Implement timed replicator

src/app/manager-dashboard/manager-sync.component.ts

@@ -1,36 +1,81 @@
-import { Component, OnInit } from '@angular/core';
+import { Component, OnInit, OnDestroy } from '@angular/core';
 import { CouchService } from '../shared/couchdb.service';
 import { DialogsLoadingService } from '../shared/dialogs/dialogs-loading.service';
-import { forkJoin } from 'rxjs';
+import { forkJoin, interval, Subscription, BehaviorSubject, pipe } from 'rxjs';
+import { catchError } from 'rxjs/operators';
+import { PlanetMessageService } from '../shared/planet-message.service';
 
 @Component({
   templateUrl: './manager-sync.component.html'
 })
 
-export class ManagerSyncComponent implements OnInit {
+export class ManagerSyncComponent implements OnInit, OnDestroy {
 
-  replicators = [];
+  private syncSubscription: Subscription;
+  private replicatorsSubject = new BehaviorSubject<any[]>([]);
+  replicators$ = this.replicatorsSubject.asObservable();
+
+  private readonly SYNC_INTERVAL = 3600000;
+  private readonly LAST_SYNC_KEY = 'lastSyncTime';
 
   constructor(
     private couchService: CouchService,
+    private planetMessageService: PlanetMessageService,
     private dialogsLoadingService: DialogsLoadingService
-  ) {}
+  ) { }
 
-  ngOnInit() {
-    this.getReplicators();
+  private timedSync() {
+    const lastSync = parseInt(localStorage.getItem(this.LAST_SYNC_KEY) || '0', 10);
+    const now = Date.now();
+
+    if (now - lastSync >= this.SYNC_INTERVAL) {
+      this.syncReplicators();
+    }
+
+    this.syncSubscription = interval(this.SYNC_INTERVAL)
+      .subscribe(() => {
+        this.syncReplicators();
+      });
   }
 
-  getReplicators() {
+  private syncReplicators() {
     this.dialogsLoadingService.start();
     forkJoin([
       this.couchService.get('_scheduler/docs'),
       this.couchService.findAll('_replicator')
     ])
+    .pipe(catchError(
+      error => {
+        this.planetMessageService.showMessage($localize`Error during synchronization ${error}`);
+        this.dialogsLoadingService.stop();
+        throw error;
+      })
+    )
     .subscribe(([ reps, data ]) => {
       const jobs = reps.docs.filter(replicator => replicator.database === '_replicator');
-      this.replicators = data.map((rep: any) => ({ ...rep, ...jobs.find(n => n.doc_id === rep._id) }));
+      const updatedReplicators = data.map((rep: any) => ({
+        ...rep,
+        ...jobs.find(n => n.doc_id === rep._id)
+      }));
+      this.replicatorsSubject.next(updatedReplicators);
       this.dialogsLoadingService.stop();
+      localStorage.setItem(this.LAST_SYNC_KEY, Date.now().toString());
     });
   }
 
+  ngOnInit() {
+    this.timedSync();
+    this.getReplicators();
+  }
+
+  getReplicators(): BehaviorSubject<any[]> {
+    return this.replicatorsSubject;
+  }
+
+  ngOnDestroy() {
+    if (this.syncSubscription) {
+      this.syncSubscription.unsubscribe();
+    }
+  }
+
 }