Firebase Retrieving Data in Swift - ios

I'm trying to retrieve specific data from just the currently logged in user. My data in my database looks like this:
For example, I want to just grab the full_name and save it in a variable userName. Below is what I'm using to grab my data
ref.queryOrderedByChild("full_name").queryEqualToValue("userIdentifier").observeSingleEventOfType(.ChildAdded, withBlock: { snapshot in
print(snapshot.value)
// let userName = snapshot.value["full_name"] as! String
})
Unfortunately, this is what my console prints.
I would appreciate any help :) Thank you!

It gives you that warning message indexOn because you are doing a query.
you should define the keys you will be indexing on via the .indexOn
rule in your Security and Firebase Rules. While you are allowed to
create these queries ad-hoc on the client, you will see greatly
improved performance when using .indexOn
As you know the name you are looking for you can directly go to that node, without a query.
let ref:FIRDatabaseReference! // your ref ie. root.child("users").child("stephenwarren001#yahoo.com")
// only need to fetch once so use single event
ref.observeSingleEventOfType(.Value, withBlock: { snapshot in
if !snapshot.exists() { return }
//print(snapshot)
if let userName = snapshot.value["full_name"] as? String {
print(userName)
}
if let email = snapshot.value["email"] as? String {
print(email)
}
// can also use
// snapshot.childSnapshotForPath("full_name").value as! String
})

Swift 4
let ref = Database.database().reference(withPath: "user")
ref.observeSingleEvent(of: .value, with: { snapshot in
if !snapshot.exists() { return }
print(snapshot) // Its print all values including Snap (User)
print(snapshot.value!)
let username = snapshot.childSnapshot(forPath: "full_name").value
print(username!)
})

{
"rules": {
"tbl_name": {
".indexOn": ["field_name1", "field_name2"]
},
".read": true,
".write": true
}
}
You can apply indexOn on any field. Add this json in rules security and rules tab.
Hope this works for you. :)

It retrieves logged in user data:
let ref = FIRDatabase.database().reference(fromURL: "DATABASE_URl")
let userID = FIRAuth.auth()?.currentUser?.uid
let usersRef = ref.child("users").child(userID!).observeSingleEvent(of: .value, with: { (snapshot) in
print(snapshot)

let ref = Database.database().reference().child("users/stephenwarren001#yahoo.com")
ref.observeSingleEvent(of: .value, with: { (snap : DataSnapshot) in
print("\(String(describing: snap.value))")
}) { (err: Error) in
print("\(err.localizedDescription)")
}

var refDatabase = DatabaseReference()
refDatabase = Database.database().reference().child("users");
let refUserIdChild = refDatabase.child("stephenwarren001#yahoo.com")
refUserIdChild.observeSingleEvent(of: .value, with: { snapshot in
if !snapshot.exists() { return }
print(snapshot) // Its print all values including Snap (User)
print(snapshot.value!)
if let tempDic : Dictionary = snapshot.value as? Dictionary<String,Any>
{
if let userName = tempDic["full_name"] as? String {
self.tfName.text = userName
}
if let email = tempDic["email"] as? String {
self.tfEmail.text = email
}
}
})

Related

how to delete child record from firebase in swift?

I wanted to delete this record in firebase, where i don't have the name of the key. so, I don't know how to do it. can anybody help me with this?
The code for getting array is as follows
var databaseRefer : DatabaseReference!
let userID = Auth.auth().currentUser?.uid
databaseRefer = Database.database().reference(withPath: userID!)
databaseRefer.observeSingleEvent(of: .value, with: { snapshot in
if !snapshot.exists() { return }
if snapshot.value is NSNull {
print("not found")
} else {
for child in snapshot.children {
let snap = child as! DataSnapshot
print(dict)
dict.forEach { item in
print(item.value)
}
}
}
})
https://firebase.google.com/docs/database/ios/read-and-write
"The simplest way to delete data is to call removeValue on a reference to the location of that data."

Swift, iOS: How do I extract data from my firebase database?

