Swift 3: How to retry Firebase upload on failure - swift

Question

I'm initializing some data in Firebase that I will use to track a user's activity. I need to make sure this data is written to Firebase so I'm wondering what the best practice is for ensuring a critical upload was successful?
static func createUserActivityCounts(uid: String) {
DispatchQueue.global(qos: .background).asyncAfter(deadline: .now() + .seconds(5)) {
let databaseReference = Database.database().reference()
let userCounts: [String: Any] = ["posts": 0,
"comments": 0,
"likes": 0]
databaseReference.child("userActivity").child(uid).child("counts").setValue(userCounts) { (error, ref) -> Void in
if error != nil {
print(error!.localizedDescription)
}
}
}
}

Answer 1

I think the best way to resolve this issue is to check if the value exists whenever you attempt to query a critical upload. If the value isn't there then you initialize it. Here is the function I wrote to handle this.
private func getUserActivityCounts() {
if let uid = Auth.auth().currentUser?.uid {
userRef.child("userActivity").child(uid).child("counts").observeSingleEvent(of: .value, with: { snap in
if !snap.exists() {
// create user counts
if let uid = Auth.auth().currentUser?.uid {
DatabaseFunctions.createUserActivityCounts(uid: uid)
}
}
if let counts = snap.value as? [String: Any] {
if let numberOfLikes = counts["likes"] as? Int, let commentCount = counts["comments"] as? Int, let postCount = counts["posts"] as? Int {
DispatchQueue.main.async {
self.headerRef.postCount.text = String(postCount)
self.headerRef.commentCount.text = String(commentCount)
self.headerRef.likeCount.text = String(numberOfLikes)
self.collectionView.reloadData()
}
self.numberOfUserPosts = postCount
self.commentCount = commentCount
self.likeCount = numberOfLikes
}
}
})
}
}