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Injection Scope

All injectables are defined within a scope. Just like all other dependency injection frameworks, SenseJS provides the following injection scopes:

  • SINGLETON: Injectables within this scope will be instantiated only once during the application lifetime.

  • SESSION: Injectables within this scope will be instantiated once in each dependency injection session, which is usually the lifecycle of a request. It is also the default scope of a component if unspecified

  • TRANSIENT: Injectables within this scope are instantiated each time for each param it bound to; if more than one param bound to such an injectable, multiple instances of it will be created.

To specify the scope of a component, you can use the @Scope() decorator, for example:


@Component()
@Scope(Scope.SINGLETON)
class SingletonComponent {

  myMethod() {
    //...
  }
}

For injectables provided by a factory, the scope is specified by their provider:

const MyModule = createModule({
  factories: [{
    provide: MyInjectable,
    factory: MyFactory,
    scope: Scope.SINGLETON
  }]
});

While constant injectables are always SINGLETON scoped.