Running into the Error: keyNotFound, DecodingError when trying to fetch messages from Firebase Database - swift

Question

I get this Error:
keyNotFound(CodingKeys(stringValue: "email", intValue: nil),
Swift.DecodingError.Context(codingPath: [], debugDescription: "No value associated with
key CodingKeys(stringValue: \"email\", intValue: nil) (\"email\").", underlyingError: nil))
I am not sure what this Error is trying to tell me, I read through this question: Swift Error- keyNotFound(CodingKeys(stringValue:, intValue: nil), Swift.DecodingError.Context, which has the same Error. Though I couldn't figure out how to change my ChatUser so that my App works.
Trying to fetch messages from my Firestore database.
I tried debugging and I am pretty sure
ForEach(vm.recentMessages) { recentMessage in } leads to the error.
This is my ViewModel:
class MessagesViewModel: ObservableObject {
#Published var errorMessage = ""
#Published var chatUser: ChatUser?
init() {
fetchCurrentUser()
fetchRecentMessages()
}
#Published var recentMessages = [RecentMessage]()
private var firestoreListener: ListenerRegistration?
func fetchRecentMessages() {
guard let uid = FirebaseManager.shared.auth.currentUser?.uid else { return }
firestoreListener?.remove()
self.recentMessages.removeAll()
firestoreListener = FirebaseManager.shared.firestore
.collection(FirebaseConstants.recentMessages)
.document(uid)
.collection(FirebaseConstants.messages)
.order(by: FirebaseConstants.timestamp)
.addSnapshotListener { querySnapshot, error in
if let error = error {
self.errorMessage = "Failed to listen for recent messages: \(error)"
print(error)
return
}
querySnapshot?.documentChanges.forEach({ change in
let docId = change.document.documentID
if let index = self.recentMessages.firstIndex(where: { rm in
return rm.id == docId
}) {
self.recentMessages.remove(at: index)
}
do {
let rm = try change.document.data(as: RecentMessage.self)
self.recentMessages.insert(rm, at: 0)
} catch {
print(error)
}
})
}
}
func fetchCurrentUser() {
guard let uid = FirebaseManager.shared.auth.currentUser?.uid else {
self.errorMessage = "Could not find firebase uid"
return
}
FirebaseManager.shared.firestore.collection("users").document(uid).getDocument { snapshot, error in
if let error = error {
self.errorMessage = "Failed to fetch current user: \(error)"
print("Failed to fetch current user:", error)
return
}
self.chatUser = try? snapshot?.data(as: ChatUser.self)
FirebaseManager.shared.currentUser = self.chatUser
}
}
FirebaseManager.shared.firestore.collection("users").document(uid).getDocument { snapshot, error in
if let error = error {
self.errorMessage = "Failed to fetch current user: \(error)"
print("Failed to fetch current user:", error)
return
}
self.chatUser = try? snapshot?.data(as: ChatUser.self)
FirebaseManager.shared.currentUser = self.chatUser
}
}
}
This is the View the messages should appear in:
struct MessagesView: View {
#ObservedObject private var vm = MessagesViewModel()
private var chatLogViewModel = ChatLogViewModel(chatUser: FirebaseManager.shared.currentUser)
#State var chatUser: ChatUser?
var body: some View {
VStack {
HStack {
Button() {
} label: {
Image("search").resizable()
.frame(width: 32, height: 32)
.padding(.leading, 11)
}
Spacer()
Image("AppIcon").resizable()
.frame(width: 32, height: 32)
.scaledToFill()
Spacer()
Button() {
} label: {
Image("dots").resizable()
.renderingMode(.template)
.frame(width: 32, height: 32)
.foregroundColor(Color(.init(red: 0.59, green: 0.62, blue: 0.67, alpha: 1)))
.padding(.trailing, 9)
.offset(y: -4)
}
}.padding(.init(top: 0, leading: 8, bottom: 0, trailing: 8))
NavigationView {
VStack {
messagesView
}
}
}
}
private var messagesView: some View {
ScrollView {
ForEach(vm.recentMessages) { recentMessage in
VStack {
Button {
let uid = FirebaseManager.shared.auth.currentUser?.uid == recentMessage.fromId ? recentMessage.toId : recentMessage.fromId
self.chatUser = .init(id: uid, uid: uid, email: recentMessage.email, profileImageUrl: recentMessage.profileImageUrl)
self.chatLogViewModel.chatUser = self.chatUser
self.chatLogViewModel.fetchMessages()
} label: {
HStack(spacing: 16) {
WebImage(url: URL(string: recentMessage.profileImageUrl))
.resizable()
.scaledToFill()
.frame(width: 64, height: 64)
.clipped()
.cornerRadius(64)
.overlay(RoundedRectangle(cornerRadius: 64)
.stroke(Color.black, lineWidth: 1))
.shadow(radius: 5)
VStack(alignment: .leading, spacing: 8) {
Text(recentMessage.username)
.font(.system(size: 16, weight: .bold))
.foregroundColor(Color(.label))
.multilineTextAlignment(.leading)
Text(recentMessage.text)
.font(.system(size: 14))
.foregroundColor(Color(.darkGray))
.multilineTextAlignment(.leading)
}
Spacer()
Text(recentMessage.timeAgo)
.font(.system(size: 14, weight: .semibold))
.foregroundColor(Color(.label))
}
}
Divider()
.padding(.vertical, 8)
}.padding(.horizontal)
}.padding(.bottom, 50)
}
}
}
ChatUser looks like this:
import FirebaseFirestoreSwift
struct ChatUser: Codable, Identifiable {
#DocumentID var id: String?
