client/src/app/core/routing/custom-reuse-strategy.ts

   1 import { Injectable } from '@angular/core'
   2 import { ActivatedRouteSnapshot, DetachedRouteHandle, RouteReuseStrategy } from '@angular/router'
   3 import { RouterSetting } from './'
   4 import { PeerTubeRouterService } from './peertube-router.service'
   5
   6 @Injectable()
   7 export class CustomReuseStrategy implements RouteReuseStrategy {
   8   storedRouteHandles = new Map<string, DetachedRouteHandle>()
   9   recentlyUsed: string
  10
  11   private readonly MAX_SIZE = 2
  12
  13   // Decides if the route should be stored
  14   shouldDetach (route: ActivatedRouteSnapshot): boolean {
  15     return this.isReuseEnabled(route)
  16   }
  17
  18   // Store the information for the route we're destructing
  19   store (route: ActivatedRouteSnapshot, handle: DetachedRouteHandle): void {
  20     if (!handle) return
  21
  22     const key = this.generateKey(route)
  23     this.recentlyUsed = key
  24
  25     console.log('Storing component %s to reuse later.', key);
  26
  27     (handle as any).componentRef.instance.disableForReuse()
  28
  29     this.storedRouteHandles.set(key, handle)
  30
  31     this.gb()
  32   }
  33
  34   // Return true if we have a stored route object for the next route
  35   shouldAttach (route: ActivatedRouteSnapshot): boolean {
  36     const key = this.generateKey(route)
  37     return this.isReuseEnabled(route) && this.storedRouteHandles.has(key)
  38   }
  39
  40   // If we returned true in shouldAttach(), now return the actual route data for restoration
  41   retrieve (route: ActivatedRouteSnapshot): DetachedRouteHandle {
  42     if (!this.isReuseEnabled(route)) return undefined
  43
  44     const key = this.generateKey(route)
  45     this.recentlyUsed = key
  46
  47     console.log('Reusing component %s.', key)
  48
  49     const handle = this.storedRouteHandles.get(key)
  50     if (!handle) return handle;
  51
  52     (handle as any).componentRef.instance.enabledForReuse()
  53
  54     return handle
  55   }
  56
  57   // Reuse the route if we're going to and from the same route
  58   shouldReuseRoute (future: ActivatedRouteSnapshot, curr: ActivatedRouteSnapshot): boolean {
  59     return future.routeConfig === curr.routeConfig
  60   }
  61
  62   private gb () {
  63     if (this.storedRouteHandles.size >= this.MAX_SIZE) {
  64       this.storedRouteHandles.forEach((r, key) => {
  65         if (key === this.recentlyUsed) return
  66
  67         console.log('Removing stored component %s.', key);
  68
  69         (r as any).componentRef.destroy()
  70         this.storedRouteHandles.delete(key)
  71       })
  72     }
  73   }
  74
  75   private generateKey (route: ActivatedRouteSnapshot) {
  76     const reuse = route.data.reuse
  77     if (!reuse) return undefined
  78
  79     return reuse.key + JSON.stringify(route.queryParams)
  80   }
  81
  82   private isReuseEnabled (route: ActivatedRouteSnapshot) {
  83     // Cannot use peertube router here because of cyclic router dependency
  84     return route.data.reuse?.enabled &&
  85       !!(route.queryParams[PeerTubeRouterService.ROUTE_SETTING_NAME] & RouterSetting.REUSE_COMPONENT)
  86   }
  87 }