From fee954bf27d7f3e24e03518a5849e8f8931b7ba1 Mon Sep 17 00:00:00 2001
From: Nolan Lawson <nolan@nolanlawson.com>
Date: Thu, 8 Feb 2018 17:51:48 -0800
Subject: [PATCH] clean up actions, implement cache-first sync strategy

---
 .../[accountId].js => _actions/accounts.js}   |  6 ++--
 .../add.js => _actions/addInstance.js}        | 12 ++++----
 .../instances.js}                             | 29 +++++++++----------
 routes/_actions/lists.js                      | 20 +++++++++++++
 routes/_actions/timeline.js                   |  3 --
 routes/_components/Nav.html                   |  7 -----
 routes/_store/observers.js                    |  6 ++--
 routes/_utils/sync.js                         | 18 ++++++++++++
 routes/accounts/[accountId].html              |  4 +--
 routes/community/_actions/community.js        | 19 ------------
 routes/community/index.html                   |  4 +--
 routes/lists/[listId].html                    |  4 ---
 routes/settings/instances/[instanceName].html |  2 +-
 routes/settings/instances/add.html            |  2 +-
 14 files changed, 69 insertions(+), 67 deletions(-)
 rename routes/{accounts/_actions/[accountId].js => _actions/accounts.js} (90%)
 rename routes/{settings/instances/_actions/add.js => _actions/addInstance.js} (90%)
 rename routes/{settings/instances/_actions/[instanceName].js => _actions/instances.js} (71%)
 create mode 100644 routes/_actions/lists.js
 create mode 100644 routes/_utils/sync.js
 delete mode 100644 routes/community/_actions/community.js

diff --git a/routes/accounts/_actions/[accountId].js b/routes/_actions/accounts.js
similarity index 90%
rename from routes/accounts/_actions/[accountId].js
rename to routes/_actions/accounts.js
index 054c44de..0414577c 100644
--- a/routes/accounts/_actions/[accountId].js
+++ b/routes/_actions/accounts.js
@@ -1,6 +1,6 @@
-import { getAccount, getRelationship } from '../../_api/user'
-import { database } from '../../_database/database'
-import { store } from '../../_store/store'
+import { getAccount, getRelationship } from '../_api/user'
+import { database } from '../_database/database'
+import { store } from '../_store/store'
 
 async function updateAccount(accountId, instanceName, accessToken) {
   let localPromise = database.getAccount(instanceName, accountId)
diff --git a/routes/settings/instances/_actions/add.js b/routes/_actions/addInstance.js
similarity index 90%
rename from routes/settings/instances/_actions/add.js
rename to routes/_actions/addInstance.js
index 064db686..6cf9d226 100644
--- a/routes/settings/instances/_actions/add.js
+++ b/routes/_actions/addInstance.js
@@ -1,10 +1,10 @@
-import { getAccessTokenFromAuthCode, registerApplication, generateAuthLink } from '../../../_api/oauth'
-import { getInstanceInfo } from '../../../_api/instance'
+import { getAccessTokenFromAuthCode, registerApplication, generateAuthLink } from '../_api/oauth'
+import { getInstanceInfo } from '../_api/instance'
 import { goto } from 'sapper/runtime.js'
-import { switchToTheme } from '../../../_utils/themeEngine'
-import { database } from '../../../_database/database'
-import { store } from '../../../_store/store'
-import { updateVerifyCredentialsForInstance } from './[instanceName]'
+import { switchToTheme } from '../_utils/themeEngine'
+import { database } from '../_database/database'
+import { store } from '../_store/store'
+import { updateVerifyCredentialsForInstance } from './instances'
 
 const REDIRECT_URI = (typeof location !== 'undefined' ?
   location.origin : 'https://pinafore.social') + '/settings/instances/add'
diff --git a/routes/settings/instances/_actions/[instanceName].js b/routes/_actions/instances.js
similarity index 71%
rename from routes/settings/instances/_actions/[instanceName].js
rename to routes/_actions/instances.js
index 8f8c6318..63dd0319 100644
--- a/routes/settings/instances/_actions/[instanceName].js
+++ b/routes/_actions/instances.js
@@ -1,10 +1,10 @@
-import { getVerifyCredentials } from '../../../_api/user'
-import { store } from '../../../_store/store'
-import { switchToTheme } from '../../../_utils/themeEngine'
-import { toast } from '../../../_utils/toast'
-import { database } from '../../../_database/database'
+import { getVerifyCredentials } from '../_api/user'
+import { store } from '../_store/store'
+import { switchToTheme } from '../_utils/themeEngine'
+import { toast } from '../_utils/toast'
+import { database } from '../_database/database'
 import { goto } from 'sapper/runtime.js'
-import pAny from 'p-any'
+import { cacheFirstUpdateAfter } from '../_utils/sync'
 
