gparlakov / ng-gotchas

Some angular gotchas I've found:

NgGotchas

NgOnDestroy does not get called

An example app showcasing ng-gotcha # 1

1. Implemented a service. App-wide one - gets provided in AppModule. Eagerly i.e. at app start, before components get loaded.
2. Inject service in TimeWidgetComponent. Service is provided in AppModule
3. Destroy component
4. Expect service to get destroyed?
5. It is not destroyed.

Alternative

2. Inject service in FeedComponent provided in FeedComponent
3. Destroy component
4. Expect service to get destroyed?
5. It does get destroyed?

WAT?

My take on that:

• FeedComponent provides the service and component does get destroyed and in turn it destroys its 'destructable' providers
• AppModule provides the service but never gets destroyed until user navigates away from our site at which point the Garbage collector is responsible for eventually cleaning that memory

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Ng Cli Readme

This project was generated with Angular CLI version 1.6.8.

Development server

Run ng serve for a dev server. Navigate to http://localhost:4200/. The app will automatically reload if you change any of the source files.

Code scaffolding

Run ng generate component component-name to generate a new component. You can also use ng generate directive|pipe|service|class|guard|interface|enum|module.

Build

Run ng build to build the project. The build artifacts will be stored in the dist/ directory. Use the -prod flag for a production build.

Running unit tests

Run ng test to execute the unit tests via Karma.

Running end-to-end tests

Run ng e2e to execute the end-to-end tests via Protractor.

Further help

To get more help on the Angular CLI use ng help or go check out the Angular CLI README.