feat(perf): improve preview loading

changelog/unreleased/enhancement-preview-loading

@@ -0,0 +1,6 @@
+Enhancement: Preview loading performance
+
+We've improved the performance of loading previews, especially for spaces.
+
+https://github.com/owncloud/web/pull/11631
+https://github.com/owncloud/ocis/issues/10054

packages/design-system/src/components/OcTable/OcTable.vue

@@ -69,6 +69,7 @@
         @dragleave.prevent="dropRowStyling(itemDomSelector(item), true, $event)"
         @mouseleave="dropRowStyling(itemDomSelector(item), true, $event)"
         @dragover="dragOver($event)"
+        @item-visible="$emit('itemVisible', item)"
       >
         <oc-td
           v-for="(field, tdIndex) in fields"
@@ -318,7 +319,8 @@ export default defineComponent({
     EVENT_TROW_MOUNTED,
     EVENT_TROW_CONTEXTMENU,
     EVENT_SORT,
-    'dropRowStyling'
+    'dropRowStyling',
+    'itemVisible'
   ],
   setup() {
     const constants = {

packages/design-system/src/components/_OcTableRow/_OcTableRow.vue

@@ -41,9 +41,10 @@ export default defineComponent({
     'dragenter',
     'dragleave',
     'dragover',
-    'mouseleave'
+    'mouseleave',
+    'itemVisible'
   ],
-  setup(props, ctx) {
+  setup(props, { emit }) {
     const observerTarget = customRef((track, trigger) => {
       let $el: HTMLElement
       return {
@@ -65,12 +66,17 @@ export default defineComponent({
     const { isVisible } = props.lazy
       ? useIsVisible({
           ...props.lazy,
-          target: observerTarget
+          target: observerTarget,
+          onVisibleCallback: () => emit('itemVisible')
         })
       : { isVisible: ref(true) }
 
     const isHidden = computed(() => !unref(isVisible))
 
+    if (!props.lazy) {
+      emit('itemVisible')
+    }
+
     return {
       observerTarget,
       isHidden,

packages/design-system/src/composables/useIsVisible/index.ts

@@ -1,13 +1,15 @@
-import { Ref, onBeforeUnmount, ref, watch } from 'vue'
+import { Ref, onBeforeUnmount, ref, unref, watch } from 'vue'
 
 export const useIsVisible = ({
   target,
   mode = 'show',
-  rootMargin = '100px'
+  rootMargin = '100px',
+  onVisibleCallback
 }: {
   target: Ref<Element>
   mode?: string
   rootMargin?: string
+  onVisibleCallback?: () => void
 }) => {
   const isSupported = window && 'IntersectionObserver' in window
   if (!isSupported) {
@@ -27,6 +29,10 @@ export const useIsVisible = ({
       const isIntersecting = intersectionObserverEntries.at(-1).isIntersecting
 
       isVisible.value = isIntersecting
+      if (unref(isVisible) && onVisibleCallback) {
+        onVisibleCallback()
+      }
+
       /**
        * if given mode is `showHide` we need to keep the observation alive.
        */

packages/web-app-files/src/components/Search/List.vue

@@ -108,7 +108,13 @@
           :fields-displayed="['name', 'size', 'tags', 'mdate']"
           :resource-dom-selector="resourceDomSelector"
           @file-click="triggerDefaultAction"
-          @row-mounted="rowMounted"
+          @item-visible="
+            loadPreview({
+              space: getMatchingSpace($event),
+              resource: $event,
+              ignoreAlmostEmptyTxtFiles: true
+            })
+          "
           @sort="handleSort"
         >
           <template #additionalResourceContent="{ resource }">
@@ -155,16 +161,12 @@ import {
   useConfigStore,
   useResourcesStore
 } from '@ownclouders/web-pkg'
-import { VisibilityObserver } from '@ownclouders/web-pkg'
-import { ImageDimension } from '@ownclouders/web-pkg'
 import { NoContentMessage } from '@ownclouders/web-pkg'
 import { ResourceTable } from '@ownclouders/web-pkg'
 import { ContextActions, FileSideBar } from '@ownclouders/web-pkg'
-import { debounce } from 'lodash-es'
 import { useGettext } from 'vue3-gettext'
 import { AppBar } from '@ownclouders/web-pkg'
 import {
-  ComponentPublicInstance,
   computed,
   defineComponent,
   nextTick,
@@ -188,7 +190,8 @@ import {
   useGetMatchingSpace,
   useRoute,
   useRouteQuery,
-  useRouter
+  useRouter,
+  useLoadPreview
 } from '@ownclouders/web-pkg'
 import { onBeforeRouteLeave } from 'vue-router'
 import { useTask } from 'vue-concurrency'
@@ -205,8 +208,6 @@ import {
 import { extractDomSelector } from '@ownclouders/web-client'
 import { storeToRefs } from 'pinia'
 
