feat: Speed up app display

We used to init search at app initilization. However, we noticed that
this can be time consuming and slow down the app openening. Thus, we
prefer to make the user wait for an extra few seconds for the first
search, to init the search at this moment, rather than waiting at each
app opening.  Note we previously have added the index persistence
feature, in order to speed up this initialization.

src/App.js

@@ -73,7 +73,6 @@ import LauncherView from '/screens/konnectors/LauncherView'
 import { makeImportantFilesAvailableOfflineInBackground } from '/app/domain/io.cozy.files/importantFiles'
 import { useOfflineReplicationOnRealtime } from '/app/domain/offline/hooks/useOfflineReplicationOnRealtime'
 import { useShareFiles } from '/app/domain/osReceive/services/shareFilesService'
-import { initSearchEngine } from '/app/domain/search/search'
 import { ClouderyOffer } from '/app/view/IAP/ClouderyOffer'
 import { useDimensions } from '/libs/dimensions'
 import { configureFileLogger } from '/app/domain/logger/fileLogger'
@@ -136,12 +135,6 @@ const App = ({ setClient }) => {
   useOfflineDebugUniversalLinks(client)
   usePerformancesUniversalLinks(client)
 
-  useEffect(() => {
-    if (client) {
-      initSearchEngine(client)
-    }
-  }, [client])
-
   const {
     LauncherDialog,
     canDisplayLauncher,

src/app/domain/search/search.ts

@@ -12,20 +12,41 @@ import { getData, storeData } from '/libs/localStore/storage'
 const log = Minilog('📱🗂️ Search')
 
 let searchEngine: SearchEngine | undefined = undefined
+let searchInitPromise: Promise<SearchEngine> | null = null
 
 const storage: StorageInterface = {
   storeData: storeData,
   getData: getData
 }
 
-export const initSearchEngine = (client: CozyClient): void => {
+export const initSearchEngine = (client: CozyClient): Promise<SearchEngine> => {
   log.debug('Init SearchEngine')
-  searchEngine = new SearchEngine(client, storage, CozyClientPerformanceApi)
+
+  if (!searchInitPromise) {
+    // Use promise to handle parallel init
+    searchInitPromise = (async (): Promise<SearchEngine> => {
+      searchEngine = new SearchEngine(
+        client,
+        storage,
+        CozyClientPerformanceApi,
+        { shouldInit: false } // Do the init manually to ensure all the indexes are ready
+      )
+      await searchEngine.init() // Once the init is done, we can safely search
+      searchInitPromise = null
+      return searchEngine
+    })()
+  }
+  return searchInitPromise
 }
 
-export const search = (query: string, options: SearchOptions): unknown => {
+export const search = async (
+  client: CozyClient,
+  query: string,
+  options: SearchOptions
+): Promise<unknown> => {
   log.debug('Search for', query)
-  if (!searchEngine) return undefined
-
+  if (!searchEngine) {
+    searchEngine = await initSearchEngine(client)
+  }
   return searchEngine.search(query, options)
 }

src/libs/intents/localMethods.ts

@@ -97,8 +97,15 @@ export const backToHome = (): Promise<null> => {
   return Promise.resolve(null)
 }
 
-const search = (query: string, options: SearchOptions): unknown => {
-  return doSearch(query, options)
+const search = async (
+  client: CozyClient | undefined,
+  query: string,
+  options: SearchOptions
+): Promise<unknown> => {
+  if (!client) {
+    throw new Error('search should not be called with undefined client')
+  }
+  return doSearch(client, query, options)
 }
 
 const isAvailable = (featureName: string): Promise<boolean> => {
@@ -227,7 +234,7 @@ interface CustomMethods {
   storeSharedMemory: (key: string, value: SharedMemoryData) => Promise<void>
   removeSharedMemory: (key: string) => Promise<void>
   setColorScheme: (colorScheme: string | undefined) => Promise<void>
-  search: (query: string, options: SearchOptions) => unknown
+  search: (query: string, options: SearchOptions) => Promise<unknown>
 }
 
 type WithOptions<T> = {
@@ -420,7 +427,7 @@ export const localMethods = (
       _options: PostMeMessageOptions,
       query: string,
       options: SearchOptions
-    ) => search(query, options),
+    ) => search(client, query, options),
     ...mergedMethods
   }
 }