The Observer Pattern In Apex

Let's use the observer pattern to build a pub-sub type application in the Salesforce Apex programming language.
github.com/bdJ...

[@dzmitryvarabei6700]

I think observerCollection property wan't implemented in ProductSubject class. How it was intended to use this property? And sorry if it was explained in the video, I just didn't catch.

[@softwareengineeringandsale4005]

I think i did a bad job with this. Because there was only one type in the video i skipped it.

[@PuerinTheHunter]

Brooks, that ProductObserver.notify() is running a query, but it is called from ProductSubject.notifyObservers() and that itself is called from within a loop in ProductCatalogTriggerHandler. The result is a query within a loop which should be avoided.

[@softwareengineeringandsale4005]

You are totally correct and thanks for calling that out. i was so busy trying to wrap up the video I didn’t catch it.

[@olaitanadesoji3719]

I just watched the video and this is exactly what rang in my head .. Good someone else catched.. But still Great teaching moment by @Software Engineering and Salesforce

[@petargechev1852]

[@banderson5144]

This is a very nice use case of the wire adapter/decorator in LWC as well to have the call automatically happen as well. Did you think about also possibly using platform events for this scenario as well

[@softwareengineeringandsale4005]

I did and i mention in the video that platform events are another way to do this. But for simplicity’s sake i implemented with a trigger.

[@vetealaurent3380]

great stuff ! Any particular reason going asynchronous for subscribeUser() in the JS controller ?

[@softwareengineeringandsale4005]

it’s just syntactic sugar for promises. I find it easier to work with.

[@bakshirocks]

Great content as always. I have a doubt in on if your earlier design patter videos. You mentioned that abstract classes can NOT be instantiated but still you were able to instantiate the Pizza abstract class in that video. Can you please check and explain.?

[@softwareengineeringandsale4005]

Did you mean to post this one here? No abstract classes in the video.