In my iOS app, I'm using Firebase Transactions to update scoreboards based on user-generated data to avoid mistakes with concurrent updates. I save data at three points:
when the user presses 'Sign Out'
when the user force quits the app (not working yet due to timeout issue)
when the day changes while the app is running
Below is the transaction code:
func saveDataToFirebase(signUserOut: Bool)
{
let countyRef = Database.database().reference().child("countyleaderboard")
countyRef.child(self.userCounty).runTransactionBlock({ (currentData: MutableData) in
var value = currentData.value as? Float
if value == nil
{
value = Float(0.00)
}
currentData.value = value! + self.currentSessionAlt
return TransactionResult.success(withValue: currentData)
}, andCompletionBlock: {
error, commited, snap in
if commited && signUserOut
{
do
{
print("transaction complete")
try Auth.auth().signOut()
}
catch let logoutError
{
print(logoutError)
}
}
})
}
The code reaches the sign out method, but the database is not being updated. I ran the code separately, without including user sign out and the transaction completes fine.
Why does the transaction not actually complete before signing the user out? And is there a way to fix this?
Related
I am struggling to understand why my event listener that I initialize on a document is not being triggered whenever I update the document within the app in a different UIViewController. If I update it manually in Google firebase console, the listener event gets triggered successfully. I am 100% updating the correct document too because I see it get updated when I update it in the app. What I am trying to accomplish is have a running listener on the current user that is logged in and all of their fields so i can just use 1 global singleton variable throughout my app and it will always be up to date with their most current fields (name, last name, profile pic, bio, etc.). One thing I noticed is when i use setData instead of updateData, the listener event gets triggered. For some reason it doesn't with updateData. But i don't want to use setData because it will wipe all the other fields as if it is a new doc. Is there something else I should be doing?
Below is the code that initializes the Listener at the very beginning of the app after the user logs in.
static func InitalizeWhistleListener() {
let currentUser = Auth.auth().currentUser?.uid
let userDocRef = Firestore.firestore().collection("users").document(currentUser!)
WhistleListener.shared.listener = userDocRef.addSnapshotListener { documentSnapshot, error in
guard let document = documentSnapshot else {
print("Error fetching document: \(error!)")
return
}
guard let data = document.data() else {
print("Document data was empty.")
return
}
print("INSIDE LISTENER")
}
}
Below is the code that update's this same document in a different view controller whenever the user updates their profile pic
func uploadProfilePicture(_ image: UIImage) {
guard let uid = currentUser!.UID else { return }
let filePath = "user/\(uid).jpg"
let storageRef = Storage.storage().reference().child(filePath)
guard let imageData = image.jpegData(compressionQuality: 0.75) else { return }
storageRef.putData(imageData) { metadata, error in
if error == nil && metadata != nil {
self.userProfileDoc!.updateData([
"profilePicURL": filePath
]) { err in
if let err = err {
print("Error updating document: \(err)")
} else {
print("Document successfully updated")
}
}
}
}
}
You can use set data with merge true it doesn't wipe any other property only merge to specific one that you declared as like I am only update the name of the user without wiping the age or address
db.collection("User")
.document(id)
.setData(["name":"Zeeshan"],merge: true)
The answer is pretty obvious (and sad at the same time). I was constantly updating the filepath to be the user's UID therefore, it would always be the same and the snapshot wouldn't recognize a difference in the update. It had been some time since I had looked at this code so i forgot this is what it was doing. I was looking past this and simply thinking an update (no matter if it was different from the last or not) would trigger an event. That is not the case! So what I did was append an additional UUID to the user's UID so that it changed.
I have a strange bug that is occurring only on few user iPhones, details below -
The app consumes a universal framework (developed by ourself) to save accessToken and refreshToken after successful login to the Keychain. We are using Locksmith to achieve the functionality - Save, load data and delete when the user is logged out.
Everytime when the app is killed and launched or applicationWillEnterForeground, the tokens are refreshed with the help of a service call and are saved to keychain again. When the refreshToken expires (this token is valid for one month), user is notified that the app has not been used for a long time and he is logged out.
The actual problem is here that for only few users, the refresh mechanism fails even when they are using the app daily (i.e. not before completion of one month of the refreshToken). After verification with backend team, the refresh service is always up so I suspect the Locksmith loadDataForUserAccount but unable to reproduce the issue. Also, may users do NOT face the problem. Everything works normally as expected.
