Originally wrote my Firebase/Firestore code in a separate project and am now beginning to manually integrate that code into the main tree. The exact code snippet throws no errors in separate project but does in the main:
import Foundation
import Firebase
import FirebaseFirestore
struct Title: Codable, Equatable {
var id: Int
var type: String
var title: String
var overview: String?
var imagePath: String?
}
class Titles: ObservableObject {
#Published var content: [Title]
#Published var title: Title = Title(id: -999, type: "init", title: "...")
private var db = Firestore.firestore()
private var listenerRegistration: ListenerRegistration?
init() {
self.content = []
}
deinit {
unsubscribe()
}
func unsubscribe() {
if listenerRegistration != nil {
listenerRegistration?.remove()
listenerRegistration = nil
}
}
func subscribe(_ uid: String) {
if listenerRegistration == nil {
listenerRegistration = db.collection("Lib").document(uid).collection("userLib").addSnapshotListener { (querySnapshot, error) in
guard let documents = querySnapshot?.documents else {
print("No documents")
return
}
self.content = documents.compactMap { queryDocumentSnapshot in
// throwing: Argument passed to call that takes no arguments
// & Cannot convert value of type '()' to closure result type 'Title?'
try? queryDocumentSnapshot.data(as: Title.self)
}
}
}
}
func writeLibrary(_ uid: String) {
let titleDoc = db.collection("Lib").document(uid).collection("userLib").document(UUID().uuidString)
do {
// throwing: No exact matches in call to instance method 'setData
try titleDoc.setData(from: title.self)
print("writeLibrary() created document")
} catch {
print("Error writing from writeLirbary() \(error)")
}
}
}
As noted with the comments in above, the errors are thrown at the try? data(as: ) and try setData(from: ) methods.
Not sure if there is an issue with how Swift Package Manager imported dependancies or if I am missing an import. For example, under the imported package in Firebase master/Firestore/Swift/Source/Codable/ the DocumentSnapsot+ReadDecodable.swift is there but for some reason isn't imported.
Any community perspectives on this would be helpful.
Related
How to use downloaded URL from getData class in AsyncImage?
struct RecentItemsView: View {
var item: dataType // var's from getData class
var body: some View {
HStack(spacing: 15) {
AsyncImage(url: URL(string: item.pic), content: { image in // item.pic here
image.resizable()
}, placeholder: {
ProgressView()
})
I have full URL from downloadURL but when Im using item.pic parameter in AsyncImage I get error: (See Image)
I understand that the error contains the path to the image, which is not suitable for AsyncImage, that's why I downloaded the full URL, the question is how to use the received URL in AsyncImage?
class getData : ObservableObject {
#Published var datas = [dataType]()
init() {
let db = Firestore.firestore()
db.collection("items").getDocuments { (snap, err) in
if err != nil {
print((err?.localizedDescription)!)
return
}
for i in snap!.documents {
let id = i.documentID
let title = i.get("title") as! String
let description = i.get("description") as! String
let pic = i.get("pic") as! String
self.datas.append(dataType(id: id, title: title, description: description, pic: pic))
let storage = Storage.storage()
let storageRef = storage.reference().child("\(pic)")
storageRef.downloadURL { url, error in
if let error = error {
print("Failed to download url:", error)
return
} else {
print(url!) // Full Url- https://firebasestorage.googleapis.com:...
}
}
}
}
}
}
struct dataType : Identifiable {
var id = UUID().uuidString
var title : String
var description : String
var pic : String
}
Error:
Storage:
Firestore:
This is going to look quite a bit different from your current approach but give it a try, it will simplify your code overall.
Main differences are the use of async await and FirebaseFirestoreSwift.
I choose using async await/Concurrency because it provides a more linear approach to the code and I think resolves your issue about sharing the variable with all the objects.
