client/src/app/videos/recommendations/recent-videos-recommendation.service.ts

   1 import { Inject, Injectable } from '@angular/core'
   2 import { RecommendationService } from '@app/videos/recommendations/recommendations.service'
   3 import { Video } from '@app/shared/video/video.model'
   4 import { VideoService, VideosProvider } from '@app/shared/video/video.service'
   5 import { map } from 'rxjs/operators'
   6 import { Observable } from 'rxjs'
   7
   8 /**
   9  * Provides "recommendations" by providing the most recently uploaded videos.
  10  */
  11 @Injectable()
  12 export class RecentVideosRecommendationService implements RecommendationService {
  13
  14   readonly pageSize = 5
  15
  16   constructor (
  17     @Inject(VideoService) private videos: VideosProvider
  18   ) {
  19   }
  20
  21   getRecommendations (uuid: string): Observable<Video[]> {
  22     return this.fetchPage(1)
  23       .pipe(
  24         map(vids => {
  25           const otherVideos = vids.filter(v => v.uuid !== uuid)
  26           return otherVideos.slice(0, this.pageSize)
  27         })
  28       )
  29   }
  30
  31   private fetchPage (page: number): Observable<Video[]> {
  32     let pagination = { currentPage: page, itemsPerPage: this.pageSize + 1 }
  33     return this.videos.getVideos(pagination, '-createdAt')
  34       .pipe(
  35         map(v => v.videos)
  36       )
  37   }
  38
  39 }