Lazy Attributes

[caiothomas]

Hello, I'm having doubts about the functionality of lazy attributes.
When I register a device the lazy attribute is not record in Orion. When doing a query in Orion this should make a request in the IoT Agent that will return the value of the attribute that was filled, is it correct?
In another test I registered the device entity before Orion. Whenever I perform an update on the lazy attribute, the Iot Agent updates in Orion, is it correct?

Best Regards,
Caio Thomas Oliveira

[dmoranj]

Hi Caio,

I don't know if I understand you correctly. Do you mean that if you create the entity in Orion before registering the device updating the device in Orion does not trigger the update in the IoTA?

You should be aware that Lazy attributes and Commands are not registered as NGSI attributes in Orion, but they are declared as provided by a Context Provider instead. This means that a query to the attribute will be redirected to the IoTA to get the answer instead of reading it from Orion's database.

If you clarify your scenario I will try to give you further help.

[caiothomas]

Hello Daniel,
From what I understand about the scenario, Orion must make a QueryContext request on the IoT Agent. However, when I make the QueryContext request in IoTAgent, it does not work correctly. I think the problem might be on the IoT Agent.

In another test I registered the device entity before Orion. Whenever I perform an update on the lazy attribute, the Iot Agent updates in Orion, is it correct?

I believe that it is correct to update the IoT Agent in Orion, since I previously registered an entity and it remained as an active attribute (not lazy).

Thanks.

[caiothomas]

I ran tests on iotagent-node-lib and queryContext is working. In iotagent-ul has a bug, I'll check where it is.

[caiothomas]

Hello,
By analyzing the IoT Agent code (iot-agent-node-lib), I noticed that it does not store lazy attribute data. Is the device that should implement it? Or when the device does an update it is identified lazy attribute and will be stored in the context in the IoT Agent?

Thanks.

[perrolobo]

By definition "lazy attributtes" resides always at device side. Lazy attributtes are the one that won't be propagated automatically to the IoTAgent but the device itself will provide once it is requested (vía queryContext to the IoTAgent).

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On Thu, Jan 19, 2017 at 3:24 PM, caiothomas ***@***.***> wrote: Hello, By analyzing the IoT Agent code (iot-agent-node-lib), I noticed that it does not store lazy attribute data. Is the device that should implement it? Or when the device does an update it is identified lazy attribute and will be stored in the context in the IoT Agent? Thanks. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#193 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA27Ujwl6uZzFD87FkD06l6-Olb2mXSGks5rT3IAgaJpZM4LZ8IT> .

-- - Marcos -

[caiothomas]

Okay, I got the concept. However, I do not understand if the device always publishes on the IoT Agent and it doesn't send updates to Orion. Or is there any other feature of MQTT?

Thanks.

[fgalan]

Lazy attribute support is parte of existing issue #23 . I understand that the present one can be closed.