This is my firebase database.
I wish to go through my database to grab each ticket's value such as "ignore", "Peter rabbit....", "Incredibles 2....", etc.
Currently I am extracting data like this:
ref = Database.database().reference()
let uid = Auth.auth().currentUser?.uid
ref?.child("users").child(uid!).observe(.childAdded, with: { (snapshot) in
if let userDict = snapshot.value as? [String:String] {
self.movieNameFromTickets.append(myValue)
}
})
But I feel that it isn't a good way to extract data because if I have another structure like tickets, it might print out the wrong information.
What would be a better way to extract my tickets' values?
Thanks :)
Try this :
Database
.database()
.reference()
.child("Users")
.child(Auth.auth().currentUser!.uid)
.child("Advertisements")
.queryOrderedByKey()
.observeSingleEvent(of: .value, with: { snapshot in
guard let dict = snapshot.value as? [String:Any] else {
print("Error")
return
}
// get value from dict here .
})

How to parse a firebase real time database

How I can parse firebase realtime database?
So far my code is:
var ref: DatabaseReference!
ref = Database.database().reference()
ref.child("data").observe(.childAdded) { (snapshot) in
print("snapshot = \(snapshot)")
}
I can not enter the condition.
print("url = \(ref.url)")
url = "https://gdenamaz.firebaseio.com"
this variant don't work too
var ref: DatabaseReference!
ref = Database.database().reference().child("data")
ref.observeSingleEvent(of: .value) { (snapshot) in
for data in snapshot.children {
print("data = \(data)")
}
}
To reference the official docs -
refHandle = postRef.observe(DataEventType.value, with: { (snapshot) in
let postDict = snapshot.value as? [String : AnyObject] ?? [:]
// ...
})
You want to be looking for the snapshot.value not snapshot.children
A further example
let userID = Auth.auth().currentUser?.uid
ref.child("users").child(userID!).observeSingleEvent(of: .value, with: { (snapshot) in
// Get user value
let value = snapshot.value as? NSDictionary
let username = value?["username"] as? String ?? ""
let user = User(username: username)
// ...
}) { (error) in
print(error.localizedDescription)
}
also, .childAdded will only trigger when a child is added. IE, nothing will happen until you actually change something in that node reference.

Firebase retrieve data below auto ID In Swift

I'm in trouble in retrieving data from Firebase.
I'd like to read all contactName data in JSON under auto ID , then append to UIPickerView.
Here is my JSON tree (used childByAutoId())
And Here is my Swift Code
dbRef = Database.database().reference()
dbRef.child("user").child("contacts").queryOrdered(byChild: "contactName").observeSingleEvent(of: .value, with: {(snapshot) in
for snap in snapshot.children {
let userSnap = snap as! DataSnapshot
let contactName = userSnap.value as? String
self.pickOption.append("\(contactName)")
}
})
But the result shows me all nil data... looks like this.
How Can I fix it..?
I solved myself!
But first of all, I decided not to use UIPickerView.
And what I wanna do is to add data below auto ID.
I'm not sure this is good algorithm for solving this problem, But Anyway, I made it :)
dbRef.child("user/contacts/").observe(.value, with: {(snapshot) in
if let result = snapshot.children.allObjects as? [DataSnapshot] {
for child in result {
let orderID = child.key as String //get autoID
self.dbRef.child("user/contacts/\(orderID)/contactName").observe(.value, with: { (snapshot) in
if let nameDB = snapshot.value as? String {
if self.debtorName == nameDB {
self.dbRef.child("user/contacts/\(orderID)").updateChildValues(data)
}
}
})
}
}
})

How to retrieve data from current User in Firebase using Swift?

I am trying to get current users firstname from firebase using swift code. Below is my JSON file and swift code. But it's not retrieving first name. Please suggest
Json:
Swift code:
if FIRAuth.auth()?.currentUser != nil{
let queryRef = FIRDatabase.database().reference().child("expatsappmembers")
let userID : String = (FIRAuth.auth()?.currentUser?.uid)!
print("Current user ID is" + userID)
queryRef.child("uid").child(userID).observeSingleEvent(of: .value, with: {(snapshot) in
print(snapshot.value)
let userName = (snapshot.value as! NSDictionary)["firstname"] as! String
print(userName)
})
}
It is slightly different to get a value from Firebase in Swift 3
the proper way to do it is:
ref.child("expatsappmembers").queryOrderedByKey().observeSingleEvent(of: .value, with: { (snapshot) in
// Get user value
let value = snapshot.value as? NSDictionary
let firstName = value?["firstname"] as? String
// ...
}) { (error) in
print(error.localizedDescription)
}

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