rajesh.palanisamy
hi
I am subscribing data in command mode , the snapshot data is from api call and if it fails we want to make sure the retry occurs atleast when next client connect.
so if we do clearnsnapshot and issue unsubscribe call.
does it trigger the subscribe method.
Our only intention is to connect data adapter somehow for the second client onwards. We knew that meta adapter get notifies but we want to understand does data adapter gets any callback upon subsequent client subscriptions?
Dario Crivelli
Hi, We confirm that the Data Adapter is not notified of client activity (which is the job of the Metadata Adapter instead).
This separation of concerns is by design.
The invocation of clearSnapshot doesn't affect the subscription lifecycle but only the data flow (in COMMAND mode it is equivalent to issuing DELETE for all current keys).
Likewise, invoking unsubscribe from the Adapter to itself has no effect on the Server behavior.
If the collection of the snapshot upon subscribe fails, you should retry immediately (or after a proper timeout).
Once the snapshot finally arrives, you can provide it immediately to the Server; it will be send to the first client and it will be ready to be sent to the second client when it arrives.
If you prefer to wait for the second client to subscribe (while the first is still connected), then you can't but ask for the collaboration of the Metadata Adapter, which is the owner of this information.