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Inter Module communication

As a developer, i am developing a module that wants to communicate with other modules. This describes uses for event bus messaging between modules

EventBus​

@shiksha/common-lib provides EventBus that is used to communicate and event that happened. Any other module can subscribes to the event channel and act on event that has happened.

Publish an Event​

\ A component A in a module M1 publishes event E

\\ -- componentA.js
import {eventBus} from '@shiksha/common-lib';
...
let eventData = ...
eventBus.publish(
              "[channel]" , 
              {
                eventType:"[eventtype]", 
                data: eventData 
              });
...

Subscribes to an Event​

\ A component B in module M2 wants to act on an event that is published to a channel 

\\ -- componentB.js
import {eventBus} from '@shiksha/common-lib';
...
\\ grab subscription 
\\ so that it can be released after component no more wants to listen to the events in the channel
const subscription = eventBus.subscribe("[channel]", (data, envelop)=>{
      console.log(envelop);
      if(data.eventType="[eventtype]"){
        // act on event wiith data.
        ...
      }
    });
...

// unscubscribe when componentB is destroyed/removed
eventBus.unsubscribe(subscription);