Client reset w/recovery (#4711)

CHANGELOG.md

@@ -1,10 +1,9 @@
 ## vNext (TBD)
-
 ### Enhancements
 * Add support for using functions as default property values, in order to allow dynamic defaults [#5001](https://github.com/realm/realm-js/pull/5001), [#2393](https://github.com/realm/realm-js/issues/2393)
 * All fields of a `Realm.Object` treated as optional by TypeScript when constructing a new class-based model, unless specified in the second type parameter [#5000](https://github.com/realm/realm-js/pull/5000)
-* Improve performance of client reset with automatic recovery and converting top-level tables into embedded tables. ([realm/realm-core#5897](https://github.com/realm/realm-core/pull/5897))
 * If a sync client sends a message larger than 16 MB, the sync server will request a client reset. ([realm/realm-core#5209](https://github.com/realm/realm-core/issues/5209))
+* Add two new modes to client reset: `RecoverUnsyncedChanges` and `RecoverOrDiscardUnsyncedChanges`. The two modes will recover local/unsynced changes with changes from the server if possible. If not possible, `RecoverOrDiscardUnsyncedChanges` will remove the local Realm file and download a fresh file from the server. The mode `DiscardLocal` is duplicated as `DiscardUnsyncedChanges`, and `DiscardLocal` is be removed in a future version. ([#4135](https://github.com/realm/realm-js/issues/4135))
 
 ### Fixed
 * Fixed a use-after-free if the last external reference to an encrypted Realm was closed between when a client reset error was received and when the download of the new Realm began. ([realm/realm-core#5949](https://github.com/realm/realm-core/pull/5949), since v10.20.0)

docs/sync.js

@@ -37,9 +37,11 @@
 /**
  * This describes the options to configure client reset.
  * @typedef {Object} Realm.App.Sync~ClientResetConfiguration
- * @property {string} mode - Either "manual" (see also `Realm.App.Sync.initiateClientReset()`) or "discardLocal" (download a fresh copy from the server). Default is "discardLocal".
- * @property {callback(realm)|null} [onBefore] - called before sync initiates a client reset.
- * @property {callback(beforeRealm, afterRealm)|null} [onAfter] - called after client reset has been executed; `beforeRealm` and `afterRealm` are instances of the Realm before and after the client reset.
+ * @property {string} mode - Either "manual" (deprecated, see also `Realm.App.Sync.initiateClientReset()`), "discardUnsyncedChanges" (download a fresh copy from the server), "recoverUnsyncedChanges" (merged remote and local, unsynced changes), or "recoverOrDiscardUnsyncedChanges" (download a fresh copy from the server if recovery of unsynced changes is not possible)
+ * @property {callback(realm)|null} [onBefore] - called before sync initiates a client reset (only for "discardUnsyncedChanges", "recoverUnsyncedChanges" or "recoverOrDiscardUnsyncedChanges" modes).
+ * @property {callback(beforeRealm, afterRealm)|null} [onAfter] - called after client reset has been executed; `beforeRealm` and `afterRealm` are instances of the Realm before and after the client reset (only for "discardUnsyncedChanges", "recoverUnsyncedChanges" or "recoverOrDiscardUnsyncedChanges" modes).
+ * @property {callback(session, path)|null} [onFallback] - called if recovery or discard fail (only for "recoverUnsyncedChanges" or "recoverOrDiscardUnsyncedChanges" modes).
+ * @property {callback(session, path)|null} [onManual] - perform manual client reset - see also `Realm.App.Sync.initiateClientReset()` (only "manual" mode).
  * @since {10.11.0}
  */
 

integration-tests/realm-apps/with-db-flx/functions/triggerClientReset/config.json

@@ -0,0 +1,5 @@
+{
+    "name": "triggerClientReset",
+    "private": false,
+    "run_as_system": true
+}

integration-tests/realm-apps/with-db-flx/functions/triggerClientReset/source.js

@@ -0,0 +1,29 @@
+////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2022 Realm Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////
+
+/* eslint-env node */
+/* global context */
+
+exports = async function (appId, userId) {
+  return (await deleteClientFile(`__realm_sync_${appId}`, userId)) || (await deleteClientFile(`__realm_sync`, userId));
+};
+
+async function deleteClientFile(db, userId) {
+  const mongodb = context.services.get("mongodb");
+  return (await mongodb.db(db).collection("clientfiles").deleteMany({ ownerId: userId })).deletedCount > 0;
+}

integration-tests/realm-apps/with-db/functions/triggerClientReset/config.json

@@ -0,0 +1,5 @@
+{
+    "name": "triggerClientReset",
+    "private": false,
+    "run_as_system": true
+}

integration-tests/realm-apps/with-db/functions/triggerClientReset/source.js

@@ -0,0 +1,29 @@
+////////////////////////////////////////////////////////////////////////////
+//
+// Copyright 2022 Realm Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+////////////////////////////////////////////////////////////////////////////
+
+/* eslint-env node */
+/* global context */
+
+exports = async function (appId, userId) {
+  return (await deleteClientFile(`__realm_sync_${appId}`, userId)) || (await deleteClientFile(`__realm_sync`, userId));
+};
+
+async function deleteClientFile(db, userId) {
+  const mongodb = context.services.get("mongodb");
+  return (await mongodb.db(db).collection("clientfiles").deleteMany({ ownerId: userId })).deletedCount > 0;
+}

integration-tests/tests/src/tests/index.ts

@@ -38,3 +38,4 @@ import "./sync/sync-as-local";
 import "./transaction";
 import "./schema";
 import "./types";
+import "./sync/client-reset";

integration-tests/tests/src/tests/sync/asymmetric.ts

@@ -23,6 +23,7 @@ import { authenticateUserBefore, importAppBefore, openRealmBeforeEach } from "..
 
 describe.skipIf(environment.missingServer, "Asymmetric sync", function () {
   describe("Configuration and schema", function () {
+    this.timeout(20 * 1000);
     const PersonSchema: Realm.ObjectSchema = {
       name: "Person",
       asymmetric: true,