写下这段代码，运行并在notificationService类上设置断点，然后一旦通知登陆到应用程序上，它就会登陆这个类，只需将您的通知服务类替换为以下代码并运行代码，希望它能解决您的问题。
作为参考，你也可以看到这个链接
https://medium.com/gits-apps-insight/processing-notification-data-using-notification-service-extension-6a2b5ea2da17

import UserNotifications

class NotificationService: UNNotificationServiceExtension {

    var contentHandler: ((UNNotificationContent) -> Void)?
    var bestAttemptContent: UNMutableNotificationContent?

    override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
        self.contentHandler = contentHandler
        debugPrint(request.content)
        bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)
        
        if let bestAttemptContent = bestAttemptContent {
            // Modify the notification content here...
            bestAttemptContent.title = "\(bestAttemptContent.title )"
            if let attachment = request.attachment{
                bestAttemptContent.attachments = [attachment]
            }
            
            contentHandler(bestAttemptContent)
        }
        
    }
    
    override func serviceExtensionTimeWillExpire() {
        // Called just before the extension will be terminated by the system.
        // Use this as an opportunity to deliver your "best attempt" at modified content, otherwise the original push payload will be used.
        if let contentHandler = contentHandler, let bestAttemptContent =  bestAttemptContent {
            contentHandler(bestAttemptContent)
        }
    }

}

extension UNNotificationRequest {
    var attachment: UNNotificationAttachment? {
        
//        guard let fcmOptions = content.userInfo["fcm_options"] as? [String:Any] else {return nil}
        
        guard let attachmentURL = content.userInfo["image"] as? String, let imageData = try? Data(contentsOf: URL(string: attachmentURL)!) else {
            return nil
        }
        return try? UNNotificationAttachment(data: imageData, options: nil)
    }
}

extension UNNotificationAttachment {

    convenience init(data: Data, options: [NSObject: AnyObject]?) throws {
        let fileManager = FileManager.default
        let temporaryFolderName = ProcessInfo.processInfo.globallyUniqueString
        let temporaryFolderURL = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(temporaryFolderName, isDirectory: true)

        try fileManager.createDirectory(at: temporaryFolderURL, withIntermediateDirectories: true, attributes: nil)
        let imageFileIdentifier = UUID().uuidString + ".jpg"
        let fileURL = temporaryFolderURL.appendingPathComponent(imageFileIdentifier)
        try data.write(to: fileURL)
        try self.init(identifier: imageFileIdentifier, url: fileURL, options: options)
    }
}

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