let uid, email, profileImageUrl: String
}
struct RecentMessage: Codable, Identifiable {
#DocumentID var id: String?
let text, email: String
let fromId, toId: String
let profileImageUrl: String
let timestamp: Date
var username: String {
email.components(separatedBy: "#").first ?? email
}
var timeAgo: String {
let formatter = RelativeDateTimeFormatter()
formatter.unitsStyle = .abbreviated
return formatter.localizedString(for: timestamp, relativeTo: Date())
}
}

Answer 1

Update
I made some adjustments and added the RecentMessage portion. Now it works entirely for me. I can get the current (ChatUser) from Firestore and I also can get the RecentMessages. Now it loads all RecentMessages, this should be changes to ones that are in relationship with the current user.
Models
ChatUser
import Foundation
import SwiftUI
import Firebase
struct ChatUser: Codable, Identifiable, Hashable {
var id: String?
var email: String
var profileImageUrl: String
var uid: String
init(email: String, profileImageUrl: String, uid: String, id: String?) {
self.id = id
self.email = email
self.profileImageUrl = profileImageUrl
self.uid = uid
}
init?(document: DocumentSnapshot) {
let data = document.data()
let email = data!["email"] as? String ?? ""
let profileImageUrl = data!["profileImageUrl"] as? String ?? ""
let uid = data!["uid"] as? String ?? ""
id = document.documentID
self.email = email
self.profileImageUrl = profileImageUrl
self.uid = uid
}
enum CodingKeys: String, CodingKey {
case id
case email
case profileImageUrl
case uid
}
}
extension ChatUser: Comparable {
static func == (lhs: ChatUser, rhs: ChatUser) -> Bool {
return lhs.id == rhs.id
}
static func < (lhs: ChatUser, rhs: ChatUser) -> Bool {
return lhs.email < rhs.email
}
}
RecentMessage
struct RecentMessage: Codable, Identifiable, Hashable {
var id: String?
var text: String
var email: String
var fromId: String
var toId: String
var profileImageUrl: String
var timestamp: Date
init(text: String, email: String, fromId: String, toId: String, profileImageUrl: String, timestamp: Date, id: String?) {
self.id = id
self.text = text
self.email = email
self.fromId = email
self.toId = email
self.profileImageUrl = profileImageUrl
self.timestamp = timestamp
}
init?(document: DocumentSnapshot) {
let data = document.data()
let text = data!["text"] as? String ?? ""
let email = data!["email"] as? String ?? ""
let fromId = data!["fromId"] as? String ?? ""
let toId = data!["toId"] as? String ?? ""
let profileImageUrl = data!["profileImageUrl"] as? String ?? ""
let timestamp = data!["timestamp"] as? Date ?? Date()
id = document.documentID
self.text = text
self.email = email
self.fromId = fromId
self.toId = toId
self.profileImageUrl = profileImageUrl
self.timestamp = timestamp
}
enum CodingKeys: String, CodingKey {
case id
case text
case email
case fromId
case toId
case profileImageUrl
case timestamp
}
func getUsernameFromEmail() -> String {
return email.components(separatedBy: "#").first ?? email
}
func getElapsedTime() -> String {
let formatter = RelativeDateTimeFormatter()
formatter.unitsStyle = .abbreviated
return formatter.localizedString(for: timestamp, relativeTo: Date())
}
}
extension RecentMessage: Comparable {
static func == (lhs: RecentMessage, rhs: RecentMessage) -> Bool {
return lhs.id == rhs.id
}
static func < (lhs: RecentMessage, rhs: RecentMessage) -> Bool {
return lhs.timestamp < rhs.timestamp
}
}
ViewModels
One thing in advance, instead of using FirebaseManager.shared, I declared once in the ViewModel:
let db = Firestore.firestore()
I split the existing MessagesViewModel into MessagesViewModel and UserViewModel
I added a completion block to the fetchCurrentUser function.
It must be completed first (successfully) to run the fetchRecentMessage function. With that block we do 2 things:
make sure the fetchCurrentUser function is completed. I assume, even if the id is saved to the database, in your init function the fetchRecentMessage function will be called before you got the data for the currentUser. It is asynchronous and your code is not waiting for Firestore to be finished.
make sure that chatUser really is initialized with the values from Firestore.
