fix(observers): refactor instance observers, minor optimizations (#730)

try to defer more work, split everything up into more functional code for easier reading

routes/_actions/lists.js

@@ -3,16 +3,17 @@ import { getLists } from '../_api/lists'
 import { cacheFirstUpdateAfter } from '../_utils/sync'
 import { database } from '../_database/database'
 
-export async function updateLists () {
-  let { currentInstance, accessToken } = store.get()
+export async function updateListsForInstance (instanceName) {
+  let { loggedInInstances } = store.get()
+  let accessToken = loggedInInstances[instanceName].access_token
 
   await cacheFirstUpdateAfter(
-    () => getLists(currentInstance, accessToken),
-    () => database.getLists(currentInstance),
-    lists => database.setLists(currentInstance, lists),
+    () => getLists(instanceName, accessToken),
+    () => database.getLists(instanceName),
+    lists => database.setLists(instanceName, lists),
     lists => {
       let { instanceLists } = store.get()
-      instanceLists[currentInstance] = lists
+      instanceLists[instanceName] = lists
       store.set({ instanceLists: instanceLists })
     }
   )

routes/_pages/community/index.html

@@ -92,13 +92,13 @@
   import HiddenFromSSR from '../../_components/HiddenFromSSR'
   import PageList from '../../_components/community/PageList.html'
   import PageListItem from '../../_components/community/PageListItem.html'
-  import { updateLists } from '../../_actions/lists'
+  import { updateListsForInstance } from '../../_actions/lists'
 
   export default {
     async oncreate () {
       let { currentInstance } = this.store.get()
       if (currentInstance) {
-        await updateLists()
+        await updateListsForInstance(currentInstance)
       }
     },
     store: () => store,

routes/_store/observers/instanceObservers.js

@@ -1,16 +1,98 @@
 import { updateInstanceInfo, updateVerifyCredentialsForInstance } from '../../_actions/instances'
-import { updateLists } from '../../_actions/lists'
+import { updateListsForInstance } from '../../_actions/lists'
 import { createStream } from '../../_actions/streaming'
 import { updatePushSubscriptionForInstance } from '../../_actions/pushSubscription'
 import { updateCustomEmojiForInstance } from '../../_actions/emoji'
 import { addStatusesOrNotifications } from '../../_actions/addStatusOrNotification'
 import { getTimeline } from '../../_api/timelines'
 import { TIMELINE_BATCH_SIZE } from '../../_static/timelines'
+import { scheduleIdleTask } from '../../_utils/scheduleIdleTask'
+import { mark, stop } from '../../_utils/marks'
+
+// stream to watch for home timeline updates and notifications
+let currentInstanceStream
+
+async function refreshInstanceDataAndStream (store, instanceName) {
+  mark(`refreshInstanceDataAndStream-${instanceName}`)
+  await doRefreshInstanceDataAndStream(store, instanceName)
+  stop(`refreshInstanceDataAndStream-${instanceName}`)
+}
+
+function currentInstanceChanged (store, instanceName) {
+  return store.get().currentInstance !== instanceName
+}
+
+async function doRefreshInstanceDataAndStream (store, instanceName) {
+  if (currentInstanceChanged(store, instanceName)) {
+    return
+  }
+
+  await refreshInstanceData(instanceName)
+
+  if (currentInstanceChanged(store, instanceName)) {
+    return
+  }
+
+  let { currentInstanceInfo } = store.get()
+  if (!currentInstanceInfo) {
+    return
+  }
+
+  stream(store, instanceName, currentInstanceInfo)
+}
+
+async function refreshInstanceData (instanceName) {
+  // these are all low-priority
+  scheduleIdleTask(() => updateVerifyCredentialsForInstance(instanceName))
+  scheduleIdleTask(() => updateCustomEmojiForInstance(instanceName))
+  scheduleIdleTask(() => updateListsForInstance(instanceName))
+  scheduleIdleTask(() => updatePushSubscriptionForInstance(instanceName))
+
+  // this is the only critical one
+  await updateInstanceInfo(instanceName)
+}
+
+function stream (store, instanceName, currentInstanceInfo) {
+  let homeTimelineItemIds = store.getForTimeline(instanceName,
+    'home', 'timelineItemIds')
+  let firstHomeTimelineItemId = homeTimelineItemIds && homeTimelineItemIds[0]
+  let notificationItemIds = store.getForTimeline(instanceName,
+    'notifications', 'timelineItemIds')
+  let firstNotificationTimelineItemId = notificationItemIds && notificationItemIds[0]
+
+  let { accessToken } = store.get()
+  let streamingApi = currentInstanceInfo.urls.streaming_api
+
+  function onOpenStream () {
+    if (currentInstanceChanged(store, instanceName)) {
+      return
+    }
+
+    /* no await */ fillGap(instanceName, accessToken, 'home', firstHomeTimelineItemId)
+    /* no await */ fillGap(instanceName, accessToken, 'notifications', firstNotificationTimelineItemId)
+  }
+
+  currentInstanceStream = createStream(streamingApi, instanceName, accessToken, 'home', onOpenStream)
+
+  if (process.env.NODE_ENV !== 'production') {
+    window.currentInstanceStream = currentInstanceStream
+  }
+}
+
+// fill in the "streaming gap" – i.e. fetch the most recent 20 items so that there isn't
+// a big gap in the timeline if you haven't looked at it in awhile
+async function fillGap (instanceName, accessToken, timelineName, firstTimelineItemId) {
+  if (!firstTimelineItemId) {
+    return
+  }
+  let newTimelineItems = await getTimeline(instanceName, accessToken,
+    timelineName, null, firstTimelineItemId, TIMELINE_BATCH_SIZE)
+  if (newTimelineItems.length) {
+    addStatusesOrNotifications(instanceName, timelineName, newTimelineItems)
+  }
+}
 