Can someone help me move further how to identify the cause?
Below is the code to refresh the accessToken and refreshToken
** Refresh token call From the App when app enters foreground or killed and launched**
if let mySession = ServiceLayer.sharedInstance.session {
mySession.refresh { result in
switch result {
case .failure(.authenticationFailure):
if isBackgroundFetch {
print("👤⚠️ Session refresh failed, user is now logged out.")
self.myService.logoutCurrentUser()
// Logout Current user
mySession.invalidate()
self.showLoginUI()
}
else {
// user accessToken is invalid but provide access to QR
// on the home screen. disable all other actions except logout button
self.showHomeScreen()
}
default:
mySession.getAccessToken { result in
switch result {
case let .success(value):
print("Access Token from App Delegate \(value)")
myAccessToken = value
case let .failure(error):
print("❌ Failed to fetch AccessToken: \(error)")
}
}
}
}
}
From the framework where the refresh mechanism is implemented
public func refresh(_ completion: #escaping (MyResult<String, MyError>) -> (Void)) {
guard isValid else {
completion(.failure(.invalidSession))
return
}
getRefreshToken { result in
switch result {
case let .success(refreshToken):
// Get new tokens.
ServiceClient.requestJSON(ServiceRequest.refreshToken(refreshToken: refreshToken)) { result in
switch result {
case let .success(dictionary):
var newAccessToken: String?
var newRefreshToken: String?
for (key, value) in dictionary {
if key as! String == "access_token" {
newAccessToken = value as? String
}
if key as! String == "refresh_token" {
newRefreshToken = value as? String
}
}
guard newAccessToken != nil && newRefreshToken != nil else {
completion(.failure(.general))
return
}
print("Renewed session tokens.")
do {
try Locksmith.updateData(data: [MySession.accessTokenKeychainKey: newAccessToken!, MySession.refreshTokenKeychainKey: newRefreshToken!],
forUserAccount: MySession.myKeychainAccount)
}
catch {
completion(.failure(.general))
}
completion(.success(newAccessToken!))
case let .failure(error):
if error == MyError.authenticationFailure {
print(“Session refresh failed due to authentication error; invalidating session.")
self.invalidate()
}
completion(.failure(error))
}
}
case let .failure(error):
completion(.failure(error))
}
}
}
The app is likely being launched in the background while the device is locked (for app refresh or other background mode you've configured). Protected data (including Keychain) is not necessarily available at that time. You can check UIApplication.isProtectedDataAvailable to check if it's available, and you can reduce the protection of the item to kSecAttrAccessibleAfterFirstUnlock in order to have background access more reliably (though not 100% promised, even in that mode). Locksmith calls this AfterFirstUnlock.
I execute an API call in Firebase for retrieving the user profile information and storing it in a ViewController member variable.
The API is declared as a static function inside a class MyApi:
// Get User Profile
static func getUserProfile(byID userId:String,response:#escaping (_ result:[User]?,_ error:Error?)->()) {
// check ID is valid
guard userId.length > 0 else {
print("Error retrieving Creator data: invalid user id provided")
response(nil,ApiErrors.invalidParameters)
return
}
// retrieve profile
let profilesNode = Database.database().reference().child(MyAPI.profilesNodeKey)
profilesNode.child(userId).observe(.value, with: { (snapshot) in
// check if a valid data structure is returned
guard var dictionary = snapshot.value as? [String:AnyObject] else {
print("Get User Profile API: cannot find request")
response([],nil)
return
}
// data mapping
dictionary["key"] = userId as AnyObject
guard let user = User(data:dictionary) else {
print("Get User Profile API: error mapping User profile data")
response(nil,ApiErrors.mappingError)
return
}
response([user], nil)
}) { (error) in
response(nil,ApiErrors.FirebaseError(description: error.localizedDescription))
}
}
and I call it like that:
MyAPI.getUserProfile(byID: creatorId) { (profiles, error) in
guard let profiles = profiles, profiles.count > 0 else {
Utility.showErrorBanner(message: "Error retrieving Creator profile")
print("Error retrieving creator profile ID:[\(creatorId)] \(String(describing: error?.localizedDescription))")
return
}
self.currentProfile = profiles.first!
}
The ViewController is called in Modal mode so it should be deallocated every time I exit the screen.
