetHigh": 130,
      "uom": 1,
      "sensor": {
        "deviceId": "",
        "sn": "XXXXXXXXXX",
        "a": 1652400270,
        "w": 60,
        "pt": 4
      },
      "alarmRules": {
        "c": true,
        "h": {
          "on": true,
          "th": 130,
          "thmm": 7.2,
          "d": 1440,
          "f": 0.1
        },
        "f": {
          "th": 55,
          "thmm": 3,
          "d": 30,
          "tl": 10,
          "tlmm": 0.6
        },
        "l": {
          "on": true,
          "th": 70,
          "thmm": 3.9,
          "d": 1440,
          "tl": 10,
          "tlmm": 0.6
        },
        "nd": {
          "i": 20,
          "r": 5,
          "l": 6
        },
        "p": 5,
        "r": 5,
        "std": {}
      },
      "glucoseMeasurement": {
        "FactoryTimestamp": "5/21/2022 1:38:50 PM",
        "Timestamp": "5/21/2022 3:38:50 PM",
        "type": 1,
        "ValueInMgPerDl": 91,
        "TrendArrow": 3,
        "TrendMessage": null,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 91,
        "isHigh": false,
        "isLow": false
      },
      "glucoseItem": {
        "FactoryTimestamp": "5/21/2022 1:38:50 PM",
        "Timestamp": "5/21/2022 3:38:50 PM",
        "type": 1,
        "ValueInMgPerDl": 91,
        "TrendArrow": 3,
        "TrendMessage": null,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 91,
        "isHigh": false,
        "isLow": false
      },
      "glucoseAlarm": null,
      "patientDevice": {
        "did": "xxxxxxx",
        "dtid": 40068,
        "v": "3.3.1",
        "ll": 65,
        "hl": 130,
        "u": 1653016896,
        "fixedLowAlarmValues": {
          "mgdl": 60,
          "mmoll": 3.3
        },
        "alarms": false
      },
      "created": 1652399545
    },
    "activeSensors": [
      {
        "sensor": {
          "deviceId": "xxxxxx",
          "sn": "xxxxx",
          "a": 1652400270,
          "w": 60,
          "pt": 4
        },
        "device": {
          "did": "xxxxxx",
          "dtid": 40068,
          "v": "3.3.1",
          "ll": 65,
          "hl": 130,
          "u": 1653016896,
          "fixedLowAlarmValues": {
            "mgdl": 60,
            "mmoll": 3.3
          },
          "alarms": false
        }
      },
      {
        "sensor": {
          "deviceId": "xxxxx",
          "sn": "xxxxxx",
          "a": 1652399154,
          "w": 60,
          "pt": 4
        },
        "device": {
          "did": "xxxxxxxxx",
          "dtid": 40068,
          "v": "3.3.1",
          "ll": 70,
          "hl": 250,
          "u": 1652399060,
          "fixedLowAlarmValues": {
            "mgdl": 60,
            "mmoll": 3.3
          },
          "alarms": false
        }
      },
      {
        "sensor": {
          "deviceId": "xxxxx",
          "sn": "xxxxx",
          "a": 1652391830,
          "w": 60,
          "pt": 4
        },
        "device": {
          "did": "xxxxx",
          "dtid": 40068,
          "v": "3.3.1",
          "ll": 70,
          "hl": 250,
          "u": 1652396851,
          "fixedLowAlarmValues": {
            "mgdl": 60,
            "mmoll": 3.3
          },
          "alarms": false
        }
      }
    ],
    "graphData": [
      {
        "FactoryTimestamp": "5/21/2022 1:39:50 AM",
        "Timestamp": "5/21/2022 3:39:50 AM",
        "type": 0,
        "ValueInMgPerDl": 117,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 117,
        "isHigh": false,
        "isLow": false
      },
      {
        "FactoryTimestamp": "5/21/2022 1:44:51 AM",
