How can I use local copy of MongoDB Synced Realm database while completely offline? - react-native

Question

I am using MongoDB Realm Sync on my React Native app. When I start my app online and later disconnect internet, my realm works fine. I can see my data and also I can write data which syncs with server when I go back online. But when I start my app completely offline, my app does not show any data. From what I understand, realm is suppose to read local database and return data even when the app starts from complete offline. Isn't it ? How can I access my data when I start my app offline ? Below is my code I've used to sync with server.
const config = {
schema: [sessionSchema],
sync: {
user,
partitionValue: 'Test',
},
};
try {
Realm.open(config)
.then((openedRealm) => {
if (canceled) {
openedRealm.close();
return;
}
realmRef.current = openedRealm;
const syncSessions = openedRealm.objects('session');
openedRealm.addListener('change', () => {
setSessions([...syncSessions]);
});
setSessions([...syncSessions]);
}
} catch (e) {
console.log('ERROR', e);
}

Answer 1

const OpenRealmBehaviorConfiguration = {
type: "openImmediately",
}
const configuration = {
schema: [UserSchema],
sync: {
user: app.currentUser,
partitionValue: "user_1",
// Add this two lines below
newRealmFileBehavior: OpenRealmBehaviorConfiguration,
existingRealmFileBehavior: OpenRealmBehaviorConfiguration,
}
}

Answer 2

I found an answer for similar question here: https://developer.mongodb.com/community/forums/t/open-synced-local-database-when-completely-offline/11169/2
You can do something like:
async function getRealm() {
const app = new Realm.App("your-app-id");
if (app.currentUser) {
// A user had already logged in - open the Realm synchronously
return new Realm(getConfig(app.currentUser));
}
// We don't have a user - login a user and open the realm async
const user = await app.logIn(Realm.Credentials.anonymous());
return await Realm.open(getConfig(user));
}
function getConfig(user) {
return {
sync: {
user,
partitionValue: "my-partition"
}
};
}