realmTask[1000:40858] Sync: Connection[1]: Connected to endpoint '127.0.0.1:9080'
realmTask[1000:40858] Sync: Connection[1]: Writing failed: End of input
realmTask[1000:40858] Sync: Connection[1]: Connection closed due to error

func setupRealm() {
    // Log in existing user with username and password
    let username = "abcdefg"
    let password = "1234"

    SyncUser.logIn(with: .usernamePassword(username: username, password: password, register: false), server: URL(string: "http://127.0.0.1:9080")!) { user, error in
        guard let user = user else {
            fatalError(String(describing: error))
        }

        DispatchQueue.main.async {
            // Open Realm
            let configuration = Realm.Configuration(
                syncConfiguration: SyncConfiguration(user: user, realmURL: URL(string: "realm://127.0.0.1:9080/~/realmtasks")!)
            )
            self.realm = try! Realm(configuration: configuration)

            // Show initial tasks
            func updateList() {
                if self.items.realm == nil, let list = self.realm.objects(TaskList.self).first {
                    self.items = list.items
                }
                self.tableView.reloadData()
            }
            updateList()

            // Notify us when Realm changes
            self.notificationToken = self.realm.observe { _,_ in
                updateList()
            }
        }
    }
}

deinit {
    notificationToken?.invalidate()
}