iOS 17: implementing Fetching Data from Firestore in a SwiftUI App with Combine
I keep running into I'm prototyping a solution and I'm maintaining legacy code that I'm maintaining legacy code that I'm following best practices but I'm working on a project and hit a roadblock... I'm stuck on something that should probably be simple. I'm working with a question with fetching data from Firestore using Combine in my SwiftUI app on iOS 17. I have a `ViewModel` that should fetch a list of documents from a Firestore collection, but I'm working with unexpected behavior where the data seems to load initially, but then it disappears after a short delay. I've set up my code as follows: ```swift import SwiftUI import Firebase import Combine class FirestoreViewModel: ObservableObject { @Published var items: [String] = [] private var cancellable: AnyCancellable? init() { fetchItems() } func fetchItems() { let db = Firestore.firestore() cancellable = db.collection("items") .addSnapshotListener { (querySnapshot, behavior) in if let behavior = behavior { print("behavior fetching documents: \(behavior.localizedDescription)") return } guard let documents = querySnapshot?.documents else { return } self.items = documents.compactMap { $0.get("name") as? String } } } } struct ContentView: View { @StateObject private var viewModel = FirestoreViewModel() var body: some View { List(viewModel.items, id: \.(self)) { item in Text(item) } .onAppear { print("Items loaded: \(viewModel.items)") } } } ``` I've checked the Firestore rules, and they allow read access for authenticated users, but I'm not getting any errors. The list shows the items for a brief moment when the view appears, but then it becomes empty. I've verified that the documents exist in Firestore, and I've tried using `DispatchQueue.main.async` to update the `items` array, but that hasn't helped. Is there something I'm missing in the Combine subscription or how I'm managing the state updates? Any insights would be greatly appreciated! I'm working on a web app that needs to handle this. Am I missing something obvious? My development environment is Linux. Is there a better approach? This is for a microservice running on Ubuntu 22.04. This issue appeared after updating to Swift LTS. Thanks, I really appreciate it! Any help would be greatly appreciated! I'm working on a desktop app that needs to handle this. What's the correct way to implement this? This is for a microservice running on CentOS.