-const visibilityObserver = new VisibilityObserver()
-
 type Tag = {
   id: string
   label: string
@@ -254,7 +255,7 @@ export default defineComponent({
     const { getMatchingSpace } = useGetMatchingSpace()
 
     const resourcesStore = useResourcesStore()
-    const { initResourceList, clearResourceList, updateResourceField } = resourcesStore
+    const { initResourceList, clearResourceList } = resourcesStore
     const { totalResourcesCount } = storeToRefs(resourcesStore)
 
     const configStore = useConfigStore()
@@ -265,6 +266,7 @@ export default defineComponent({
     const doUseScope = useRouteQuery('useScope')
 
     const resourcesView = useResourcesViewDefaults<Resource, any, any[]>()
+    const { loadPreview } = useLoadPreview(resourcesView.viewMode)
     const keyActions = useKeyboardActions()
     useKeyboardTableNavigation(keyActions, resourcesView.paginatedResources, resourcesView.viewMode)
     useKeyboardTableMouseActions(keyActions, resourcesView.viewMode)
@@ -486,8 +488,8 @@ export default defineComponent({
       resourceDomSelector,
       initResourceList,
       clearResourceList,
-      updateResourceField,
-      totalResourcesCount
+      totalResourcesCount,
+      loadPreview
     }
   },
   computed: {
@@ -537,33 +539,6 @@ export default defineComponent({
         this.scrollToResourceFromRoute(this.paginatedResources, 'files-app-bar')
       }
     }
-  },
-  beforeUnmount() {
-    visibilityObserver.disconnect()
-  },
-  methods: {
-    rowMounted(resource: Resource, component: ComponentPublicInstance<unknown>) {
-      const loadPreview = async () => {
-        const preview = await this.$previewService.loadPreview(
-          {
-            space: this.getMatchingSpace(resource),
-            resource,
-            dimensions: ImageDimension.Thumbnail
-          },
-          true
-        )
-        if (preview) {
-          this.updateResourceField({ id: resource.id, field: 'thumbnail', value: preview })
-        }
-      }
-
-      const debounced = debounce(({ unobserve }) => {
-        unobserve()
-        loadPreview()
-      }, 250)
-
-      visibilityObserver.observe(component.$el, { onEnter: debounced, onExit: debounced.cancel })
-    }
   }
 })
 </script>

packages/web-app-files/src/components/Shares/SharedWithMeSection.vue

@@ -27,7 +27,13 @@
       :sort-dir="sortDir"
       :grouping-settings="groupingSettings"
       @file-click="triggerDefaultAction"
-      @row-mounted="rowMounted"
+      @item-visible="
+        loadPreview({
+          space: getMatchingSpace($event),
+          resource: $event,
+          ignoreAlmostEmptyTxtFiles: true
+        })
+      "
       @sort="sortHandler"
     >
       <template #syncEnabled="{ resource }">
@@ -104,12 +110,10 @@ import {
   useConfigStore,
   useFileActions,
   useFileActionsToggleHideShare,
+  useLoadPreview,
   useResourcesStore
 } from '@ownclouders/web-pkg'
-import { ComponentPublicInstance, computed, defineComponent, PropType, unref } from 'vue'
-import { debounce } from 'lodash-es'
-import { ImageDimension } from '@ownclouders/web-pkg'
-import { VisibilityObserver } from '@ownclouders/web-pkg'
+import { computed, defineComponent, PropType, unref } from 'vue'
 import { SortDir, useGetMatchingSpace } from '@ownclouders/web-pkg'
 import { createLocationSpaces } from '@ownclouders/web-pkg'
 import ListInfo from '../../components/FilesList/ListInfo.vue'
@@ -121,8 +125,6 @@ import { RouteLocationNamedRaw } from 'vue-router'
 import { CreateTargetRouteOptions } from '@ownclouders/web-pkg'
 import { createFileRouteOptions } from '@ownclouders/web-pkg'
 
-const visibilityObserver = new VisibilityObserver()
-
 export default defineComponent({
   components: {
     ResourceTable,
@@ -197,6 +199,7 @@ export default defineComponent({
     const capabilityStore = useCapabilityStore()
     const configStore = useConfigStore()
     const { getMatchingSpace } = useGetMatchingSpace()
+    const { loadPreview } = useLoadPreview()
 
     const { triggerDefaultAction } = useFileActions()
     const { actions: hideShareActions } = useFileActionsToggleHideShare()
@@ -229,7 +232,8 @@ export default defineComponent({
       getMatchingSpace,
       updateResourceField,
       isExternalShare,
-      ShareTypes
+      ShareTypes,
+      loadPreview
     }
   },
 