UserViewModel
class UsersViewModel: ObservableObject {
let db = Firestore.firestore()
#Published var errorMessage = ""
#Published var chatUser: ChatUser?
func fetchCurrentUser(_ completion: #escaping (Bool, String) ->Void) {
guard let uid = Auth.auth().currentUser?.uid else {
self.errorMessage = "Could not find firebase uid"
completion(false, self.errorMessage)
return
}
let docRef = self.db.collection("chatUsers").document(uid)
docRef.getDocument { (document, error) in
if let document = document, document.exists {
self.chatUser = ChatUser(document: document)
completion(true, "ChatUser set up from Firestore db")
} else {
self.errorMessage = "ChatUser document not found"
completion(false, self.errorMessage)
}
}
}
}
MessagesViewModel
class MessagesViewModel: ObservableObject {
let db = Firestore.firestore()
#Published var errorMessage = ""
#Published var recentMessages: [RecentMessage] = []
private var firestoreListener: ListenerRegistration?
func fetchData(_ completion: #escaping (Bool, String) ->Void) {
self.recentMessages.removeAll()
db.collection("recentMessages").addSnapshotListener { (querySnapshot, error) in
guard let documents = querySnapshot?.documents else {
self.errorMessage = "No documents"
completion(true, self.errorMessage)
return
}
self.recentMessages = documents.map { queryDocumentSnapshot -> RecentMessage in
return RecentMessage(document: queryDocumentSnapshot)!
}
completion(true, "Data fetched")
}
}
}
Views
ContentView
The ContentView just opens the next view MusicBandFanView(), when the MusicBandFanView() appears it first calls the fetchCurrentUser() function and when the completion block of that function is completed, it calls the fetchRecentMessages() function
struct ContentView: View {
#Environment(\.managedObjectContext) private var viewContext
#EnvironmentObject var usersViewModel: UsersViewModel
#EnvironmentObject var messagesViewModel: MessagesViewModel
#EnvironmentObject var authViewModel: AuthViewModel
var body: some View {
MusicBandFanView()
.onAppear {
usersViewModel.fetchCurrentUser({ (success, logMessage) -> Void in
if success {
print(logMessage)
messagesViewModel.fetchData({ (success, logMessage) -> Void in
print(logMessage)
})
} else {
print(logMessage)
}
})
}
}
}
MusicBandFanView
This is the first part of your view. I just change the messageView from a var within the MusicBandFanView to a distinct view.
Since I don't have your images you use, I used SF-Symbols instead.
struct MusicBandFanView: View {
#Environment(\.managedObjectContext) private var viewContext
#EnvironmentObject var usersViewModel: UsersViewModel
#EnvironmentObject var messagesViewModel: MessagesViewModel
#EnvironmentObject var authViewModel: AuthViewModel
var body: some View {
VStack() {
HStack {
Button() {
} label: {
Image(systemName: "magnifyingglass")
.frame(width: 32, height: 32)
.padding(.leading, 11)
}
Spacer()
Image(systemName: "applelogo")
.frame(width: 32, height: 32)
.scaledToFill()
Spacer()
Button() {
} label: {
Image(systemName: "ellipsis")
.renderingMode(.template)
.frame(width: 32, height: 32)
.foregroundColor(Color(.init(red: 0.59, green: 0.62, blue: 0.67, alpha: 1)))
.padding(.trailing, 9)
.offset(y: -4)
}
}.padding(.init(top: 0, leading: 8, bottom: 0, trailing: 8))
NavigationView {
VStack {
Text("messages")
MessagesView()
}
}
}
}
}
MessagesView
That is what you put into a var.
I don't really got what you tried with the button, but I guess you can add that portion similar to the exiting code.
Since I didn't install SDWebimages for the test environment here, I just used an alternative SF-Symbol.
struct MessagesView: View {
#Environment(\.managedObjectContext) private var viewContext
#EnvironmentObject var usersViewModel: UsersViewModel
#EnvironmentObject var messagesViewModel: MessagesViewModel
#EnvironmentObject var authViewModel: AuthViewModel
var body: some View {
ScrollView {
VStack {
ForEach(messagesViewModel.recentMessages, id: \.self){ recentMessage in
Button {
// I don't really get what you try to do here. The user is already logged in and the fetch for the chatUser (current user) has already been performed.
} label: {
HStack(spacing: 16) {
Image(systemName: "person.crop.circle.fill")
.resizable()
.scaledToFill()
.frame(width: 64, height: 64)
.clipShape(Circle())
.overlay(Circle()
.stroke(Color.black, lineWidth: 1))
.shadow(radius: 5)
VStack(alignment: .leading, spacing: 8) {
Text(recentMessage.getUsernameFromEmail())
.font(.system(size: 16, weight: .bold))
.foregroundColor(Color(.label))
.multilineTextAlignment(.leading)
Text(recentMessage.text)
.font(.system(size: 14))
.foregroundColor(Color(.darkGray))
.multilineTextAlignment(.leading)
}
Spacer()
Text("\(recentMessage.getElapsedTime())")
.font(.system(size: 14, weight: .semibold))
.foregroundColor(Color(.label))
}
}
Divider()
.padding(.vertical, 8)
}
.padding(.horizontal)
}
.padding(.bottom, 50)
}
}
}
Screenshots
App Screenshot from simulator
Firestore Console Output ChatUser
Firestore Console Output RecentMessage