 export function changeTheme(instanceName, newTheme) {
   let instanceThemes = store.get('instanceThemes')
@@ -55,14 +55,11 @@ function setStoreVerifyCredentials(instanceName, thisVerifyCredentials) {
 
 export async function updateVerifyCredentialsForInstance(instanceName) {
   let loggedInInstances = store.get('loggedInInstances')
-  let instanceData = loggedInInstances[instanceName]
-  await pAny([
-    database.getInstanceVerifyCredentials(instanceName).then(verifyCredentials => {
-      setStoreVerifyCredentials(instanceName, verifyCredentials)
-    }),
-    getVerifyCredentials(instanceName, instanceData.access_token).then(verifyCredentials => {
-      setStoreVerifyCredentials(instanceName, verifyCredentials)
-      return database.setInstanceVerifyCredentials(instanceName, verifyCredentials)
-    })
-  ])
+  let accessToken = loggedInInstances[instanceName].access_token
+  await cacheFirstUpdateAfter(
+    () => getVerifyCredentials(instanceName, accessToken),
+    () => database.getInstanceVerifyCredentials(instanceName),
+    verifyCredentials => database.setInstanceVerifyCredentials(instanceName, verifyCredentials),
+    verifyCredentials => setStoreVerifyCredentials(instanceName, verifyCredentials)
+  )
 }
\ No newline at end of file
diff --git a/routes/_actions/lists.js b/routes/_actions/lists.js
new file mode 100644
index 00000000..da3616d3
--- /dev/null
+++ b/routes/_actions/lists.js
@@ -0,0 +1,20 @@
+import { store } from '../_store/store'
+import { database } from '../_database/database'
+import { getLists } from '../_api/lists'
+import { cacheFirstUpdateAfter } from '../_utils/sync'
+
+export async function updateLists() {
+  let instanceName = store.get('currentInstance')
+  let accessToken = store.get('accessToken')
+
+  await cacheFirstUpdateAfter(
+    () => getLists(instanceName, accessToken),
+    () => database.getLists(instanceName),
+    lists => database.setLists(instanceName, lists),
+    lists => {
+      let instanceLists = store.get('instanceLists')
+      instanceLists[instanceName] = lists
+      store.set({instanceLists: instanceLists})
+    }
+  )
+}
\ No newline at end of file
diff --git a/routes/_actions/timeline.js b/routes/_actions/timeline.js
index 79534b4b..bd69db42 100644
--- a/routes/_actions/timeline.js
+++ b/routes/_actions/timeline.js
@@ -63,9 +63,6 @@ export function initializeTimeline() {
 
 export async function setupTimeline() {
   mark('setupTimeline')
-  let timelineName = store.get('currentTimeline')
-  let instanceName = store.get('currentInstance')
-  let accessToken = store.get('accessToken')
   if (!store.get('timelineItemIds').length) {
     await fetchTimelineItemsAndPossiblyFallBack()
   }
diff --git a/routes/_components/Nav.html b/routes/_components/Nav.html
index 655bb478..0f2655ba 100644
--- a/routes/_components/Nav.html
+++ b/routes/_components/Nav.html
@@ -64,15 +64,8 @@
 <script>
   import NavItem from './NavItem'
   import { store } from '../_store/store'
-  import { fetchLists } from '../community/_actions/community'
 
   export default {
-    async oncreate() {
-      let pinnedPage = this.store.get('pinnedPage')
-      if (pinnedPage.startsWith('/lists')) {
-        await fetchLists()
-      }
-    },
     store: () => store,
     components: {
       NavItem
diff --git a/routes/_store/observers.js b/routes/_store/observers.js
index d99b1cad..478ede69 100644
--- a/routes/_store/observers.js
+++ b/routes/_store/observers.js
@@ -1,11 +1,11 @@
-import { updateVerifyCredentialsForInstance } from '../settings/instances/_actions/[instanceName]'
-import { fetchLists } from '../community/_actions/community'
+import { updateVerifyCredentialsForInstance } from '../_actions/instances'
+import { updateLists } from '../_actions/lists'
 
