ios - Rich Notification in swift. Image not show in notification -

i make rich notification show image in notification whenever send simple message notification. last 2 day trying show image in notification not done. please me this.

thank in advance

this code.

in notification service extension

override func didreceive(_ request: unnotificationrequest, withcontenthandler contenthandler: @escaping (unnotificationcontent) -> void) {         self.contenthandler = contenthandler         bestattemptcontent = (request.content.mutablecopy() as? unmutablenotificationcontent)          // custom data notification payload         if let data = request.content.userinfo["data"] as? [string: string] {             // grab attachment             if let urlstring = data["attachment-url"], let fileurl = url(string: urlstring) {                 // download attachment                 urlsession.shared.downloadtask(with: fileurl) { (location, response, error) in                     if let location = location {                         // move temporary file remove .tmp extension                         let tmpdirectory = nstemporarydirectory()                         let tmpfile = "file://".appending(tmpdirectory).appending(fileurl.lastpathcomponent)                         let tmpurl = url(string: tmpfile)!                         try! filemanager.default.moveitem(at: location, to: tmpurl)                          // add attachment notification content                         if let attachment = try? unnotificationattachment(identifier: "", url: tmpurl) {                             self.bestattemptcontent?.attachments = [attachment]                         }                     }                     // serve notification content                     self.contenthandler!(self.bestattemptcontent!)                     }.resume()             }         }      } 

this notification structure

{  "aps" : {     "alert" : {         "title" : "push remote rich notifications",         "subtitle" : "ios 10 - new api",         "body" : "media image rich notification"         },     "mutable-content" : 1,     "category" : "imageidentifier"     },     "data" : {       "attachment-url": "https://raw.githubusercontent.com/sweefties/ios10-newapi-usernotifications-example/master/source/ios10-newapi-usernotifications-example.jpg"     } }