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Orion CB output regarding provisioned device

I have noticed that upon querying Orion CB, while it is working with provisioned devices and having IoT Agent receive HTTP and MQTT messages, it will always output all the values written in the quotation marks:

{
    "id": "sensor_data",
    "type": "Sensor",
    "ActiveTime": {
        "type": "Seconds",
        "value": "17703",
        "metadata": {
            "TimeInstant": {
                "type": "ISO8601",
                "value": "2018-07-04T13:32:27.357Z"
            }
        }
    },
    "Distance": {
        "type": "Number",
        "value": "312",
        "metadata": {
            "TimeInstant": {
                "type": "ISO8601",
                "value": "2018-07-04T13:32:27.413Z"
            }
        }
    }
}

However, if to work with only entities in Orion CB, it is possible to receive actual values (like in the example in the manual):

{
"id": "Room1",
"pressure": {
    "metadata": {},
    "type": "Integer",
    "value": 720
},
"temperature": {
    "metadata": {},
    "type": "Float",
    "value": 23
},
"type": "Room"
}

Sometimes, I need to receive the actual value from my sensor in order to format it and use in further applications, but they are in quotation marks, which makes it a little difficult. Is it possible to somehow change?(maybe in device provisioning), or it really should be that way regarding devices? Thanks in advance!

EDIT 1 This is the way I provisioned the device:

{ 
"devices": [ 
    { 
        "device_id": "sensor_data", 
        "entity_name": "sensor_data", 
        "entity_type": "Sensor",
        "transport": "MQTT",
        "timezone": "Europe/Helsinki",
        "attributes": [ 
           { "object_id": "act", "name": "ActiveTime", "type": "Seconds"},
           { "object_id": "dst", "name": "Distance", "type": "Number"}
        ]
    }
]
}

And this is how the MQTT messages are sent from my sensor (I have set up the topics for IoT Agent to understand them)

/123456789/sensor_data/attrs/act 12 /123456789/sensor_data/attrs/dst 322

123456789 is the API Key I have set here.

Solution

  • This situation tipycally happens when IoT Agents uses NGSIv1 to push data to Context Broker, given that NGSIv1 always "string-fy" any attribute value. Recently, the ability to use NGSIv2 (which doesn't have this limitatino) was introduced in IoT Agents.

    In order to solve your problem you have to:

    • Use a recent IOTA-UL version (the current one from master branch will work)

    • Enable NGSIv2 in configuration as explained in documentation. This is done in the config.js file:

      config.iota = {
  ...    
     contextBroker: {
     ...
     ngsiVersion: 'v2'
  }
...
}

      or using environament variable IOTA_CB_NGSI_VERSION=v2 for the IOTA-UL process.

    • Enable autocast as explained in documentation. This is done in config.js file:

      config.iota = {
  ...    
  autocast: true,
  ...
}

      or using environament variable IOTA_AUTOCAST=true for the IOTA-UL process.

    • Set the right type for each attribute at provision time. The documentation here) provides the right types:

      • Type "Number" for integer or float numbers
      • Type "Boolean" for boolean
      • Type "None" for null

      Thus, in your case the provisioning for Distance is ok, but for ActiveTime you should use also Number as type.