更新數據時 Swift Firebase 'FIRInvalidArgumentException'

Question

簡而言之，我正在使用圖像選擇器將圖像上傳到 firebase 存儲並將圖像 ID 保存到 firestore 中的文檔中。 圖片已成功上傳，但在嘗試將數據保存到文檔時出現錯誤：'FIRInvalidArgumentException'，原因：'Unsupported type: __SwiftValue'

為什么會這樣？

調用上傳圖片，然后保存到文檔：

ImagePickerView(currentEventID: self.liveEventID, configuration: self.pickerConfig) { imagesData in
   print("PICKER DONE: \(imagesData)")
   var eventImages: [EventImage] = []
   for imageData in imagesData {
      let imageUUID = UUID().uuidString
      self.isvm.uploadImage(currentEventID: self.liveEventID, imageUUID: imageUUID, selectedImagesData: imageData) { imageURL in
                        eventImages.append(EventImage(id: imageUUID, url: imageURL, voteCount: 1))
                        
         if eventImages.count == imagesData.count {
            print("LOOP DONE: \(eventImages)")
               self.isvm.saveImagesToEvent(currentEventID: self.liveEventID, eventImages: eventImages) { isSavedToEvent in
                  if isSavedToEvent {
                     print("SAVED IMAGES SUCCESSFULLY")
                     self.isReloadingImages = true
                                    self.isvm.getUpdatedEventPhotos(currentEventID: self.liveEventID) { liveEvent in
                     self.liveEvent = liveEvent
                     if !self.liveEvent.isEmpty {
                        self.liveEventID = self.liveEvent[0].id
                        self.isReloadingImages = false
                    }
                 }
               }
            }
         }
      }
   }
}

錯誤發生的地方：

    public func saveImagesToEvent(currentEventID: String, eventImages: [EventImage], completion: @escaping (_ isSavedToEvent: Bool) -> Void) {
        self.eventsDataCollection.document(currentEventID).updateData([
            "eventImages" : FieldValue.arrayUnion(eventImages)
        ]) { error in
            if let error = error {
                print("ERROR SAVING URLS TO EVENT: \(error)")
                completion(false)
            }
        }
        completion(true)
    }

數據model：

struct EventModel: Identifiable, Codable {
    var id: String
    var isLive: Bool
    var coors: [Coor]
    var eventCenterCoorFormatted: [Double]
    var hostTitle: String
    var eventName: String
    var eventDescription: String
    var isEventPrivate: Bool
    var eventGuestsJoined: [String]
    var eventEndDate: String
    var eventImages: [EventImage]
    
    private enum CodingKeys: String, CodingKey {
        case id
        case isLive
        case coors
        case eventCenterCoorFormatted
        case hostTitle
        case eventName
        case eventDescription
        case isEventPrivate
        case eventGuestsJoined
        case eventEndDate
        case eventImages
    }
}

struct Coor: Identifiable, Codable {
    var id = UUID()
    var coorDoubles: [Double]
    
    private enum CodingKeys: String, CodingKey {
        case coorDoubles
    }
}

struct EventImage: Identifiable, Codable {
    var id = UUID().uuidString
    var url: String
    var voteCount: Int
    
    private enum eventImage: String, CodingKey {
        case id
        case imageURL
        case voteCount
    }
}

請注意：錯誤前的最后一個打印語句是：“Loop done:”並且它成功獲取了所有 EventImage 類型的 eventImage。

Answer 1

該錯誤是由於嘗試在您的saveImagesToEvent function 中將自定義 Swift object 保存到 Firestore 引起的：

"eventImages": FieldValue.arrayUnion(eventImages)

您需要先對EventImage對象進行編碼，然后再嘗試將它們存儲在 Firestore 中。 您的EventImage結構已經符合Codable ，但 Firestore 的設置/更新數據方法不會自動對您的數據進行編碼。

要解決此問題，請確保您已在項目中包含 Firestore swift 擴展：

pod 'FirebaseFirestoreSwift'

現在您可以使用Firestore.Encoder在將數據發送到 Firestore 之前對其進行編碼：

val encodedEventImages = eventImages.map { Firestore.Encoder().encode($0) }

self.eventsDataCollection.document(currentEventID).updateData([
            "eventImages" : FieldValue.arrayUnion(encodedEventImages)
        ]) { error in
...

如果您想以自定義 Swift object 的形式讀取 Firestore 文檔中的數據，您需要按照 Firestore 文檔中的示例對其進行解碼：

docRef.getDocument { (document, error) in
    // Construct a Result type to encapsulate deserialization errors or
    // successful deserialization. Note that if there is no error thrown
    // the value may still be `nil`, indicating a successful deserialization
    // of a value that does not exist.
    //
    // There are thus three cases to handle, which Swift lets us describe
    // nicely with built-in Result types:
    //
    //      Result
    //        /\
    //   Error  Optional<City>
    //               /\
    //            Nil  City
    let result = Result {
      try document?.data(as: City.self)
    }
    switch result {
    case .success(let city):
        if let city = city {
            // A `City` value was successfully initialized from the DocumentSnapshot.
            print("City: \(city)")
        } else {
            // A nil value was successfully initialized from the DocumentSnapshot,
            // or the DocumentSnapshot was nil.
            print("Document does not exist")
        }
    case .failure(let error):
        // A `City` value could not be initialized from the DocumentSnapshot.
        print("Error decoding city: \(error)")
    }
}