angular/packages/core/src/di/provider.ts

329 lines
8.8 KiB
TypeScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
import {Type} from '../type';
/**
* @whatItDoes Configures the {@link Injector} to return a value for a token.
* @howToUse
* ```
* const provider: ValueProvider = {provide: 'someToken', useValue: 'someValue'};
* ```
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='ValueProvider'}
*
* @stable
*/
export interface ValueProvider {
/**
* An injection token. (Typically an instance of `Type` or `InjectionToken`, but can be `any`).
*/
provide: any;
/**
* The value to inject.
*/
useValue: any;
/**
* If true, then injector returns an array of instances. This is useful to allow multiple
* providers spread across many files to provide configuration information to a common token.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='MultiProviderAspect'}
*/
multi?: boolean;
}
/**
* @whatItDoes Configures the {@link Injector} to return an instance of `useClass` for a token.
* @howToUse
* ```
* @Injectable()
* class MyService {}
*
* const provider: ClassProvider = {provide: 'someToken', useClass: MyService, deps: []};
* ```
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='StaticClassProvider'}
*
* Note that following two providers are not equal:
* {@example core/di/ts/provider_spec.ts region='StaticClassProviderDifference'}
*
* @stable
*/
export interface StaticClassProvider {
/**
* An injection token. (Typically an instance of `Type` or `InjectionToken`, but can be `any`).
*/
provide: any;
/**
* An optional class to instantiate for the `token`. (If not provided `provide` is assumed to be a
* class to
* instantiate)
*/
useClass: Type<any>;
/**
* A list of `token`s which need to be resolved by the injector. The list of values is then
* used as arguments to the `useClass` constructor.
*/
deps: any[];
/**
* If true, then injector returns an array of instances. This is useful to allow multiple
* providers spread across many files to provide configuration information to a common token.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='MultiProviderAspect'}
*/
multi?: boolean;
}
/**
* @whatItDoes Configures the {@link Injector} to return an instance of a token.
* @howToUse
* ```
* @Injectable()
* class MyService {}
*
* const provider: ClassProvider = {provide: MyClass, deps: []};
* ```
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='ConstructorProvider'}
*
* @stable
*/
export interface ConstructorProvider {
/**
* An injection token. (Typically an instance of `Type` or `InjectionToken`, but can be `any`).
*/
provide: Type<any>;
/**
* A list of `token`s which need to be resolved by the injector. The list of values is then
* used as arguments to the `useClass` constructor.
*/
deps: any[];
/**
* If true, then injector returns an array of instances. This is useful to allow multiple
* providers spread across many files to provide configuration information to a common token.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='MultiProviderAspect'}
*/
multi?: boolean;
}
/**
* @whatItDoes Configures the {@link Injector} to return a value of another `useExisting` token.
* @howToUse
* ```
* const provider: ExistingProvider = {provide: 'someToken', useExisting: 'someOtherToken'};
* ```
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='ExistingProvider'}
*
* @stable
*/
export interface ExistingProvider {
/**
* An injection token. (Typically an instance of `Type` or `InjectionToken`, but can be `any`).
*/
provide: any;
/**
* Existing `token` to return. (equivalent to `injector.get(useExisting)`)
*/
useExisting: any;
/**
* If true, then injector returns an array of instances. This is useful to allow multiple
* providers spread across many files to provide configuration information to a common token.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='MultiProviderAspect'}
*/
multi?: boolean;
}
/**
* @whatItDoes Configures the {@link Injector} to return a value by invoking a `useFactory`
* function.
* @howToUse
* ```
* function serviceFactory() { ... }
*
* const provider: FactoryProvider = {provide: 'someToken', useFactory: serviceFactory, deps: []};
* ```
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='FactoryProvider'}
*
* Dependencies can also be marked as optional:
* {@example core/di/ts/provider_spec.ts region='FactoryProviderOptionalDeps'}
*
* @stable
*/
export interface FactoryProvider {
/**
* An injection token. (Typically an instance of `Type` or `InjectionToken`, but can be `any`).
*/
provide: any;
/**
* A function to invoke to create a value for this `token`. The function is invoked with
* resolved values of `token`s in the `deps` field.
*/
useFactory: Function;
/**
* A list of `token`s which need to be resolved by the injector. The list of values is then
* used as arguments to the `useFactory` function.
*/
deps?: any[];
/**
* If true, then injector returns an array of instances. This is useful to allow multiple
* providers spread across many files to provide configuration information to a common token.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='MultiProviderAspect'}
*/
multi?: boolean;
}
/**
* @whatItDoes Describes how the {@link Injector} should be configured in a static way (Without
* reflection).
* @howToUse
* See {@link ValueProvider}, {@link ExistingProvider}, {@link FactoryProvider}.
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* @stable
*/
export type StaticProvider = ValueProvider | ExistingProvider | StaticClassProvider |
ConstructorProvider | FactoryProvider | any[];
/**
* @whatItDoes Configures the {@link Injector} to return an instance of `Type` when `Type' is used
* as token.
* @howToUse
* ```
* @Injectable()
* class MyService {}
*
* const provider: TypeProvider = MyService;
* ```
*
* @description
*
* Create an instance by invoking the `new` operator and supplying additional arguments.
* This form is a short form of `TypeProvider`;
*
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='TypeProvider'}
*
* @stable
*/
export interface TypeProvider extends Type<any> {}
/**
* @whatItDoes Configures the {@link Injector} to return an instance of `useClass` for a token.
* @howToUse
* ```
* @Injectable()
* class MyService {}
*
* const provider: ClassProvider = {provide: 'someToken', useClass: MyService};
* ```
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='ClassProvider'}
*
* Note that following two providers are not equal:
* {@example core/di/ts/provider_spec.ts region='ClassProviderDifference'}
*
* @stable
*/
export interface ClassProvider {
/**
* An injection token. (Typically an instance of `Type` or `InjectionToken`, but can be `any`).
*/
provide: any;
/**
* Class to instantiate for the `token`.
*/
useClass: Type<any>;
/**
* If true, then injector returns an array of instances. This is useful to allow multiple
* providers spread across many files to provide configuration information to a common token.
*
* ### Example
*
* {@example core/di/ts/provider_spec.ts region='MultiProviderAspect'}
*/
multi?: boolean;
}
/**
* @whatItDoes Describes how the {@link Injector} should be configured.
* @howToUse
* See {@link TypeProvider}, {@link ClassProvider}, {@link StaticProvider}.
*
* @description
* For more details, see the {@linkDocs guide/dependency-injection "Dependency Injection Guide"}.
*
* @stable
*/
export type Provider =
TypeProvider | ValueProvider | ClassProvider | ExistingProvider | FactoryProvider | any[];