ListenerService Firebase not working with dates

Question

I've next model for my firebase entries for getting and fetching data:

struct MRecords: Hashable, Decodable {
var text: String
var date: Date
var id: String

init(text: String, date: Date, id: String) {
    self.text = text
    self.date = date
    self.id = id
}

init?(document: DocumentSnapshot) {
    guard let data = document.data() else { return nil}
    guard let text = data["text"] as? String,
    let date = data["date"] as? Date,
    let id = data["id"] as? String
    
    else { return nil }
    
    self.text = text
    self.date = date
    self.id = id
}

init?(document: QueryDocumentSnapshot) {
    let data = document.data()
    guard let text = data["text"] as? String,
    let date = data["date"] as? Date,
    let id = data["id"] as? String
    
    else { return nil }
    
    self.text = text
    self.date = date
    self.id = id
}

func hash(into hasher: inout Hasher) {
    hasher.combine(id)
}

static func == (lhs: MRecords, rhs: MRecords) -> Bool {
    return lhs.id == rhs.id
}

func contains(filter: String?) -> Bool {
    guard let filter = filter else { return true }
    if filter.isEmpty { return true }
    let lowercasedFilter = filter.lowercased()
    return text.lowercased().contains(lowercasedFilter)
}

}

And I'm using Listener to fetch data:

 func recordsObserve(records: [MRecords], completion: @escaping (Result<[MRecords], Error>) -> Void) -> ListenerRegistration? {
        var records = records
        let recordsRef = db.collection(["users", currentUserId, "records"].joined(separator: "/"))
        let recordsListener = recordsRef.addSnapshotListener { (querySnapshot, error) in
            guard let snapshot = querySnapshot else {
                print(1)
                completion(.failure(error!))
                return
            }
            
            snapshot.documentChanges.forEach { (diff) in
                guard let record = MRecords(document: diff.document) else { return }
                switch diff.type {
                case .added:
                    guard !records.contains(record) else { return }
                    records.append(record)
                case .modified:
                    guard let index = records.firstIndex(of: record) else { return }
                    records[index] = record
                case .removed:
                    guard let index = records.firstIndex(of: record) else { return }
                    records.remove(at: index)
                }
            }
            
            completion(.success(records))
        }
        
        return recordsListener
    }

In my ViewController I'm using next code to get data into array:

waitingRecordsListener = ListenerService.shared.recordsObserve(records: records, completion: { (result) in
    switch result {
    case .success(let records):
        self.records = records
        self.tableView.reloadData()
    case .failure(let error):
        print(1)
    }
})

}

But it doesn't works! If I change in my model date property type from Date to String, it begin to work. How I can make it work with Date type, not only string?

Answer 1

Thats because Firebase has not a Date Type. You have to store it as Firebase Timestamp and to calculate and convert it into a date format. The same applies if you want store date values into firebase. However it is better to use the firebase function Timestamp to store data into firebase.