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