import { ConfigParams } from '../config/ConfigParams'; import { IReconfigurable } from '../config/IReconfigurable'; import { IReferenceable } from './IReferenceable'; import { IReferences } from './IReferences'; /** * Helper class for resolving component dependencies. * * The resolver is configured to resolve named dependencies by specific locator. * During deployment the dependency locator can be changed. * * This mechanism can be used to clarify specific dependency among several alternatives. * Typically components are configured to retrieve the first dependency that matches * logical group, type and version. But if container contains more than one instance * and resolution has to be specific about those instances, they can be given a unique * name and dependency resolvers can be reconfigured to retrieve dependencies by their name. * * ### Configuration parameters ### * * dependencies: * - [dependency name 1]: Dependency 1 locator (descriptor) * - ... * - [dependency name N]: Dependency N locator (descriptor) * * ### References ### * * References must match configured dependencies. * * ### Example ### * * class MyComponent: IConfigurable, IReferenceable { * private _dependencyResolver: DependencyResolver = new DependencyResolver(); * private _persistence: IMyPersistence; * ... * * public constructor() { * this._dependencyResolver.put("persistence", new Descriptor("mygroup", "persistence", "*", "*", "1.0")); * } * * public configure(config: ConfigParams): void { * this._dependencyResolver.configure(config); * } * * public setReferences(references: IReferences): void { * this._dependencyResolver.setReferences(references); * this._persistence = this._dependencyResolver.getOneRequired("persistence"); * } * } * * // Create mycomponent and set specific dependency out of many * let component = new MyComponent(); * component.configure(ConfigParams.fromTuples( * "dependencies.persistence", "mygroup:persistence:*:persistence2:1.0" * // Override default persistence dependency * )); * component.setReferences(References.fromTuples( * new Descriptor("mygroup","persistence","*","persistence1","1.0"), new MyPersistence(), * new Descriptor("mygroup","persistence","*","persistence2","1.0"), new MyPersistence() * // This dependency shall be set * )); * * @see [[IReferences]] */ export declare class DependencyResolver implements IReferenceable, IReconfigurable { private _dependencies; private _references; /** * Creates a new instance of the dependency resolver. * * @param config (optional) default configuration where key is dependency name and value is locator (descriptor) * @param references (optional) default component references * * @see [[ConfigParams]] * @see [[configure]] * @see [[IReferences]] * @see [[setReferences]] */ constructor(config?: ConfigParams, references?: IReferences); /** * Configures the component with specified parameters. * * @param config configuration parameters to set. * * @see [[ConfigParams]] */ configure(config: ConfigParams): void; /** * Sets the component references. References must match configured dependencies. * * @param references references to set. */ setReferences(references: IReferences): void; /** * Adds a new dependency into this resolver. * * @param name the dependency's name. * @param locator the locator to find the dependency by. */ put(name: string, locator: any): void; /** * Gets a dependency locator by its name. * * @param name the name of the dependency to locate. * @returns the dependency locator or null if locator was not configured. */ private locate; /** * Gets all optional dependencies by their name. * * @param name the dependency name to locate. * @returns a list with found dependencies or empty list of no dependencies was found. */ getOptional(name: string): T[]; /** * Gets all required dependencies by their name. * At least one dependency must be present. * If no dependencies was found it throws a [[ReferenceException]] * * @param name the dependency name to locate. * @returns a list with found dependencies. * * @throws a [[ReferenceException]] if no dependencies were found. */ getRequired(name: string): T[]; /** * Gets one optional dependency by its name. * * @param name the dependency name to locate. * @returns a dependency reference or null of the dependency was not found */ getOneOptional(name: string): T; /** * Gets one required dependency by its name. * At least one dependency must present. * If the dependency was found it throws a [[ReferenceException]] * * @param name the dependency name to locate. * @returns a dependency reference * * @throws a [[ReferenceException]] if dependency was not found. */ getOneRequired(name: string): T; /** * Finds all matching dependencies by their name. * * @param name the dependency name to locate. * @param required true to raise an exception when no dependencies are found. * @returns a list of found dependencies * * @throws a [[ReferenceException]] of required is true and no dependencies found. */ find(name: string, required: boolean): T[]; /** * Creates a new DependencyResolver from a list of key-value pairs called tuples * where key is dependency name and value the depedency locator (descriptor). * * @param tuples a list of values where odd elements are dependency name and the following even elements are dependency locator (descriptor) * @returns a newly created DependencyResolver. * * @see [[fromTuplesArray]] */ static fromTuples(...tuples: any[]): DependencyResolver; }