This is what your ObservableObject will look like
//Keeps UI Updates on the main thread
#MainActor
//Classes and structs should always be uppercased
class GetData : ObservableObject {
#Published var datas = [DataType]()
private var task: Task<Void, Never>? = nil
init() {
task = Task{
do{
try await getData()
}catch{
//Ideally you should present this error
//to the users so they know that something has gone wrong
print(error)
}
}
}
deinit{
task?.cancel()
}
func getData() async throws {
let documentPath = "items"
let svc = FirebaseService()
//async await allows a more linear approach. You can get the images individually
var items : [DataType] = try await svc.retrieve(path: documentPath)
for (idx, item) in items.enumerated() {
//Check if your url is a full url
if !item.pic.localizedCaseInsensitiveContains("https"){
//If it isnt a full url get it from storage and replace the url
items[idx].pic = try await svc.getImageURL(imagePath: item.pic).absoluteString
//Optional update the object so you dont have to retrieve the
//The url each time.
try svc.update(path: documentPath, object: items[idx])
}
}
datas = items
}
}
and your struct should change to use #DocumentID.
//This is a much simpler solution to decoding
struct DataType : Identifiable, FirestoreProtocol {
#DocumentID var id : String?
//If you get decoding errors make these variables optional by adding a ?
var title : String
var description : String
var pic : String
}
Your Views can now be modified to use the updated variables.
#available(iOS 15.0, *)
public struct DataTypeListView: View{
#StateObject var vm: GetData = .init()
public init(){}
public var body: some View{
List(vm.datas){ data in
DataTypeView(data: data)
}
}
}
#available(iOS 15.0, *)
struct DataTypeView: View{
let data: DataType
var body: some View{
HStack{
Text(data.title)
AsyncImage(url: URL(string: data.pic), content: { phase in
switch phase{
case .success(let image):
image
.resizable()
.scaledToFit()
.frame(width: 50, height: 50)
case .failure(let error):
Image(systemName: "rectangle.fill")
.onAppear(){
print(error)
}
case .empty:
Image(systemName: "rectangle.fill")
#unknown default:
Image(systemName: "rectangle.fill")
}
})
}
}
}
The class GetData is pretty bare bones an uses the code below to actually make the calls, I like using generics to simplify code and so it can be reused by various places.
You don't have to completely understand what is going on with this now but you should, I've put a ton of comments so it should be easy.
import FirebaseStorage
import FirebaseFirestore
import FirebaseFirestoreSwift
import SwiftUI
import FirebaseAuth
struct FirebaseService{
private let storage: Storage = .storage()
private let db: Firestore = .firestore()
///Retrieves the storage URL for an image path
func getImageURL(imagePath: String?) async throws -> URL{
guard let imagePath = imagePath else {
throw AppError.unknown("Invalid Image Path")
}
typealias PostContinuation = CheckedContinuation<URL, Error>
//Converts an completion handler approach to async await/concurrency
return try await withCheckedThrowingContinuation { (continuation: PostContinuation) in
storage.reference().child(imagePath).downloadURL { url, error in
if let error = error {
continuation.resume(throwing: error)
} else if let url = url {
continuation.resume(returning: url)
} else {
continuation.resume(throwing: AppError.unknown("Error getting image url"))
}
}
}
}
///Retireves the documetns from the Firestore and returns an array of objects
func retrieve<FC>(path: String) async throws -> [FC] where FC : FirestoreProtocol{
let snapshot = try await db.collection(path).getDocuments()
return snapshot.documents.compactMap { doc in
do{
return try doc.data(as: FC.self)
}catch{
//If you get any decoding errors adjust your struct, you will
//likely need optionals
print(error)
return nil
}
}
}
///Updates the provided document into the provided path
public func update<FC : FirestoreProtocol>(path: String, object: FC) throws{
guard let id = object.id else{
throw AppError.needValidId
}
try db.collection(path).document(id).setData(from: object)
}
}
enum AppError: LocalizedError{
case unknown(String)
case needValidId
}
protocol FirestoreProtocol: Identifiable, Codable{
///Use #DocumentID from FirestoreSwift
var id: String? {get set}
}
All of this code works, if you put all this code in a .swift file it will compile and it should work with your database.
