Firebase -How to loop through snapshot.hasChild("...") - ios

Question

My database is laid out like below
users
|
#--uidABC
|
|---phone:"[phone]"
|
|---followers
|
|----uid123
| |---timeStamp:111222
|
|----uid456
| |---timeStamp:777999
I use .observeSingleEvent to check to see if uidABC exists and if it does I want to check to see if there is a child named followers under that path.
I can use snapshot.hasChild("followers") to see if it's available and if it is how can I loop through all the children underneath snapshot.hasChild("...")?
I use the code below but it's looping through the wrong snapshot. It using the top level one when it should use whatever DataSnapshot is under followers
let ref = Database...child("users").child(uidABC)
ref.observeSingleEvent(of: .value, with: { (snapshot) in
if !snapshot.exists() {
// this user doesn't exist
return
}
if !snapshot.hasChild("followers") {
// this user exists but has no followers
return
}
// this user exists and has followers now loop through them
for uid in snapshot.children {
let snapshot = uid as! DataSnapshot
if let dict = snapshot.value as? [String:Any] {
let timeStamp = dict["timeStamp"] as? Double
// eg. check for a specific timeStamp
}
}
})

Answer 1

I got the answer from here and here
let ref = Database...child("users").child(uidABC)
ref.observeSingleEvent(of: .value, with: { (snapshot) in
if !snapshot.exists() {
// this user doesn't exist
return
}
if !snapshot.hasChild("followers") {
// this user exists but has no followers
return
}
// this user exists and has followers now loop through them
let childSnapshot = snapshot.childSnapshot(forPath: "followers") {
for child in childSnapshot.children {
let snap = child as! DataSnapshot
let uid = snap.key
if let dict = snap.value as? [String: Any] {
let timeStamp = dict["timeStamp"] as? Double ?? 0
// eg. check for a specific timeStamp
}
}
})

Answer 2

Use child:
// this user exists and has followers now loop through them
for uid in snapshot.childSnapshot("followers") {
guard let snapshot = uid as! DataSnapshot else {
// Followers error
}
if let dict = snapshot.value as? [String:Any] {
let timeStamp = dict["timeStamp"] as? Double
// eg. check for a specific timeStamp
}
}
You can find more here:
Iterate over snapshot children in Firebase