How to show image in UNNotificationServiceExtension?

Question

I added the UNNotificationServiceExtension to the application, I successfully get the data, and I load the image that comes in the data to push notification, but I can not display this image in the push notification window. Please tell me how it can be fixed?

override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
        self.contentHandler = contentHandler
        bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)

        if let bestAttemptContent = bestAttemptContent {
            // Modify the notification content here...
            bestAttemptContent.title = "Apple [modified]"
            bestAttemptContent.body = "Xcode"
            contentHandler(bestAttemptContent)

            let attachmentStorage = AttachmentStorage()

            if let imagePath = request.content.userInfo["image"] as? String {
                guard let url = URL(string: imagePath) else {
                    contentHandler(bestAttemptContent)
                    return
                }
                debugPrint("url", url)
                attachmentStorage.store(url: url) { (localURL, error) in
                    if let localURL = localURL {
                        debugPrint("path", localURL)
                        do {
                            let attachment = try UNNotificationAttachment.init(identifier: "image", url: localURL, options: nil)
                            bestAttemptContent.attachments = [attachment]
                            debugPrint("bestAttemptContent.attachments", bestAttemptContent.attachments, bestAttemptContent.attachments.count)
                            contentHandler(bestAttemptContent)
                            return
                        } catch {
                            contentHandler(bestAttemptContent)
                            return
                        }
                    }
                }
            }


            contentHandler(bestAttemptContent)
        }
    }

class AttachmentStorage {

    func store(url: URL, completion: ((URL?, Error?) -> ())?) {
        // obtain path to temporary file
        let filename = ProcessInfo.processInfo.globallyUniqueString
        let path = URL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent("\(filename).jpeg")

        // fetch attachment
        let task = URLSession.shared.dataTask(with: url) { (data, response, error) in
            do {
                let _ = try data?.write(to: path)
                completion?(path, error)
            } catch {
                debugPrint(error.localizedDescription)
                completion?(nil, error)
            }
        }
        task.resume()
    }

}

Logs

"bestAttemptContent.attachments" [<UNNotificationAttachment: 0x14dd626c0; identifier: image, family: Image, URL: file:///private/var/mobile/Containers/Data/PluginKitPlugin/1F13F774-B6CA-4567-9EF0-EA61C9A1F2A0/tmp/23A8E7EC-29FB-4C36-893D-5B0DCFB711B2-13808-000002A699FBF67B.jpeg, type: public.jpeg, options: <UNImageNotificationAttachmentOptions: 0x14dd5afd0>>] 1

I added this code. And even if you remove contentHandler sometimes you get duplicates or there were no images

let request = UNNotificationRequest.init(identifier: "image", content: bestAttemptContent, trigger: nil)
UNUserNotificationCenter.current().add(request) { (error) in
                                // handle error
                            }

Answer 1

I made this and it works for me

  override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
        self.contentHandler = contentHandler
        bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)

        if let bestAttemptContent = bestAttemptContent {
            // Modify the notification content here...
            if let imagePath = request.content.userInfo["image"] as? String {
                guard let url = URL(string: imagePath) else {
                    contentHandler(bestAttemptContent)
                    return
                }
                guard let imageData = NSData(contentsOf: url) else {
                    contentHandler(bestAttemptContent)
                    return
                }
                guard let attachment = UNNotificationAttachment.create(imageFileIdentifier: "image.jpg", data: imageData, options: nil) else {
                    print("error in UNNotificationAttachment.create()")
                    contentHandler(bestAttemptContent)
                    return
                }
                bestAttemptContent.attachments = [ attachment ]
            }
            contentHandler(bestAttemptContent)
        }
    }


extension UNNotificationAttachment {

    /// Save the image to disk
    static func create(imageFileIdentifier: String, data: NSData, options: [NSObject : AnyObject]?) -> UNNotificationAttachment? {
        let fileManager = FileManager.default
        let tmpSubFolderName = ProcessInfo.processInfo.globallyUniqueString
        guard let tmpSubFolderURL = NSURL(fileURLWithPath: NSTemporaryDirectory()).appendingPathComponent(tmpSubFolderName, isDirectory: true) else { return nil }

        do {
            try fileManager.createDirectory(at: tmpSubFolderURL, withIntermediateDirectories: true, attributes: nil)
            let fileURL = tmpSubFolderURL.appendingPathComponent(imageFileIdentifier)
            try data.write(to: fileURL, options: [])
            let imageAttachment = try UNNotificationAttachment(identifier: imageFileIdentifier, url: fileURL, options: options)
            return imageAttachment
        } catch let error {
            print("error \(error)")
        }

        return nil
    }

}