feat: Handle offline queries

When a client is started without network, e.g. from the mobile app, we
can rely on PouchDB to query the required docs and build the search
indexes.
We used to rely on replication events to make the indexing, but this is
not working of there is no network.

packages/cozy-dataproxy-lib/src/search/SearchEngine.ts

@@ -69,39 +69,24 @@ export class SearchEngine {
     if (!this.client) {
       return
     }
-    let startReplicationTime = 0,
-      endReplicationTime = 0
-    if (!this.isLocalSearch) {
-      // In case of non-local search, force the indexing for all doctypes
-      // For local search, this will be done automatically after initial replication
-      for (const doctype of SEARCHABLE_DOCTYPES) {
-        this.searchIndexes[doctype] = await this.indexDocsForSearch(
-          doctype as keyof typeof SEARCH_SCHEMA
-        )
-      }
+
+    // Create search indexes by querying docs, either locally or remotely
+    for (const doctype of SEARCHABLE_DOCTYPES) {
+      const startIndexingTime = performance.now()
+      this.searchIndexes[doctype] = await this.indexDocsForSearch(
+        doctype as keyof typeof SEARCH_SCHEMA
+      )
+      const endIndexingTime = performance.now()
+      log.debug(
+        `Indexing ${doctype} took ${(
+          endIndexingTime - startIndexingTime
+        ).toFixed(2)}`
+      )
     }
+
     if (this.isLocalSearch) {
-      this.client.on('pouchlink:doctypesync:end', async (doctype: string) => {
-        if (isSearchedDoctype(doctype)) {
-          // Index doctype after initial replication
-          this.searchIndexes[doctype] = await this.indexDocsForSearch(
-            doctype as keyof typeof SEARCH_SCHEMA
-          )
-        }
-      })
-      this.client.on('pouchlink:sync:start', () => {
-        log.debug('Started pouch replication')
-        startReplicationTime = performance.now()
-      })
-      this.client.on('pouchlink:sync:end', () => {
-        log.debug('Ended pouch replication')
-        endReplicationTime = performance.now()
-        log.debug(
-          `Replication took ${(
-            endReplicationTime - startReplicationTime
-          ).toFixed(2)}`
-        )
-      })
+      // Use replication events to have up-to-date search indexes, based on local data
+      this.indexOnReplicationEvents()
     }
 
     if (this.client.isLogged) {
@@ -113,6 +98,33 @@ export class SearchEngine {
     }
   }
 
+  indexOnReplicationEvents(): void {
+    let startReplicationTime = 0,
+      endReplicationTime = 0
+
+    this.client.on('pouchlink:doctypesync:end', async (doctype: string) => {
+      if (isSearchedDoctype(doctype)) {
+        // Index doctype after initial replication
+        this.searchIndexes[doctype] = await this.indexDocsForSearch(
+          doctype as keyof typeof SEARCH_SCHEMA
+        )
+      }
+    })
+    this.client.on('pouchlink:sync:start', () => {
+      log.debug('Started pouch replication')
+      startReplicationTime = performance.now()
+    })
+    this.client.on('pouchlink:sync:end', () => {
+      log.debug('Ended pouch replication')
+      endReplicationTime = performance.now()
+      log.debug(
+        `Replication took ${(endReplicationTime - startReplicationTime).toFixed(
+          2
+        )}`
+      )
+    })
+  }
+
   afterLogin(): void {
     // Ensure login is done before plugin register
     this.client.registerPlugin(RealtimePlugin, {})