Problem: a huge chunk of memory get allocated when I enter the screen, but it doesn't get freed up when I leave it. I'm sure about this because the problem doesn't appear if I remove the line self.currentProfile = profiles.first! (obviously)
How can I avoid this from happening?
NOTE: currentProfile is of type User, which was used to be a struct. I made it a class so I could use a weak reference for storing the information:
weak var currentCreator: User? {
didSet {
updateView()
}
}
but the problem still persists.
You are adding an observer:
profilesNode.child(userId).observe(...)
But you never remove it. As long as that observe is still added, it will hold on to memory from the entire set of results, and continually retrieve new updates. It's a really bad practice not to remove your observers.
If you want to read data just a single time, there is a different API for that using observeSingleEvent.
In my iOS/Swift/Firebase app, I am trying to access the "isNewUser" parameter after a user successfully signs in via email/password so that I can pop a window to compel them to reset their password from the temporary one initially assigned upon user creation.
Any insights would be appreciated. Thanks.
The .isNewUser Bool is available from the FirebaseAuth AdditionalUserInfo class.
Here is the link. In order to utilize this code, please see a demo sign in function I wrote below.
Auth.auth().signIn(with: credential) { (result, error) in
if let error = error {
print("Error: \(error)");
return;
}
// Fetch the user's info
guard let uid = result?.user.uid else {return}
// Safely unwrap the boolean value rather than forcing it with "!" which could crash your app if a nil value is found
guard let newUserStatus = result?.additionalUserInfo?.isNewUser else {return}
// Test the value
print("\nIs new user? \(newUserStatus)\n")
if newUserStatus == true {
// Provide your alert prompt
}
else{
// Transition view to continue into the app
}
}
I’m using Realm Object Server for a simple test project and I’m facing problems synchronizing ROS connection setup and follow up usage of the realm object to access the database.
In viewDidLoad I’m calling connectROS function to initialize realmRos object/connection:
var realmRos: Realm!
override func viewDidLoad() {
connectROS()
if(FBSDKAccessToken.current() != nil){
// logged in
getFBUserData()
}else{
// not logged in
print("didLoad, FB user not logged in")
}
}
func connectROS() {
let username = "realm-admin"
let password = "*********"
SyncUser.logIn(with: .usernamePassword(username: username, password: password, register: false), server: URL(string: "http://146.185.154.***:9080")!)
{ user, error in
print("ROS: checking user credentials")
if let user = user {
print("ROS: user credentials OK")
DispatchQueue.main.async {
// Opening a remote Realm
print("ROS: entering dispatch Q main async")
let realmURL = URL(string: "realm://146.185.154.***:9080/~/***book_test1")!
let config = Realm.Configuration(syncConfiguration: SyncConfiguration(user: user, realmURL: realmURL))
self.realmRos = try! Realm(configuration: config)
// Any changes made to this Realm will be synced across all devices!
}
} else if let error = error {
// handle error
print("ROS: user check FAIL")
fatalError(String(describing: error))
}
}
}
In viewDidLoad function next step is to get FB logged user (in this case I’m using FB authentication). After the logged FB user is fetched, the application perform check is that FB user is new user for my application and my proprietary ROS User’s table.
func checkForExistingProfile(user: User) -> Bool {
var userThatExist: User?
do {
try self.realmRos.write() {
userThatExist = self.realmRos.object(ofType: User.self, forPrimaryKey: user.userName)
}
} catch let error as NSError {
print("ROS is not connected")
print(error.localizedDescription)
}
if userThatExist != nil {
return true
} else {
return false
}
}
At this point checkForExistingProfile usually (not always) crashes at try self.realmRos.write() which happens to be nil.
I think the problem comes from the synchronization between connectROS execution (which is asynchrony) and checkForExistingProfile which execution comes before connectROS completion.
Since you didn't show how checkForExistingProfile() is called after viewDidLoad() this is conjecture, but based on everything else you described it's the likely cause.
What you need to do is not call checkForExistingProfile() until the sync user has logged in and your self.realmRos variable has been initialized. Cocoa Touch does nothing to automatically synchronize code written using an asynchronous pattern (like logIn(), which returns immediately but reports its actual completion state in a callback), so you need to manually ensure that whatever logIn() is supposed to do has been done before you call any additional code that depends on its completion.