🟠 Effect vs Selector
For this exercise, you will have a dashboard of activities displaying the name, the main teacher and a list of subtitutes.
Information
In NgRx, selectors is a very powerful tool often misused. You should use them as soon as you need to transform an already existing data in the store.
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You shouldn’t store derived state. This is error prone because when your data changes, you will have to change it at multiple places => you should have only one place of truth with that data, and every transformation should be done in a selector.
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Inside a component, you shouldn’t transform a selector (using map operator), or you shouldn’t have to call a selector from a function in your view. The useful data for a component should be done in a selector.
Statement
You will have to Refactor this working example of a dashboard of activities.
Contraints:
- Only one action should be dispatched from a component
- Status effect is useless. Using combineLatest should be a red flag. And Effect are made for side effect, not transforming data. That’s a selector role
- Status state might not be useful, it’s only a derived state of existing state.