I did more trial and error and a bit of online research and this is what I came back with:
func presentWelcomeMessage() {
//Get specific document from current user
let docRef = Firestore.firestore()
.collection("users")
.whereField("uid", isEqualTo: Auth.auth().currentUser?.uid ?? "")
// Get data
docRef.getDocuments { (querySnapshot, err) in
if let err = err {
print(err.localizedDescription)
} else if querySnapshot!.documents.count != 1 {
print("More than one document or none")
} else {
let document = querySnapshot!.documents.first
let dataDescription = document?.data()
guard let firstname = dataDescription?["firstname"] else { return }
self.welcomeLabel.text = "Hey, \(firstname) welcome!"
}
}
It works, but am not sure if it is the most optimal solution.
First I should say firstname is not really the best way to store a var. I would recommend using firstName instead for readability. I also recommend getting single documents like I am, rather than using a whereField.
An important thing to note is you should create a data model like I have that can hold all of the information you get.
Here is a full structure of how I would get the data, display it, and hold it.
struct UserModel: Identifiable, Codable {
var id: String
var firstName: String
private enum CodingKeys: String, CodingKey {
case id
case firstName
}
}
import SwiftUI
import FirebaseAuth
import FirebaseFirestore
import FirebaseFirestoreSwift
class UserDataManager: ObservableObject {
private lazy var authRef = Auth.auth()
private lazy var userInfoCollection = Firestore.firestore().collection("users")
public func getCurrentUIDData(completion: #escaping (_ currentUserData: UserModel) -> Void) {
if let currentUID = self.authRef.currentUser?.uid {
self.userInfoCollection.document(currentUID).getDocument { (document, error) in
if let document = document {
if let userData = try? document.data(as: UserModel.self) {
completion(userData)
}
} else if let error = error {
print("Error getting current UID data: \(error)")
}
}
} else {
print("No current UID")
}
}
}
struct ContentView: View {
#State private var userData: UserModel? = nil
private let
var body: some View {
ZStack {
if let userData = self.userData { <-- safely unwrap data
Text("Hey, \(userData.firstName) welcome!")
}
}
.onAppear {
if self.userData == nil { <-- onAppear can call more than once
self.udm.getCurrentUIDData { userData in
self.userData = userData <-- pass data from func to view
}
}
}
}
}
Hopefully this can point you in a better direction of how you should be getting and displaying data. Let me know if you have any further questions or issues.
When I compile I get this error "The path to the document cannot be empty".
To fix this, I should add an unescaped closure.
How to add an unescaped closure to the fetchUsers () function and call the GetCorsodiLaurea () function in the closure? In such a way, the compiler will not try to execute functions asynchronously.
