InvalidFirebaseData during Sign Up process - swift

Question

Currently, I am using a combination of Firebase authentication, database, and storage for my sign up process.
#objc func handleSignUp() {
guard let email = emailTextField.text else { return }
guard let password = passwordTextField.text else { return }
guard let fullName = fullNameTextField.text else { return }
guard let username = usernameTextField.text else { return }
Auth.auth().createUser(withEmail: email, password: password) { (user, error) in
//handle error
if let error = error {
print("Failed to create user with error", error.localizedDescription)
return
}
//set profile image
guard let profileImage = self.plusPhotoButton.imageView?.image else { return }
//upload data
guard let uploadData = profileImage.jpegData(compressionQuality: 0.3) else { return }
//place image in firbase storage
let filename = NSUUID().uuidString
let storage = Storage.storage()
let storageReference = storage.reference()
let imagesReference = storageReference.child("profile_images")
let uploadReference = imagesReference.child(filename)
uploadReference.putData(uploadData, metadata: nil) { (metadata, error) in
//handle error
if let error = error {
print("Failed to upload image to Firebase Storage with error", error.localizedDescription)
}
//profile image url
let profileImageURL = uploadReference.downloadURL
//user id
let uid = user?.user.uid
let dictionaryValues = ["name": fullName, "username": username, "profileImageURL": profileImageURL]
let values = [uid: dictionaryValues]
//save user info to database
Database.database().reference().child("users").updateChildValues(values) { (error, ref) in
print("Successfully created user and saved information to database")
}
}
}
This should be the code, which should be working fine.
However, xCode is giving me this error:
Heterogeneous collection literal could only be inferred to '[String : Any]'; add explicit type annotation if this is intentional
and is advising me to change
let dictionaryValues = ["name": fullName, "username": username, "profileImageURL": profileImageURL]
to
let dictionaryValues = ["name": fullName, "username": username, "profileImageURL": profileImageURL] as [String : Any]
As a result, I can compile and run the project.
However, when I press the sign-up button and therefore run the given function, the console is showing this error:
2019-09-30 19:15:13.049986+0200 5iveli0ns[965:28839] [] nw_connection_receive_internal_block_invoke [C2] Receive reply failed with error "Operation canceled"
and in the end I receive a Runtime Exception:
*** Terminating app due to uncaught exception 'InvalidFirebaseData', reason: '(updateChildValues:withCompletionBlock:) Cannot store object of type __SwiftValue at profileImageURL. Can only store objects of type NSNumber, NSString, NSDictionary, and NSArray.'
Is this an xCode 11 / Firebase 5.x.x related issue?

Answer 1

Generally speaking, Dictionaries infer their structure from the data they contain. So for example
let dict = [
"name": "Leroy",
"fav_food": "Pizza"
]
is a [String: String] Dictionary
Likewise
let dict = [
"name": "Leroy"
"age": 25
]
is a [String: Int] Dictionary.
What you have is
let dict = [
"name": "Leroy",
"username": "some username"
"profileImageUrl": URL //oops, not a string, its a URL!
]
When Dictionary values are consistent, they can be defined [String: String]. However, when the value types will vary, they are [String: Any]
The other issue is that Firebase doesn't support the URL type, so even if you used a Dictionary of [String: Any], Firebase will complain - as shown by the error.
The fix is easy - just use the path, which is a string of the url
if let url = uploadReference.downloadURL {
let path = url
let dict = [
"name": "Leroy",
"username": "some username",
"path": path //it's a string
]
//write dict to Firebase
}

Answer 2

COnvert
let profileImageURL = uploadReference.downloadURL
to String then feed it into the dictionaryValues array.
I hope that helps