Files
dspace-angular/src/app/core/data/base/identifiable-data.service.ts
2022-09-12 12:29:04 +02:00

84 lines
4.2 KiB
TypeScript

/**
* The contents of this file are subject to the license and copyright
* detailed in the LICENSE and NOTICE files at the root of the source
* tree and available online at
*
* http://www.dspace.org/license/
*/
import { CacheableObject } from '../../cache/cacheable-object.model';
import { FollowLinkConfig } from '../../../shared/utils/follow-link-config.model';
import { Observable } from 'rxjs';
import { map } from 'rxjs/operators';
import { RemoteData } from '../remote-data';
import { BaseDataService } from './base-data.service';
import { RequestService } from '../request.service';
import { RemoteDataBuildService } from '../../cache/builders/remote-data-build.service';
import { ObjectCacheService } from '../../cache/object-cache.service';
import { HALEndpointService } from '../../shared/hal-endpoint.service';
/**
* Shorthand type for the method to construct an ID endpoint.
*/
export type ConstructIdEndpoint = (endpoint: string, resourceID: string) => string;
/**
* The default method to construct an ID endpoint
*/
export const constructIdEndpointDefault = (endpoint, resourceID) => `${endpoint}/${resourceID}`;
/**
* A type of data service that deals with objects that have an ID.
*
* The effective endpoint to use for the ID can be adjusted by providing a different {@link ConstructIdEndpoint} method.
* This method is passed as an argument so that it can be set on data service features without having to override them.
*/
export class IdentifiableDataService<T extends CacheableObject> extends BaseDataService<T> {
constructor(
protected linkPath: string,
protected requestService: RequestService,
protected rdbService: RemoteDataBuildService,
protected objectCache: ObjectCacheService,
protected halService: HALEndpointService,
protected responseMsToLive?: number,
protected constructIdEndpoint: ConstructIdEndpoint = constructIdEndpointDefault,
) {
super(linkPath, requestService, rdbService, objectCache, halService, responseMsToLive);
}
/**
* Returns an observable of {@link RemoteData} of an object, based on its ID, with a list of
* {@link FollowLinkConfig}, to automatically resolve {@link HALLink}s of the object
* @param id ID of object we want to retrieve
* @param useCachedVersionIfAvailable If this is true, the request will only be sent if there's
* no valid cached version. Defaults to true
* @param reRequestOnStale Whether or not the request should automatically be re-
* requested after the response becomes stale
* @param linksToFollow List of {@link FollowLinkConfig} that indicate which
* {@link HALLink}s should be automatically resolved
*/
findById(id: string, useCachedVersionIfAvailable = true, reRequestOnStale = true, ...linksToFollow: FollowLinkConfig<T>[]): Observable<RemoteData<T>> {
const href$ = this.getIDHrefObs(encodeURIComponent(id), ...linksToFollow);
return this.findByHref(href$, useCachedVersionIfAvailable, reRequestOnStale, ...linksToFollow);
}
/**
* Create the HREF for a specific object based on its identifier; with possible embed query params based on linksToFollow
* @param endpoint The base endpoint for the type of object
* @param resourceID The identifier for the object
* @param linksToFollow List of {@link FollowLinkConfig} that indicate which {@link HALLink}s should be automatically resolved
*/
getIDHref(endpoint, resourceID, ...linksToFollow: FollowLinkConfig<T>[]): string {
return this.buildHrefFromFindOptions(this.constructIdEndpoint(endpoint, resourceID), {}, [], ...linksToFollow);
}
/**
* Create an observable for the HREF of a specific object based on its identifier
* @param resourceID The identifier for the object
* @param linksToFollow List of {@link FollowLinkConfig} that indicate which {@link HALLink}s should be automatically resolved
*/
getIDHrefObs(resourceID: string, ...linksToFollow: FollowLinkConfig<T>[]): Observable<string> {
return this.getEndpoint().pipe(
map((endpoint: string) => this.getIDHref(endpoint, resourceID, ...linksToFollow)));
}
}