Created question in FIWARE Q/A platform on 28-12-2015 at 11:12
Please, ANSWER this question AT https://stackoverflow.com/questions/34491828/fiware-orion-context-broker-metadata-updates-trigger-notifications

Question:
FIWARE-Orion Context Broker metadata updates trigger notifications

Description:
I'm using 3 FIWARE GEs: IDAS+Orion+CEP.
As reported in the Orion documentation (https://github.com/telefonicaid/fiware-orion/blob/develop/doc/manuals/user/metadata.md) "changing the metadata of a given attribute or adding a new metadata element is considered a change even if attribute value itself hasn't changed".
Is there a way to send notifications from Orion only if the value of the attribute specified in the subscription changes?

I've tried the solution proposed in the documentation, delete and re-create the attribute, in order to remove the metadata. But, since the messages to Orion are produced by IDAS, the metadata are created with the new communication.

Thanks.

UPDATE:

GEs Version:

• Orion - 0.26.1-next
• IoTAgent (IDAS) - 1.3.1

The metadata added by IDAS are:

"attributes" : [
{
"name" : "temperature",
"type" : "int",
"value" : "37",
"metadatas" : [

]
}
]

Specifically, from mongodb query:

"temperature" : { "value" : "37", "type" : "int", "md" : [

], "creDate" : 1450716887, "modDate" : 1451393164 }