Finish to refactor

dashboard/src/app/els.service.ts

@@ -202,8 +202,7 @@ export class ElsService {
               },
               'size': 0
             }), {headers: this.headers})
-      .map(res => res.json().aggregations.genres.buckets)
-      .map((hits: Array<any>) => this.hitsToBuckets(hits));
+      .map(res => this.responseAggregationToBucket(res, 'genres'));
   }
 
   getGenreCount(): Observable<number> {
@@ -245,9 +244,8 @@ export class ElsService {
               },
               'size': 0
           }), {headers: this.headers})
-      .map(res => res.json().aggregations.album.buckets)
+      .map(res => this.responseAggregationToBucket(res, 'album'));
       // TODO Take in consideration "sum_other_doc_count"
-      .map((hits: Array<any>) => this.hitsToBuckets(hits));
   }
 
   getArtistFromAlbumName(albumname: string): Observable<Album[]> {
@@ -304,12 +302,17 @@ export class ElsService {
     return result;
   }
 
-  private hitsToBuckets(hits: Array<any>): Bucket[] {
-      const result: Array<Bucket> = [];
-      hits.forEach((bucket) => {
-        result.push(bucket);
-      });
-      return result;
+  /** Process an aggregation response to an array of Bucket.
+   *
+   * @param res Response to process
+   * @param name Name of aggregation
+   */
+  private responseAggregationToBucket(res: Response, name: string): Bucket[] {
+    const result: Array<Bucket> = [];
+    res.json().aggregations[name].buckets.forEach((bucket) => {
+      result.push(bucket);
+    });
+    return result;
   }
 
   private handleError(error: any): Promise<any> {