ceph/src/pybind/mgr/dashboard/frontend/src/app/shared/services/motd-notification.service.ts

   1 import { Injectable, OnDestroy } from '@angular/core';
   2
   3 import * as _ from 'lodash';
   4 import { BehaviorSubject, EMPTY, Observable, of, Subscription } from 'rxjs';
   5 import { catchError, delay, mergeMap, repeat, tap } from 'rxjs/operators';
   6
   7 import { Motd, MotdService } from '~/app/shared/api/motd.service';
   8 import { whenPageVisible } from '../rxjs/operators/page-visibilty.operator';
   9
  10 @Injectable({
  11   providedIn: 'root'
  12 })
  13 export class MotdNotificationService implements OnDestroy {
  14   public motd$: Observable<Motd | null>;
  15   public motdSource = new BehaviorSubject<Motd | null>(null);
  16
  17   private subscription: Subscription;
  18   private localStorageKey = 'dashboard_motd_hidden';
  19
  20   constructor(private motdService: MotdService) {
  21     this.motd$ = this.motdSource.asObservable();
  22     // Check every 60 seconds for the latest MOTD configuration.
  23     this.subscription = of(true)
  24       .pipe(
  25         mergeMap(() => this.motdService.get()),
  26         catchError((error) => {
  27           // Do not show an error notification.
  28           if (_.isFunction(error.preventDefault)) {
  29             error.preventDefault();
  30           }
  31           return EMPTY;
  32         }),
  33         tap((motd: Motd | null) => this.processResponse(motd)),
  34         delay(60000),
  35         repeat(),
  36         whenPageVisible()
  37       )
  38       .subscribe();
  39   }
  40
  41   ngOnDestroy(): void {
  42     this.subscription.unsubscribe();
  43   }
  44
  45   hide() {
  46     // Store the severity and MD5 of the current MOTD in local or
  47     // session storage to be able to show it again if the severity
  48     // or message of the latest MOTD has changed.
  49     const motd: Motd = this.motdSource.getValue();
  50     if (motd) {
  51       const value = `${motd.severity}:${motd.md5}`;
  52       switch (motd.severity) {
  53         case 'info':
  54           localStorage.setItem(this.localStorageKey, value);
  55           sessionStorage.removeItem(this.localStorageKey);
  56           break;
  57         case 'warning':
  58           sessionStorage.setItem(this.localStorageKey, value);
  59           localStorage.removeItem(this.localStorageKey);
  60           break;
  61       }
  62     }
  63     this.motdSource.next(null);
  64   }
  65
  66   processResponse(motd: Motd | null) {
  67     const value: string | null =
  68       sessionStorage.getItem(this.localStorageKey) || localStorage.getItem(this.localStorageKey);
  69     let visible: boolean = _.isNull(value);
  70     // Force a hidden MOTD to be shown again if the severity or message
  71     // has been changed.
  72     if (!visible && motd) {
  73       const [severity, md5] = value.split(':');
  74       if (severity !== motd.severity || md5 !== motd.md5) {
  75         visible = true;
  76         sessionStorage.removeItem(this.localStorageKey);
  77         localStorage.removeItem(this.localStorageKey);
  78       }
  79     }
  80     if (visible) {
  81       this.motdSource.next(motd);
  82     }
  83   }
  84 }