Posting historical data into Orion Contex Broker with a different date

Question

We have found an issue that is important for us and we need to solve before proceeding with Orion Contex Broker. In our distributed network we cannot assume links are allways up and sometimes we have historic values probed in past time that we want to push to contex broker as soon as communications are recovered. These probes should be delivered to Orion with measure time attached and then sent to Hadoop via Cygnus.

After having a look to Orion API it seems posted values are assumed to be current and there is no way to tell that they are values probed half an hour ago (for instance).

Our doubts:

1) Could it be some way to tell Context Broker the time of de information being pushed?

2) If not, perhaps this situation should be solved by other means? Is there already some component or IoT Ge that placed besides probes queues probes until links are recovered and then push them to central Context Broker with correct timestamp?

Thanks

frb frb · Accepted Answer · 2015-04-29T19:58:32

I think you can attach metadata to your attribute about the timestamp the data was supposed to be created. This kind of metadata is stored as well by Cygnus into HDFS, as shown in this example:

{
    "recvTimeTs":"13453464536",
    "recvTime":"2014-02-27T14:46:21Z",
    "entityId":"Room1",
    "entityType":"Room",
    "attrName":"temperature",
    "attrType":"centigrade",
    "attrValue":"26.5",
    "attrMd":[
        {
            name:CreationTime,
            type:timestamp,
            value:2014-02-26T12:34:09.672Z
        }
    ]
}

In this case you have the reception time (recvTime) and the creation time (the metadata).

Posting historical data into Orion Contex Broker with a different date

1 Answers