async-injection/lib/decorators.d.ts

A robust lightweight dependency injection library for TypeScript.

import { InjectableId } from './injector';
/**
 * Placed just before the class declaration, this class decorator applies metadata to the class constructor indicating that the user intends to bind the class into the container.
 * This decorator will throw if not placed on a class declaration, or if placed more than once on a class declaration.
 */
export declare function Injectable(): ClassDecorator;
/**
 * Placed just before a constructor parameter, this parameter decorator allows for specificity and control over the type of Object that will be injected into the parameter.
 * In the absence of this decorator the container will use whatever is bound to a parameter's type (or throw an error if it is unable to recognize the type).
 * This decorator may also be placed on a parameter of a method annotated with @PostConstruct, in which case the container will resolve and inject the value before invoking that method.
 *
 * @param id  The identifier of the bound type that should be injected.
 */
export declare function Inject(id: InjectableId<any>): ParameterDecorator;
/**
 * This is a helper function used by the container to retrieve the @Inject metadata for a specifically indexed constructor parameter
 *
 * @param target  The constructor function of the class (we don't allow @Inject on anything else).
 * @param parameterIndex    The ordinal index of the parameter in the constructor’s parameter list
 * @see Inject
 */
export declare function _getInjectedIdAt(target: Function, parameterIndex: number): InjectableId<any>;
/**
 * Retrieve the @Inject metadata for a specifically indexed parameter of a named method.
 */
export declare function _getInjectedIdForMethod(prototype: object, methodName: string | symbol, parameterIndex: number): InjectableId<any>;
/**
 * Placed just before a constructor parameter, this parameter decorator signals the container that it should supply the 'alt' constant value (undefined by default) if for *any* reason it is unable to otherwise resolve the type of the parameter.
 * This decorator may also be placed on a parameter of a method annotated with @PostConstruct.
 * WARNING!  It is your responsibility to ensure that alt is of the appropriate type/value.
 */
export declare function Optional(alt?: any): ParameterDecorator;
/**
 * This is a helper function used by the container to retrieve the @Optional metadata for a specifically indexed constructor parameter
 *
 * @param target  The constructor function of the class (we don't allow @Optional on anything else).
 * @param parameterIndex    The ordinal index of the parameter in the constructor’s parameter list
 * @see Optional
 * @returns an object containing the value provided in the decorator, or undefined if no annotation was present.
 */
export declare function _getOptionalDefaultAt(target: Function, parameterIndex: number): {
    value: any;
};
/**
 * Retrieve the @Optional metadata for a specifically indexed parameter of a named method.
 */
export declare function _getOptionalDefaultForMethod(prototype: object, methodName: string | symbol, parameterIndex: number): {
    value: any;
};
/**
 * Placed just before a class method, this method decorator flags a method that should be called after an object has been instantiated by the container, but before it is put into service.
 * The method will be assumed to be synchronous unless the method signature explicitly declares its return type to be ": Promise<something>".
 * Parameters will be resolved by the container just as they are for constructors.
 * This decorator will throw if placed on a non-method or a static method of a class, or if placed on a method more than once, or if placed on more than one method for a class.
 */
export declare function PostConstruct(): MethodDecorator;
/**
 * Placed just before a class method, this decorator identifies a method which should be called when an object is removed from service.
 * If invoked by the container, the container will drop any references it has to the object when the method returns.
 * Note that this decorator is *not* a guarantee (or even an implication) that the decorated method will be called (JavaScript has no mechanism to enforce such a contract).
 * This decorator simply serves as a flag to indicate a method which is intended to clean up resources allocated by the object *which would not otherwise be garbage collected*.
 * You should *not* use this decorator as a general "object finalization" method.  It has very limited scope and purpose.
 * The decorated method must complete normally (no throwing), as "release" is not an abort-able process.
 * This decorator will throw if placed on a non-method or a static method of a class, or if placed on a method more than once, or if placed on more than one method for a class.
 * The @see InvokeReleaseMethod helper function can search for and invoke the @Release decorated method of an object.
 * Also @see Container.releaseSingletons for the intended usage of this decorator.
 * It is intended that after the @Release decorated method of an object is called, that object will not be used again, but this is of course not enforced).
 */
export declare function Release(): MethodDecorator;