org.eclipse.mdm.nucleus/org.eclipse.mdm.application/src/main/webapp/src/app/localization/localization.service.ts

/********************************************************************************
 * Copyright (c) 2015-2020 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 ********************************************************************************/


import {Injectable} from '@angular/core';
import {Http, Response} from '@angular/http';
import {Localization} from './localization';
import {Node} from '../navigator/node';
import {NodeService} from '../navigator/node.service';
import {PropertyService} from '../core/property.service';
import {HttpErrorHandler} from '../core/http-error-handler';
import {MDMNotificationService} from '../core/mdm-notification.service';
import {forkJoin as observableForkJoin, Observable} from 'rxjs';
import {catchError, mergeMap, publishReplay, refCount, map} from 'rxjs/operators';

@Injectable()
export class LocalizationService {

  private _nodeUrl: string;

  private cache: Observable<Localization[]>;

  constructor(private http: Http,
              private httpErrorHandler: HttpErrorHandler,
              private _prop: PropertyService,
              private _node: NodeService,
              private notificationService: MDMNotificationService) {

    this._nodeUrl = _prop.getUrl('mdm/environments');
  }

  // Caches valueLists if cache is empty. Then returns observable containing cached valueLists.
  getLocalizations() {
    if (!this.cache) {
      this.cache = this._node.getNodes(undefined).pipe(
                mergeMap(envs => this.initLocalizations(envs)),
                publishReplay(1),
                refCount());
    }
    return this.cache;
  }

  private initLocalizations(envs: Node[]) {
    return observableForkJoin(envs.map(env => this.getLocalization(env))).pipe(
                     map(locs => locs.reduce((a, b) => a.concat(b), [])));
  }

  private getLocalization(node: Node): Observable<Localization[]> {
    let url = this._nodeUrl + '/' + node.sourceName;
    if (node.sourceType === 'Environment') {
      url = url + '/localizations?all=true';
    } else {
      url = url + '/' + node.type.toLowerCase() + 's/localizations';
    }
    return this.get(url);
  }

  private get(url: string) {
    return this.http.get(url).pipe(
    map(res => <Localization[]> res.json().data),
    catchError(this.httpErrorHandler.handleError));
  }
}