firebase观察数据异步

Question

我正在尝试以异步方式从实时数据库中观察数据。

为此，我使用“ with with CheckedContinature”返回结果，但是我在iOS文档中看到，延续只能是“简历”一次，因此每次我更新数据库中的数据时，都会破坏我的应用程序。

我想知道我正在尝试的方法是可能的，还是还有其他方法可以解决此问题，以使该功能保持异步。

class StoreFirebase {
    private let ref = Database.database().reference()
    var driverObserver: UInt?
    var driverReference: DatabaseReference?
    
    func getDriverSingleLocation(_ uuid: String) async -> Result<StoreData, Error> {
        
        return await withCheckedContinuation { continuation in
            driverReference?.observeSingleEvent(of: .value) { (snapshot) in
                if let dictionary = snapshot.value as? StoreData {
                    continuation.resume(returning: .success(dictionary))
                } else {
                    continuation.resume(returning: .failure(HTTPError(.badRequest)))
                }
            }
        }
    }
    
    func getDriverLocation(_ uuid: String) async -> Result<StoreData, Error> {
        driverReference = ref.child("driversAvailable").child(uuid)
        
        return await withCheckedContinuation { continuation in
            var nillableContinuation: CheckedContinuation<Result<StoreData, Error>, Never>? = continuation

            driverObserver = driverReference?.observe(.value) { (snapshot) in
                if let dictionary = snapshot.value as? StoreData {
                    nillableContinuation?.resume(returning: .success(dictionary))
                    
                    
                } else {
                    nillableContinuation?.resume(returning: .failure(HTTPError(.badRequest)))
                   
                }
            }
        }
    }
}

Answer 1

thx发表评论，用异步链修复

class RealTimeDatabaseService: RealTimeDatabaseProtocol {
    private let ref = Database.database().reference()
    var driverObserver: UInt?
    var driverReference: DatabaseReference?
    
    func getDriverLocation(_ uuid: String) -> AsyncStream <Result<StoreData, Error>> {
        driverReference = ref.child("driversAvailable").child(uuid)
        
        return AsyncStream { continuation in
            driverObserver = driverReference?.observe(.value) { (snapshot) in
                if let dictionary = snapshot.value as? StoreData {
                    continuation.yield(.success(dictionary))
                } else {
                    continuation.yield(.failure(HTTPError(.badRequest)))
                    continuation.finish()
                }
            }
        }
    }

    func getDriverLocationResult() async  {
        for try await response in 'getDriverLocation'("uid") {
            switch response {
            case .success(let storeDate):
                print("completed: \(storeDate)")
            case .failure(let error):
                print("error: \(error)")
            }
        }
    }