 export function observers(store) {
   store.observe('currentInstance', (currentInstance) => {
     if (currentInstance) {
       updateVerifyCredentialsForInstance(currentInstance)
-      fetchLists()
+      updateLists()
     }
   })
 }
\ No newline at end of file
diff --git a/routes/_utils/sync.js b/routes/_utils/sync.js
new file mode 100644
index 00000000..f426d06c
--- /dev/null
+++ b/routes/_utils/sync.js
@@ -0,0 +1,18 @@
+// Hit both the cache and the network, setting state for the cached version first,
+// then the network version (as it's assumed to be fresher). Also update the db afterwards.
+export async function cacheFirstUpdateAfter(networkFetcher, dbFetcher, dbUpdater, stateSetter) {
+  let networkPromise = networkFetcher() // kick off network request immediately
+  let dbResponse
+  try {
+    dbResponse = await dbFetcher()
+    stateSetter(dbResponse)
+  } finally {
+    let fetchAndUpdatePromise = networkPromise.then(networkResponse => {
+      /* no await */ dbUpdater(networkResponse)
+      stateSetter(networkResponse)
+    })
+    if (!dbResponse) { // no cached result available, await the network
+      await fetchAndUpdatePromise
+    }
+  }
+}
\ No newline at end of file
diff --git a/routes/accounts/[accountId].html b/routes/accounts/[accountId].html
index cbf6fa8c..977ee57a 100644
--- a/routes/accounts/[accountId].html
+++ b/routes/accounts/[accountId].html
@@ -31,9 +31,9 @@
   import { store } from '../_store/store.js'
   import HiddenFromSSR from '../_components/HiddenFromSSR'
   import DynamicPageBanner from '../_components/DynamicPageBanner.html'
-  import { updateProfileAndRelationship } from './_actions/[accountId]'
+  import { updateProfileAndRelationship } from '../_actions/accounts'
   import AccountProfile from '../_components/AccountProfile.html'
-  import { updateVerifyCredentialsForInstance } from '../settings/instances/_actions/[instanceName]'
+  import { updateVerifyCredentialsForInstance } from '../_actions/instances'
 
   export default {
     oncreate() {
diff --git a/routes/community/_actions/community.js b/routes/community/_actions/community.js
deleted file mode 100644
index 25dfbe04..00000000
--- a/routes/community/_actions/community.js
+++ /dev/null
@@ -1,19 +0,0 @@
-import { store } from '../../_store/store'
-import pAny from 'p-any'
-import { database } from '../../_database/database'
-import { getLists } from '../../_api/lists'
-
-export async function fetchLists() {
-  let instanceName = store.get('currentInstance')
-  let accessToken = store.get('accessToken')
-  let lists = await pAny([
-    getLists(instanceName, accessToken).then(lists => {
-      /* no await */ database.setLists(instanceName, lists)
-      return lists
-    }),
-    database.getLists(instanceName)
-  ])
-  let instanceLists = store.get('instanceLists')
-  instanceLists[instanceName] = lists
-  store.set({instanceLists: instanceLists})
-}
\ No newline at end of file
diff --git a/routes/community/index.html b/routes/community/index.html
index 28dbf585..459303c7 100644
--- a/routes/community/index.html
+++ b/routes/community/index.html
@@ -54,11 +54,11 @@
   import HiddenFromSSR from '../_components/HiddenFromSSR'
   import PageList from './_components/PageList.html'
   import PageListItem from './_components/PageListItem.html'
-  import { fetchLists } from './_actions/community'
+  import { updateLists } from '../_actions/lists'
 
   export default {
     async oncreate() {
-      await fetchLists()
+      await updateLists()
     },
     store: () => store,
     components: {
diff --git a/routes/lists/[listId].html b/routes/lists/[listId].html
index 38e50291..716e1f26 100644
--- a/routes/lists/[listId].html
+++ b/routes/lists/[listId].html
@@ -25,12 +25,8 @@
   import { store } from '../_store/store.js'
   import HiddenFromSSR from '../_components/HiddenFromSSR'
   import DynamicPageBanner from '../_components/DynamicPageBanner.html'
-  import { fetchLists } from '../community/_actions/community'
 
   export default {
-    async oncreate() {
-      await fetchLists()
-    },
     computed: {
       list: (params, $lists) => $lists && $lists.find(_ => _.id === params['listId']),
       listTitle: (list) => list ? list.title : ''
diff --git a/routes/settings/instances/[instanceName].html b/routes/settings/instances/[instanceName].html
index 7d7e485e..68d08f81 100644
--- a/routes/settings/instances/[instanceName].html
+++ b/routes/settings/instances/[instanceName].html
@@ -106,7 +106,7 @@
     switchToInstance,
     logOutOfInstance,
     updateVerifyCredentialsForInstance
-  } from './_actions/[instanceName]'
+  } from '../../_actions/instances'
   import { themes } from '../../_static/themes'
 
   export default {
diff --git a/routes/settings/instances/add.html b/routes/settings/instances/add.html
index bd9e62bd..451262b9 100644
--- a/routes/settings/instances/add.html
+++ b/routes/settings/instances/add.html
@@ -72,7 +72,7 @@
   import SettingsLayout from '../_components/SettingsLayout.html'
   import { store } from '../../_store/store'
   import LoadingMask from '../../_components/LoadingMask'
-  import { logInToInstance, handleOauthCode } from './_actions/add'
+  import { logInToInstance, handleOauthCode } from '../../_actions/addInstance'
   import ExternalLink from '../../_components/ExternalLink.html'
 
   export default {