LoginViewModel
import SwiftUI
import Firebase
import LocalAuthentication
class LoginViewModel: ObservableObject {
#Published var email: String = ""
#Published var password: String = ""
#AppStorage("use_face_id") var useFaceID: Bool = false
#AppStorage("use_face_email") var faceIDEmail: String = ""
#AppStorage("use_face_password") var faceIDPassword: String = ""
//Log Status
#AppStorage("log_status") var logStatus: Bool = false
//MARK: Error
#Published var showError: Bool = false
#Published var errorMsg: String = ""
// MARK: Firebase Login
func loginUser(useFaceID: Bool,email: String = "",password: String = "")async throws{
let _ = try await Auth.auth().signIn(withEmail: email != "" ? email : self.email, password: password != "" ? password : self.password)
DispatchQueue.main.async {
if useFaceID && self.faceIDEmail == ""{
self.useFaceID = useFaceID
// MARK: Storing for future face ID Login
self.faceIDEmail = self.email
self.faceIDPassword = self.password
}
self.logStatus = true
}
}
//MARK: FaceID Usage
func getBioMetricStatus()->Bool{
let scanner = LAContext()
return scanner.canEvaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, error: .none)
}
// MARK: FaceID Login
func autenticationUser()async throws{
let status = try await LAContext().evaluatePolicy(.deviceOwnerAuthenticationWithBiometrics, localizedReason: "To Login Into App")
if status{
try await loginUser(useFaceID: useFaceID,email: self.faceIDEmail,password: self.faceIDPassword)
}
}
}
ProfileViewModel
import Firebase
import FirebaseDatabase
import FirebaseFirestoreSwift
import SwiftUI
class ProfileViewModel: ObservableObject {
#Published var userInfo: UserModel = .empty
#Published var userDegree: userDegreeModel = .empty
#Published var isSignedIn = false
#Published var showError: Bool = false
#Published var errorMsg: String = ""
var uid = Auth.auth().currentUser!.uid
let db = Firestore.firestore()
init() {
// listen for auth state change and set isSignedIn property accordingly
Auth.auth().addStateDidChangeListener { auth, user in
if let user = user {
print("Signed in as user \(user.uid).")
self.uid = user.uid
self.isSignedIn = true
}
else {
self.isSignedIn = false
self.userInfo.Nomeintero = ""
}
}
fetchUser() { [self] in
fetchDegrees()
}
}
func fetchUser(completion: #escaping () -> Void) {
let docRef = db.collection("users").document(uid)
docRef.getDocument { document, error in
if let error = error as NSError? {
self.errorMsg = "Error getting document: \(error.localizedDescription)"
}
else {
if let document = document {
do {
self.userInfo = try document.data(as: UserModel.self)!
completion()
}
catch {
print(error)
}
}
}
}
}
func fetchDegrees() {
let docRef = db.collection("DegreeCourses").document(userInfo.Tipocorso)
docRef.getDocument { document, error in
if let error = error as NSError? {
self.errorMsg = "Error getting document: \(error.localizedDescription)"
}
else {
if let document = document {
do {
self.userDegree = try document.data(as: userDegreeModel.self)!
}
catch {
print(error)
}
}
}
}
}
}
UserModel
import SwiftUI
import Firebase
import FirebaseDatabase
import FirebaseFirestoreSwift
public struct UserModel: Codable{
#DocumentID var id: String?
var Nome : String
var Cognome : String
var photoURL : String
var Nomeintero : String
var Corsodilaurea : String
var Tipocorso : String
}
extension UserModel {
static let empty = UserModel(Nome: "", Cognome: "", photoURL: "", Nomeintero: "", Corsodilaurea: "", Tipocorso: "")
}
userDegreeModel
import SwiftUI
import Firebase
import FirebaseDatabase
import FirebaseFirestoreSwift
struct userDegreeModel: Codable {
#DocumentID var id: String?
var Name : String
var TotalSubjects : Int
}
extension userDegreeModel {
static let empty = userDegreeModel(Name: "", TotalSubjects: 0)
}
Error
A couple of notes:
Firestore calls return on the main dispatch queue already about this), so you don't need to manually switch to the main queue using DispatchQueue.async { }. See my Twitter thread for more details.
Instead of mapping Firestore documents manually, you can use Codable to do so. This means less code to write, and fewer typos :-) Here is an article that goes into much more detail: Mapping Firestore Data in Swift - The Comprehensive Guide | Peter Friese
Accessing the signed in user using Auth.auth().currentUser!.uid might result in you app breaking if no user is signed in. I recommend implementing an authentication state listener instead.
Since all of Firebase's APIs are asynchronous (see my blog post about this: Calling asynchronous Firebase APIs from Swift - Callbacks, Combine, and async/await | Peter Friese), the result of fetchUser will take a short moment, so you want to make sure to only call fetchDegrees once that call has completed. One way to do this is to use a completion handler.