 export function instanceObservers (store) {
-  // stream to watch for home timeline updates and notifications
-  let currentInstanceStream
-
   store.observe('currentInstance', async (currentInstance) => {
     if (!process.browser) {
       return
@@ -26,64 +108,6 @@ export function instanceObservers (store) {
       return
     }
 
-    /* no await */ updateVerifyCredentialsForInstance(currentInstance)
-    /* no await */ updateCustomEmojiForInstance(currentInstance)
-    /* no await */ updateLists()
-    /* no await */ updatePushSubscriptionForInstance(currentInstance)
-    await updateInstanceInfo(currentInstance)
-
-    let currentInstanceIsUnchanged = () => {
-      let { currentInstance: newCurrentInstance } = store.get()
-      return newCurrentInstance === currentInstance
-    }
-
-    if (!currentInstanceIsUnchanged()) {
-      return
-    }
-
-    let { currentInstanceInfo } = store.get()
-    if (!currentInstanceInfo) {
-      return
-    }
-
-    let homeTimelineItemIds = store.getForTimeline(currentInstance,
-      'home', 'timelineItemIds')
-    let firstHomeTimelineItemId = homeTimelineItemIds && homeTimelineItemIds[0]
-    let notificationItemIds = store.getForTimeline(currentInstance,
-      'notifications', 'timelineItemIds')
-    let firstNotificationTimelineItemId = notificationItemIds && notificationItemIds[0]
-
-    let onOpenStream = async () => {
-      if (!currentInstanceIsUnchanged()) {
-        return
-      }
-
-      // fill in the "streaming gap" – i.e. fetch the most recent 20 items so that there isn't
-      // a big gap in the timeline if you haven't looked at it in awhile
-      async function fillGap (timelineName, firstTimelineItemId) {
-        if (!firstTimelineItemId) {
-          return
-        }
-        let newTimelineItems = await getTimeline(currentInstance, accessToken,
-          timelineName, null, firstTimelineItemId, TIMELINE_BATCH_SIZE)
-        if (newTimelineItems.length) {
-          addStatusesOrNotifications(currentInstance, timelineName, newTimelineItems)
-        }
-      }
-
-      await Promise.all([
-        fillGap('home', firstHomeTimelineItemId),
-        fillGap('notifications', firstNotificationTimelineItemId)
-      ])
-    }
-
-    let { accessToken } = store.get()
-    let streamingApi = currentInstanceInfo.urls.streaming_api
-    currentInstanceStream = createStream(streamingApi,
-      currentInstance, accessToken, 'home', onOpenStream)
-
-    if (process.env.NODE_ENV !== 'production') {
-      window.currentInstanceStream = currentInstanceStream
-    }
+    scheduleIdleTask(() => refreshInstanceDataAndStream(store, currentInstance))
   })
 }