README.md

NgRx Effect vs Selector

Author: Thomas Laforge

For this exercice, 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.

• You shouldn't store derived state. This is error prone because when your data change, 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.

• 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

1. Refactor this working example of a dashboard of activities.

Rules:

• 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.

Submitting your work

1. Fork the project
2. clone it
3. npm ci
4. nx serve ngrx-1
5. ...work On it
6. Commit your work
7. Submit a PR with a title beginning with Answer:2 that I will review and other dev can review.

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