Cloud Firestore unable to retrieve document or field - ios

I've used the sample code provided by the Firebase Documentation and it prints out the error message. I have no clue if the issue is within the code or within the structure of the database, as there are also sub-collections. In this case, I am trying to retrieve the "Home Title" field, however I heard that that's not possible (I may be wrong), so I'm trying to retrieve the "Sample Wedding" document, to no avail. This is my very first time programming a project in Swift and also using Firestore.
Here's my code:
let db = Firestore.firestore()
let docRef = db.collection("Weddings").document("Sample Wedding")
docRef.getDocument { (document, error) in
if let document = document, document.exists {
let dataDescription = document.data().map(String.init(describing:)) ?? "nil"
print("Document data: \(dataDescription)")
} else {
print("Document does not exist")
}
Here's my database structure:
]

You can try it like this
let db = Firestore.firestore()
db.collection("Weddings").document("Sample Wedding").getDocument {
(documentSnapshot, err) in
if let err = err {
print("Error getting documents: \(err)")
} else {
print("Document data: \(documentSnapshot)")
if let title = documentSnapshot.get("Home Title") as? String {
print(title)
}
}
}

Related

How to read the current users profile document in Firestore

I am working on my first IOS app using Firestore. I am successfully retrieving all user documents or a specific document with a document name from the "users" collection. But as soon as I want to query the currentUsers documents I have trouble. I need the data for a user profile viewController.
I can query a specific document and print it with this code:
func loadUserData() {
let userDocumentRef = Firestore.firestore().collection("users").document(
"6tIzsXgbOMDIFpdgR18i")
userDocumentRef.getDocument { (document, error) in
if let document = document, document.exists {
let userData = document.data().map(String.init(describing: )) ?? "nil"
print("Document data: \(userData)")
} else {
print("document does not exist")
}
}
}
But as soon as I try to get the currentUsers document with this code, then I get the error that "document does not exist":
func currentUserData() {
let userID : String = (Auth.auth().currentUser?.uid)!
let userRef = Firestore.firestore().collection("users").document(userID)
userRef.getDocument { (document, error) in
if let document = document, document.exists {
let userData = document.data().map(String.init(describing: )) ?? "nil"
print("Document data: \(userData)")
} else {
print("document does not exist")
}
}
}
Here is a screenshot of the users collection in Firestore.
Screenshot of Firestore users collection
I just simply cannot figure out what I am doing wrong, so any help is appreciated.
It seems like there is an issue when mapping the document. Here is how you can map data from Firestore to Swift:
struct UserProfile: Codable, Identifiable {
#DocumentID var id: String?
var userId: String
var firstName: String
// ... other attributes
}
func currentUserData() {
// Note: this is unsafe, please use an auth state change listener instead
// Also, please try to avoid using force unwrap - your app will crash if the attribute is nil
let userID : String = (Auth.auth().currentUser?.uid)!
let userRef = Firestore.firestore().collection("users").document(userID)
userRef.getDocument { (document, error) in
if let document = document, document.exists {
let userData = document.data(as: UserProfile.self)
print("Document data: \(userData)")
} else {
print("document does not exist")
}
}
}
Here is how to set up an auth state change listener: https://firebase.google.com/docs/auth/ios/start#listen_for_authentication_state

Load data from Firebase once

I am using Firebase as my backend service & fetching data using the SnapshotListener ( which keep listening for any data changes ). I want to remove that listener (only run and fetch data on first load).
private func loadShops(_ category: String) {
db.collection(category).addSnapshotListener { snapshot, error in
guard error == nil else {
print(error!.localizedDescription)
return
}
if let docs = snapshot?.documents {
for doc in docs {
self.shops = []
let shopData = doc.data()
var newShop = Shop()
newShop.shopName = shopData["name"] as? String ?? "Empty Name"
self.shops.append(newShop)
self.shops.shuffle()
}
self.shopsView.tableView.reloadData()
}
}
}
Based on the API example above - I'm assuming you are using the Firestore API and not the older Firebase.
If its firestore, you could just use query fetch instead of using a snapshot listener.
Refer to https://firebase.google.com/docs/firestore/query-data/queries#execute_a_query
private func loadShops(_ category: String) {
db.collection(category).getDocuments() { (querySnapshot, err) in
if let err = err {
print("Error getting documents: \(err)")
} else if let querySnapshot = querySnapshot {
for document in querySnapshot.documents {
print("\(document.documentID) => \(document.data())")
// do the conversion to model object.
}
}
}
Using the snapshot listener is only if you want to continue monitoring the cloud for new documents. It is also costly as per the pricing documentation.

