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": "[email protected]",
  "password": "$yOurVerySecretPasSw0rd!"
}

Response

{
  "status": 0,
  "data": {
    "user": {
      "id": "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx",
      "firstName": "John",
      "lastName": "Doe",
      "email": "[email protected]",
      "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: [email protected]

Quirk of the day: today I got {"message":"invalid or expired jwt"} back from POST /llu/auth/login. My credentials were correct, but I needed to accept terms and conditions in the librelinkup app ¯_(ツ)_/¯

If you haven't stored all your responses then you can't verify what I am about to say, but I don't think the message was as a response from the `POST /llu/auth/login' , but the next stage.

It seems to be a common issue and most of the third party routines I've seen don't seem to handle the login process correctly, but assume that if you get an HttpStatus of OK when you can proceed as normal, but you are supposed to look at the status inside the response message and if this is 4, look to see if you need to perform an extra step.

So you should have gotten a response which looks something like

{
  "status": 4,
  "data": {
    "step": {
      "type": "pp",
      "componentName": "AcceptDocument",
      "props": {
        "reaccept": true,
        "titleKey": "Common.privacyPolicy",
        "type": "pp"
      }
    },

   ...

  }
}

If you get a status 4 and a step in your response, you are supposed to post a request to auth/continue/xxxx where xxxx is the type (so in this case the request would go to auth/continue/pp .

You might have several of these steps until you get a response with status 0 which means you can continue as normal.

Yeah, part of me is really annoyed at not capturing everything - but the other half is happy to have fixed my nightscout feed after a power outage.
As it says in an earlier comment, the authtoken is valid for 6 months, so my code almost never calls the earlier stages.