Hi Devs, Started doing $subject. The Event Receiver model was designed when Stratos cannot be run on a single JVM, and it was not properly re-factored once the Stratos single JVM distribution came up. So, all the main components (Stratos Manager, Cloud Controller, Autoscaler) has their own Message Queues, Event Listeners, Processors and Processor Chains. However, the Topology model is a common to all the components, therefore the we actually have three sets of classes as mentioned above, updating the Topology. This is unnecessary, the code is complex and hard to maintain.
This can be changed so that each JVM will have only a single set of Message Queues, Event Listeners, Processors and Processor Chains of each event type. All the other component who are interested in a particular event can access the event receiver object and call addEventListener method to register a listener to get notified on the relevant events. The following are the main changes: 1. Make all *EventReceiver classes singleton; Stratos will have one Event Receiver for main event categories (Topology, Tenant, Instance Status, Instance Notifier, Initializer, Health Stat, Domain Mapping, Cluster Status, Application and Signup) per JVM. 2. Remove the multiple EventReceivers in the components (ex:. StratosManagerTopologyEventReceiver, AutoscalerHealthStatEventReceiver, etc.). Instead of creating multiple queues, delegators, processors and processor chains, they will now act like listeners for each processor. 3. Rename the component specific event receiver classes to reflect their actual functionality. WDYT? -- Thanks and Regards, Isuru H. +94 716 358 048* <http://wso2.com/>*
