Module Scope

In Vona, the actual business code development is done in modules. As a relatively independent business unit, the module contains various types of resources: Config, Constant, Locale I18n, Error exception, Service, Model, Entity, etc. In order to uniformly manage these resources and facilitate the definition and use of resources, Vona provides the Scope object

Why is Vona's IOC container code more concise?

The reason is to prioritize the use of the dependency lookup strategy, resulting in fewer decorator functions and fewer type annotations. Accessing module's resources by the Scope object is one of the mechanisms for implementing dependency lookup strategies

this.scope: Obtain scope instance of the current module

All beans inherit from the base class BeanBase, thus the Scope instance of the module to which the current bean belongs can be directly obtained

src/suite/a-home/modules/home-base/src/service/menu.ts

@Service()
export class ServiceMenu extends BeanBase {
  retrieveMenus(publicPath?: string) {
    console.log(this.scope);
  }
}

• The Scope instance of the module to which the current bean belongs can be obtained through this.scope

this.$scope: Obtain scope instance cross-module

So, how to obtain Scope instances of other modules?

For example, we obtain the Scope instance of the module home-base in the module home-index:

@Controller()
class ControllerHome extends BeanBase {
  index() {
    console.log(this.$scope.homeBase);
  }
}

• The Scope instance of the module home-base can be obtained through this.$scope.homeBase

@Controller()
class ControllerHome extends BeanBase {
  index() {
    console.log(this.$scope.user);
  }
}

• If the providerId of the module name is a, such as a-user, then it can be simplified to user

app.scope

If you do not inherit from the base class BeanBase, this.scope and this.$scope cannot be used. Instead, you can use the general method:

src/backend/demo/index.ts

export async function main(app: VonaApplication, _argv: IArgv) {
  await app.bean.executor.mockCtx(async () => {
+   const scopeHomeBase = app.scope('home-base');
+   const scopeUser = app.scope('a-user');
  });
}

Members of the Scope object

Name	Description
config	Config of Module
constant	Constant of Module
locale	I18n of Module
error	Error exception of Module
service	Services of Module
model	Models of Module
entity	Entities of Module