FIWARE Orion: Filter subscriptions

Question

We use Orion to register subscriptions. There are two kinds of subscriptions in our application:

user subscriptions: they are created by the user using our GUI.
internal subscriptions: they are used by the system for communication between the components.

The problem is to distinguish the two, in order to present the user with only user-oriented subscriptions. Which field of the subscriptions can I use? It would be nice to have a field "type", for instance.

Emiliano Viotti Emiliano Viotti · Accepted Answer · 2018-02-09T15:51:01

I agree with what Jose Manuel says, it would be a really nice feature.

In addition to his reply, in the meantime I think you can use "metadata" field in subscriptions for distinguish between user subscriptions and internal subscriptions. Just have in mind that this field is not supposed for this purposes and its kind a "dark" way to implement the behavior that you want.

Here is an example of a subscription creation with my approach. In this case you create a subscription with the metadata field "isInternal" that just tells you that this is an internal subscription. Then you can use another different metadata field as a token, just to identify a user subscription:

curl -X POST \
  http://localhost:1026/v2/subscriptions \
  -H 'Content-Type: application/json' \
  -d '{
       "description": "A subscription to get info about Room1",
       "subject": {
         "entities": [
           {
             "id": "Room1",
             "type": "Room"
           }
         ],
         "condition": {
           "attrs": [
             "temperature"
           ]
         }
       },
       "notification": {
         "http": {
           "url": "http://localhost:1028/accumulate"
         },
         "attrs": ["temperature"],
         "metadata": ["isInternal"]
       }
     }'

For more information about metadata field in subscriptions and his normal use please refer to this documentation.

FIWARE Orion: Filter subscriptions

3 Answers