@@ -254,35 +258,7 @@ export default defineComponent({
       return this.items.slice(0, this.showMoreToggleCount)
     }
   },
-  beforeUnmount() {
-    visibilityObserver.disconnect()
-  },
   methods: {
-    rowMounted(resource: IncomingShareResource, component: ComponentPublicInstance<unknown>) {
-      const loadPreview = async () => {
-        const preview = await this.$previewService.loadPreview(
-          {
-            space: this.getMatchingSpace(resource),
-            resource,
-            dimensions: ImageDimension.Thumbnail
-          },
-          true
-        )
-        if (preview) {
-          this.updateResourceField({ id: resource.id, field: 'thumbnail', value: preview })
-        }
-      }
-
-      const debounced = debounce(({ unobserve }) => {
-        unobserve()
-        loadPreview()
-      }, 250)
-
-      visibilityObserver.observe(component.$el, {
-        onEnter: debounced,
-        onExit: debounced.cancel
-      })
-    },
     toggleShowMore() {
       this.showMore = !this.showMore
     }

packages/web-app-files/src/components/SideBar/Details/FileDetails.vue

@@ -138,7 +138,8 @@ import {
   useConfigStore,
   useResourcesStore,
   formatDateFromJSDate,
-  useResourceContents
+  useResourceContents,
+  useLoadPreview
 } from '@ownclouders/web-pkg'
 import upperFirst from 'lodash-es/upperFirst'
 import {
@@ -147,7 +148,7 @@ import {
   isTrashResource,
   ShareTypes
 } from '@ownclouders/web-client'
-import { usePreviewService, useGetMatchingSpace } from '@ownclouders/web-pkg'
+import { useGetMatchingSpace } from '@ownclouders/web-pkg'
 import { getIndicators } from '@ownclouders/web-pkg'
 import {
   formatDateFromHTTP,
@@ -157,7 +158,6 @@ import {
 import { eventBus } from '@ownclouders/web-pkg'
 import { SideBarEventTopics } from '@ownclouders/web-pkg'
 import { Resource, SpaceResource } from '@ownclouders/web-client'
-import { useTask } from 'vue-concurrency'
 import { useGettext } from 'vue3-gettext'
 import { getSharedAncestorRoute } from '@ownclouders/web-pkg'
 import { ResourceIcon } from '@ownclouders/web-pkg'
@@ -187,6 +187,7 @@ export default defineComponent({
     const capabilityStore = useCapabilityStore()
     const { getMatchingSpace } = useGetMatchingSpace()
     const { resourceContentsText } = useResourceContents({ showSizeInformation: false })
+    const { loadPreview, previewsLoading } = useLoadPreview()
 
     const language = useGettext()
     const { $gettext, current: currentLanguage } = language
@@ -200,35 +201,12 @@ export default defineComponent({
     const versions = inject<Ref<Resource[]>>('versions')
     const space = inject<Ref<SpaceResource>>('space')
 
-    const previewService = usePreviewService()
-    const preview = ref(undefined)
+    const preview = ref<string>(undefined)
 
     const authStore = useAuthStore()
     const { publicLinkContextReady } = storeToRefs(authStore)
 
-    const isPreviewEnabled = computed(() => {
-      if (unref(resource).isFolder) {
-        return false
-      }
-      return props.previewEnabled
-    })
-    const loadPreviewTask = useTask(function* (signal, resource) {
-      if (!unref(isPreviewEnabled)) {
-        preview.value = undefined
-        return
-      }
-      preview.value = yield previewService.loadPreview({
-        space: unref(space),
-        resource,
-        dimensions: ImageDimension.Preview
-      })
-    }).restartable()
-    const isPreviewLoading = computed(() => {
-      if (!unref(isPreviewEnabled)) {
-        return false
-      }
-      return loadPreviewTask.isRunning || !loadPreviewTask.last
-    })
+    const isPreviewLoading = computed(() => props.previewEnabled && unref(previewsLoading))
 
     const sharedAncestor = computed(() => {
       return Object.values(unref(ancestorMetaData)).find(
@@ -370,10 +348,16 @@ export default defineComponent({
     }
 
     watch(
-      resource,
-      () => {
+      () => unref(resource).id,
+      async () => {
         if (unref(resource)) {
-          loadPreviewTask.perform(unref(resource))
+          preview.value = await loadPreview({
+            space: unref(space),
+            resource: unref(resource),
+            dimensions: ImageDimension.Preview,
+            cancelRunning: true,
+            updateStore: false
+          })
         }
       },
       { immediate: true }