Lastly, I recommend following a styleguide like this one for naming your classes and attribute: Swift Style Guide
I've updated your code accordingly below.
import Firebase
import FirebaseDatabase
import FirebaseFirestoreSwift
import SwiftUI
public struct UserModel: Codable {
#DocumentID var id: String?
var firstName: String
var lastName: String
var photoUrl: String
// ...
}
extension UserModel {
static let empty = UserModel(firstName: "", lastName: "", photoUrl: "")
}
public struct UserDegreeModel: Codable {
#DocumentID var id: String?
var name: String
var totalSubjects: Int
// ...
}
extension UserDegreeModel {
static let empty = UserDegreeModel(name: "", totalSubjects: 0)
}
class ProfileViewModel: ObservableObject {
#Published var userInfo: UserModel = .empty
#Published var userDegree: UserDegreeModel = .empty
#Published var isSignedIn = false
let uid = Auth.auth().currentUser!.uid
let db = Firestore.firestore()
init() {
// listen for auth state change and set isSignedIn property accordingly
Auth.auth().addStateDidChangeListener { auth, user in
if let user = user {
print("Signed in as user \(user.uid).")
self.uid = user.uid
self.isSignedIn = true
}
else {
self.isSignedIn = false
self.username = ""
}
}
fetchUser() {
fetchDegrees()
}
}
func fetchUser(completion: () -> Void) {
let docRef = db.collection("users").document(uid)
docRef.getDocument { document, error in
if let error = error as NSError? {
self.errorMessage = "Error getting document: \(error.localizedDescription)"
}
else {
if let document = document {
do {
self.user = try document.data(as: UserModel.self)
completion()
}
catch {
print(error)
}
}
}
}
}
func fetchDegrees() {
let docRef = db.collection("DegreeCourses").document(userInfo.Tipocorso)
docRef.getDocument { document, error in
if let error = error as NSError? {
self.errorMessage = "Error getting document: \(error.localizedDescription)"
}
else {
if let document = document {
do {
self.userDegree = try document.data(as: UserDegreeModel.self)
}
catch {
print(error)
}
}
}
}
}
}
I am able to download the data & see it in the Xcode debug console when I print ("(products)" after completion(true) but when I try to use the products variable in the View Controller & print it's contents there I get an empty array []. How do I use the data after in a collection view after it is downloaded?
Model
import Foundation
import UIKit
import FirebaseFirestoreSwift
public struct StoreProducts: Codable {
#DocumentID var id: String?
var orderNumber: Int?
var country: String?
var description: String?
var price: Int?
var duration: String?
enum CodingKeys: String, CodingKey {
case orderNumber
case country
case description
case price
case duration
}
}
Model Class
import Foundation
import FirebaseFirestore
class StoreViewModel: ObservableObject {
public static let shared = StoreViewModel()
private let productsCollection: String = "products/country/subscription"
#Published var products : [StoreProducts]?
private var db = Firestore.firestore()
public func fetchProductData(completion: #escaping (Bool) -> Void) {
db.collection(canadianProductsCollection).getDocuments() { [self] (querySnapshot, err) in
//Handle Error:
if let err = err {
print("Error getting documents: \(err)")
completion(false)
} else {
//No Documents Found:
guard let documents = querySnapshot?.documents else {
print("no documents")
completion(false)
return
}
//Documents Found:
let products = documents.compactMap { document -> StoreProducts? in
return try! document.data(as: StoreProducts.self)
}
completion(true)
print ("\(products)")
}
}
}
}
View Controller
import Firebase
import FirebaseDatabase
class HomeViewController: UIViewController {
#ObservedObject private var storeViewModel = StoreViewModel()
override func viewWillAppear(_ animated: Bool) {
StoreViewModel.shared.fetchProductData(completion: { success in
if success {
print("Data loaded successfully")
print (storeViewModel.products)
} else {
//some break routine
}
})
}
}
You are storing the results from the database to a local variable and it is not passed on to your storeViewModel.
products = documents.compactMap { document -> StoreProducts? in
return try! document.data(as: StoreProducts.self)
}
I think removing the "let" might solve the problem.
