Hi all,

The following changes were proposed to CEP 3.0.0 to improve the usability
of CEP.

1) EventStream UI is the central place to store all the event streams.
Event stream management will be decoupled from the EB/EF/EP components and
a separate component will be created to manage event streams.

2) Execution Plan UI is the main UI that user is going to use. It will
popup a dialog to create event streams if a new event stream is needed. It
will also pop up event builder creation dialog and event formatter creation
dialog if it is needed for the user.

But it will not store any values in the backend until the execution plan is
saved and will save all the related configurations once as an atomic
transaction.

The saving of the execution plan can include the following sub steps.

1. Create a related event-builder (optional)

2. Create an execution plan (mandatory)

3. Create related event-formatters (optional)

4. Create stream definitions

Out of the above sub steps, only step 4 will be persisted to the backend
immediately (since stream definitions are independent from the flow
configuration). Persisting configuration of sub steps 1-3 would go to
backend at once and the event-processor component will have the
responsibility of creating the needed event-builders/formatters and ensure
the wiring of the flow properly.

Also, for the case of custom mapping for event builders, changing the event
builder mapping will effectively change the stream definition that is
exported by the event builder. Since this stream definition is managed by
another component, I think we would have to decide on a policy on whether
we cascade changes for a builder or not. Some possible options regarding
this will be

1. When event builder mapping is changed, the exported stream definition
will change

2. When the event builder mapping is changed, we force the user to change
the associated streamdef name or version

Similarly, when changing the stream definition, we would need to decide how
the changes will be handled by the separate components.

We would also have to address the issue of the event processor component
attempting to deploy artifacts related to two other components in a
transactional manner as well.

Please share your thoughts/suggestions on the proposed changes.

@Mohan, Rajeev, Suho - Please add if I’ve missed anything from the changes
discussed.


Thanks,

Lasantha


-- 
*Lasantha Fernando*
Software Engineer - Data Technologies Team
WSO2 Inc. http://wso2.com

email: [email protected]
mobile: (+94) 71 5247551
_______________________________________________
Architecture mailing list
[email protected]
https://mail.wso2.org/cgi-bin/mailman/listinfo/architecture

Reply via email to