Aftermath and CQRS

[vadymmarkov]

@zenangst @RamonGilabert @onmyway133

Some ideas were taken from CQRS https://en.wikipedia.org/wiki/Command–query_separation principle, but in general there is at least one fundamental difference - we don't separate a query layer that only returns data to the caller and a command layer that only updates the state. Aftermath is for front-end apps where both read and update actions go through the same flow:

Command -> Handler -> Event -> Reaction

With that being said, should we care about terms that could potentially lead people into confusion? For example, Command could be renamed to Intent or even Action.

[onmyway133]

@vadymmarkov What does Command do in this flow?

[vadymmarkov]

@onmyway133 Command is any kind of request from the view, could be "Load posts" or "Update post". It's handled by CommandHandler where all the business logic is, such as networking or database queries. When CommandHandler is done, it produces some response, either success or error, and publishes it to single/multiple event subscribers.

[zenangst]

We could go with Action to avoid confusion.

[zenangst]

Ops, I totally closed by mistake, stupid jumpy subway ride.

[vadymmarkov]

I was thinking about it and for me "Load post!" or "Update post!" are more commands than actions. So let's not make a problem from it, leave Command as a name and see how it goes.

[zenangst]

I do agree with you here, but if you think about the flow that you referred to before;

Command -> Handler -> Event -> Reaction

The end result of an action is a reaction right? 😁