So I'm trying to learn some Firestore basic functionality and have watched "Kilo Locos" videos on YouTube explaining CRUD operations. I want to take his method of code and create subcollections from it. Basically, how can I add a collection and make the 'User' collection a sub collection from this new collection. Any help is greatly appreciated, many thanks!!
Here is a link to download the project:
https://kiloloco.com/courses/youtube/lectures/3944217
FireStore Service
import Foundation
import Firebase
import FirebaseFirestore
class FIRFirestoreService {
private init() {}
static let shared = FIRFirestoreService()
func configure() {
FirebaseApp.configure()
}
private func reference(to collectionReference: FIRCollectionReference) -> CollectionReference {
return Firestore.firestore().collection(collectionReference.rawValue)
}
func create<T: Encodable>(for encodableObject: T, in collectionReference: FIRCollectionReference) {
do {
let json = try encodableObject.toJson(excluding: ["id"])
reference(to: collectionReference).addDocument(data: json)
} catch {
print(error)
}
}
func read<T: Decodable>(from collectionReference: FIRCollectionReference, returning objectType: T.Type, completion: #escaping ([T]) -> Void) {
reference(to: collectionReference).addSnapshotListener { (snapshot, _) in
guard let snapshot = snapshot else { return }
do {
var objects = [T]()
for document in snapshot.documents {
let object = try document.decode(as: objectType.self)
objects.append(object)
}
completion(objects)
} catch {
print(error)
}
}
}
func update<T: Encodable & Identifiable>(for encodableObject: T, in collectionReference: FIRCollectionReference) {
do {
let json = try encodableObject.toJson(excluding: ["id"])
guard let id = encodableObject.id else { throw MyError.encodingError }
reference(to: collectionReference).document(id).setData(json)
} catch {
print(error)
}
}
func delete<T: Identifiable>(_ identifiableObject: T, in collectionReference: FIRCollectionReference) {
do {
guard let id = identifiableObject.id else { throw MyError.encodingError }
reference(to: collectionReference).document(id).delete()
} catch {
print(error)
}
}
}
FIRCollectionReference
import Foundation
enum FIRCollectionReference: String {
case users
}
User
import Foundation
protocol Identifiable {
var id: String? { get set }
}
struct User: Codable, Identifiable {
var id: String? = nil
let name: String
let details: String
init(name: String, details: String) {
self.name = name
self.details = details
}
}
Encodable Extensions
import Foundation
enum MyError: Error {
case encodingError
}
extension Encodable {
func toJson(excluding keys: [String] = [String]()) throws -> [String: Any] {
let objectData = try JSONEncoder().encode(self)
let jsonObject = try JSONSerialization.jsonObject(with: objectData, options: [])
guard var json = jsonObject as? [String: Any] else { throw MyError.encodingError }
for key in keys {
json[key] = nil
}
return json
}
}
Snapshot Extensions
import Foundation
import FirebaseFirestore
extension DocumentSnapshot {
func decode<T: Decodable>(as objectType: T.Type, includingId: Bool = true) throws -> T {
var documentJson = data()
if includingId {
documentJson!["id"] = documentID
}
let documentData = try JSONSerialization.data(withJSONObject: documentJson!, options: [])
let decodedObject = try JSONDecoder().decode(objectType, from: documentData)
return decodedObject
}
}
The Firestore structure cannot have collection as children of other collections.
The answer to your question (How can I add a collection and make the 'User' collection a sub collection from this new collection?) is you cannot. Instead you must put a document between those two collections.
Read this for more information.
It says: Notice the alternating pattern of collections and documents. Your collections and documents must always follow this pattern. You cannot reference a collection in a collection or a document in a document.