手動クライアントリセットデータリカバリ - Node.js SDK

const DogSchema = {
  name: "Dog",
  properties: {
    name: "string",
    age: "int?",
    lastUpdated: "int",
  },
};

const config = {
  schema: [DogSchema],
  sync: {
    user: app.currentUser,
    partitionValue: "MyPartitionValue",
    clientReset: {
      mode: "manual",
    },
    error: handleSyncError, // callback function defined later
  },
};

const LastSyncedSchema = {
  name: "LastSynced",
  properties: {
    realmTracked: "string",
    timestamp: "int?",
  },
  primaryKey: "realmTracked",
};
const lastSyncedConfig = { schema: [LastSyncedSchema] };
const lastSyncedRealm = await Realm.open(lastSyncedConfig);
lastSyncedRealm.write(() => {
  lastSyncedRealm.create("LastSynced", {
    realmTracked: "Dog",
  });
});

// Listens for changes to the Dogs collection
realm.objects("Dog").addListener(async () => {
  // only update LastSynced if sync session is connected
  // and all local changes are synced
  if (realm.syncSession.isConnected()) {
    await realm.syncSession.uploadAllLocalChanges();
    lastSyncedRealm.write(() => {
      lastSyncedRealm.create("LastSynced", {
        realmTracked: "Dog",
        timestamp: Date.now(),
      });
    });
  }
});

async function handleSyncError(_session, error) {
  if (error.name === "ClientReset") {
    const realmPath = realm.path; // realm.path will not be accessible after realm.close()
    realm.close(); // you must close all realms before proceeding
    // pass your realm app instance and realm path to initiateClientReset()
    Realm.App.Sync.initiateClientReset(app, realmPath);
    // Redownload the realm
    realm = await Realm.open(config);
    const oldRealm = await Realm.open(error.config);
    const lastSyncedTime = lastSyncedRealm.objectForPrimaryKey(
      "LastSynced",
      "Dog"
    ).timestamp;
    const unsyncedDogs = oldRealm
      .objects("Dog")
      .filtered(`lastUpdated > ${lastSyncedTime}`);
    // add unsynced dogs to synced realm
    realm.write(() => {
      unsyncedDogs.forEach((dog) => {
        realm.create("Dog", dog, "modified");
      });
    });
    // delete dogs from synced realm that were deleted locally
    const syncedDogs = realm
      .objects("Dog")
      .filtered(`lastUpdated <= ${lastSyncedTime}`);
    realm.write(() => {
      syncedDogs.forEach((dog) => {
        if (!oldRealm.objectForPrimaryKey("Dog", dog._id)) {
          realm.delete(dog);
        }
      });
    });
    // make sure everything syncs and close old realm
    await realm.syncSession.uploadAllLocalChanges();
    oldRealm.close();
  } else {
    console.log(`Received error ${error.message}`);
  }
}