Retrieve Firestore collection data - Error -Unexpectedly found nil while implicitly unwrapping an Optional value

I have been working on Firestore for retrieving data, when I tried to get data from collection->document id-> field. refer the below screen shot, I need to check companyCode matches with user entered companyCode.text
I tried with below code, need to check whether the user entered companyCodeLabel.text matches document "companyCode" and also get documentId. Can anyone suggest how to solve this?
guard let code = companyCodeLabel.text else { return }
let docRef = db.collection("Company").whereField("companyCode", isEqualTo: code).limit(to: 1)
docRef.getDocuments { (querysnapshot, error) in
if error != nil {
print("Document Error: ", error!)
} else {
if let doc = querysnapshot?.documents, !doc.isEmpty {
print("Document is present.")
}
}
}
Even tried to print the field value in collection but still have crash and same error nil
self.db.collection("Company").getDocuments { (snapshot, err) in
if let err = err {
print("Error getting documents: \(err)")
} else {
for document in snapshot!.documents {
let docId = document.documentID
let compCode = document.get("companyCode") as! String
let compName = document.get("companyName") as! String
print(docId, compCode, compName)
}
}
}
I tried to call in wrong db, I was trying var db = Firestore!,
The correct solutions is
Firestore.firestore().collection("Company").getDocuments { (snapshot, err) in
if let err = err {
print("Error getting documents: \(err)")
} else {
for document in snapshot!.documents {
let docId = document.documentID
let compCode = document.get("companyCode") as! String
let compName = document.get("companyName") as! String
print(docId, compCode, compName)
}
}

SwiftUI - assign Firbase Database output to Data Model

im new to swift and Firebase. And im trying to understand it.
I have a Cloud Firestore DB, where i store some user data like username and email. Now i want the output of the given User assign to my UserData Model for easy use. i really dont know how to achiev this.
These are my two Files:
User.swift
import SwiftUI
import Firebase
import FirebaseFirestore
struct User {
var username : String
var email : String
}
GetData.swift
let docRef = db.collection("users").document(Auth.auth().currentUser?.uid)
docRef.getDocument { (document, error) in
if let document = document, document.exists {
let dataDescription = document.data().map(String.init(describing:)) ?? "nil"
print("Document data: \(dataDescription)")
} else {
print("Document does not exist")
}
}
The Variable dataDescription is givin me a dictonaryArray, with all the needed values. And now i need to assign that Dictonary to my User.swift struct.
best regards!
fYI: Firebase Printscreen
I'd recommend using Codable where you can. I'm using the CodableFirebase Cocoapod to help with Firebase parsing. Below is an example how to use this:
let docRef = db.collection("users").document(Auth.auth().currentUser?.uid)
docRef.getDocument { (document, error) in
guard let value = document.value, value as? NSNull == nil else {
return
}
do {
let newValue = try self.decoder.decode(User.self, from: value)
///New value created here
} catch let error {
print(error)
}
}
You can make this more generic by passing through a class type and having an optional instance returned:
static func item<T: Codable>(_ item: T.Type, docRef: DatabaseReference, completion: #escaping ((Result<T?, Error>)->Void)) {
docRef.getDocument { (document, error) in
guard let value = snapshot.value, value as? NSNull == nil else {
completion(.success(nil))
return
}
do {
let newValue = try self.decoder.decode(T.self, from: value)
completion(.success(newValue))
} catch let error {
completion(.failure(error))
}
}
}
try
GetData.swift
var user = User()
let docRef = db.collection("users").document(Auth.auth().currentUser?.uid)
docRef.getDocument { (document, error) in
if let document = document, document.exists {
let dataDescription = document.data().map(String.init(describing:)) ?? "nil"
print("Document data: \(dataDescription)")
user.username = document.data(["username"]) as! String
user.email= document.data(["email"]) as! String
} else {
print("Document does not exist")
}
}

How to get data from a map (object) Cloud Firestore document on Swift 4.2?

I am using Cloud Firestore as a Database for my iOS App.
I have an issue while I want to query my data when the document contains Maps (Object Type). I can not access the fields (say: firstName here) of a map (nameOnId) by having the simple query.
My code is as bellow:
let db = Firestore.firestore()
db.collection("userDetails").getDocuments() { (querySnapshot, err) in
if let err = err {
print("Error getting documents: \(err)")
} else {
for document in querySnapshot!.documents {
let results = document.data()
let result2 = results.compactMap({$0})
print("listedItems: \(document.documentID) => \(result2[0].value)") }}}
I read somewhere that in order to be able to access the values inside the map object, I need to flatten the map object, but having that does not give me access to them, the only thing that I could get into are a group of values inside the map so it only shows the keys and values for them like:
{
firstName = "John";
middleName = "British";
middleName = "Citizen";
gender = "M";
DOB = "8 December 2000 at 00:00:00 UTC+11";
}
the question is how to get access to a single value like "John" using the query?My data structure on Cloud Firestore
One way of doing it is as follows. Also its good practice to not force unwrap your querySnapshot (if the query does not exist, your app will crash!). Hope this helps!
let db = Firestore.firestore()
db.collection("userDetails").getDocuments() { (querySnapshot, err) in
if let err = err {
print("Error getting documents: \(err)")
} else if let querySnapshot = querySnapshot {
for document in querySnapshot.documents {
let results = document.data()
if let idData = results["nameOnID"] as? [String: Any] {
let firstName = idData["firstName"] as? String ?? ""
print(firstName)
}
}
}
}

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