        "Timestamp": "5/21/2022 3:44:51 AM",
        "type": 0,
        "ValueInMgPerDl": 115,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 115,
        "isHigh": false,
        "isLow": false
      },
      {
        "FactoryTimestamp": "5/21/2022 1:49:50 AM",
        "Timestamp": "5/21/2022 3:49:50 AM",
        "type": 0,
        "ValueInMgPerDl": 115,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 115,
        "isHigh": false,
        "isLow": false
      },
      {
        "FactoryTimestamp": "5/21/2022 1:54:51 AM",
        "Timestamp": "5/21/2022 3:54:51 AM",
        "type": 0,
        "ValueInMgPerDl": 116,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 116,
        "isHigh": false,
        "isLow": false
      },
      {
        "FactoryTimestamp": "5/21/2022 1:59:50 AM",
        "Timestamp": "5/21/2022 3:59:50 AM",
        "type": 0,
        "ValueInMgPerDl": 116,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 116,
        "isHigh": false,
        "isLow": false
      },
      {
        "FactoryTimestamp": "5/21/2022 2:04:50 AM",
        "Timestamp": "5/21/2022 4:04:50 AM",
        "type": 0,
        "ValueInMgPerDl": 118,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 118,
        "isHigh": false,
        "isLow": false
      },
      {
        "FactoryTimestamp": "5/21/2022 2:09:50 AM",
        "Timestamp": "5/21/2022 4:09:50 AM",
        "type": 0,
        "ValueInMgPerDl": 118,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 118,
        "isHigh": false,
        "isLow": false
      },
      {
        "FactoryTimestamp": "5/21/2022 2:14:51 AM",
        "Timestamp": "5/21/2022 4:14:51 AM",
        "type": 0,
        "ValueInMgPerDl": 115,
        "MeasurementColor": 1,
        "GlucoseUnits": 1,
        "Value": 115,
        "isHigh": false,
        "isLow": false
      }
    ]
  },
  "ticket": {
    "token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6IjZlZGFjNDk2LWQyNGUtMTFlYy04ZTVkLTAyNDJhYzExMDAwMiIsImZpcnN0TmFtZSI6IkhhbGltZSBTZWxjdWsiLCJsYXN0TmFtZSI6Iktla2VjIiwiY291bnRyeSI6IkRFIiwicmVnaW9uIjoiZXUiLCJyb2xlIjoicGF0aWVudCIsInVuaXRzIjoxLCJwcmFjdGljZXMiOltdLCJjIjoxLCJzIjoibGx1LmFuZHJvaWQiLCJleHAiOjE2Njg2OTIzNTl9.LK8Ejr2IDKGM7oiObVYMHC8HV2bPcv6obt7UiEFXXXX",
    "expires": 1668692359,
    "duration": 15552000000
  }
}

The last measurement is present in glucoseMeasurement:

{
  "FactoryTimestamp": "5/21/2022 1:38:50 PM",
  "Timestamp": "5/21/2022 3:38:50 PM",
  "type": 1,
  "ValueInMgPerDl": 91,
  "TrendArrow": 3,
  "TrendMessage": null,
  "MeasurementColor": 1,
  "GlucoseUnits": 1,
  "Value": 91,
  "isHigh": false,
  "isLow": false
}

Instead you can find historical measurements in graphData. The data has the same shape as above.

Contact

Selcuk Kekec

E-mail: khskekec@gmail.com

@Mynuggets-dev Great that you exposed your scripting with others with your website! It looks good. Nice example for other developers. I hope one day I will provide machine-learned alerting service to others. At the moment I am too busy with other things. Keep going!

I’ve shared a simplified client API example I’ve been using.
On my side I run a more complete setup with additional layers for reliability, including an admin panel and data storage for analytics (I log readings roughly every minute for visualisation purposes).
I also have the ability to adjust ranges/alerts within my own tooling for testing and experimentation.
This is purely a personal project and not intended for medical use or as a clinical decision tool. Anyone building on this should implement their own safeguards and validation.