Add Callback on deletion in LwM2mInstanceEnabler

[versatildefuy]

Hi guys,

first, thank you for your effort :)
We are working in a use case using both client and server. We are trying to disable an external component in the device when an instance is deleted, but I wasn't able to find any kind of callback or class for that without importing and adapting leshan-client-core and leshan-client-cf. A solution is reached modifying ObjectEnabler.class create and delete methods.
Is there any other way to handle these events?

[sbernard31]

You are implementing a LwM2mInstanceEnabler and you would like to execute some code when the instance is deleted ?

I'm afraid there is nothing like this for now, but this could be a good improvement.

Waiting something like this was implementing (or contributing) you can create your own LwM2mObjectEnabler from BaseObjectEnabler (if you don't need the LwM2mInstanceEnabler) or from ObjectEnabler (if you still want to use LwM2mInstanceEnabler).

[versatildefuy]

Maybe the easiest way could be implementing a setter in ObjectsInitializer.class with the ObjectEnabler for the object as a parameter.

[sbernard31]

If you create your own LwM2mObjectEnabler you didn't really need ObjectsInitializer.

Just add it to the collection manually :

initializer.setClassForObject(DEVICE, MyDevice.class);
initializer.setInstancesForObject(LOCATION, locationInstance);
//  .... ....
List<LwM2mObjectEnabler> enablers = initializer.create(SECURITY, SERVER, DEVICE, LOCATION);
// add your custom LwM2mObjectEnabler
enablers.add(new MyCustomObjectEnabler());

LeshanClientBuilder builder = new LeshanClientBuilder(endpoint);
builder.setObjects(enablers);
builder.build();

Just to know, is adding a onDelete() method on LwM2mInstanceEnabler would help ?

[versatildefuy]

Just to know, is adding a onDelete() method on LwM2mInstanceEnabler would help ?

Yes, that would solve my problem

[sbernard31]

I created a PR #641 to add onDelete().
Feedback would be really appreciated.

[sbernard31]

#641 is now integrated in master so we can close this issue.