This question already has answers here:
How to get data from firebase sub collection?
(2 answers)
Closed 14 days ago.
I need to get data from Users and then other collection Reservations. How can I make snapshot for sub collection?
Reservations = []
Firestore.firestore().collection("Users").getDocuments { (querySnapshot, error) in
if let e = error {
print(e)
}
else
{
if let snapshotDocuments = querySnapshot?.documents
{
for doc in snapshotDocuments
{
let data = doc.data()
// let rid = doc.documentID
if let Time = data["Time"] as? String, let Date = data["Date"] as? String, let Guests = data["Guests"] as? String, let RestaurantName = data["RestaurantName"] as? String, let Name = data["Name"] as? String, let Status = data["Status"] as? String, let Phone = data["Phone"] as? String
{
let newReservation = Reservation(restaurantName: RestaurantName, name: Name, phone: Phone, guests: Guests, time: Time, date: Date, status: Status)
self.Reservations.append(newReservation)
DispatchQueue.main.async {
print(self.Reservations)
self.reservationsTableView.reloadData()
}
}
}
}
}
}
If you want to read the reservations for the current user in your loop, you can do that with:
for doc in snapshotDocuments {
let reservationsRef = doc.collection("Reservations")
reservationsRef.getDocuments { (reservationsSnapshot, error) in
...
}
...
}
If you want to get all Reservations across the entire database in one go, you'll want to have a look at collection group queries.
Related
I am trying to get data from firestore collection and assign it to an array of dictionaries. for this part of the code below... i get the error "Cast from 'QuerySnapshot?' to unrelated type '[[String : Any]]' always fails" and the console prints "is not working".
guard let snap = snapshot as? [[String:Any]] else {
print("is not working")
completion(.failure(DatabaseError.failedToFetch))
return
}
Here is the full code.
// fetches and returns all conversations for the user with passed in uid
public func getAllConversations(for uid: String, completion: #escaping(Result<[Conversation], Error>) -> Void) {
print("fetching all convos")
//NEW
let db = Firestore.firestore()
let CurrentUser = Auth.auth().currentUser?.uid
let ListRef = db.collection("users").document(CurrentUser!).collection("conversations")
// fetch the current users convo list
ListRef.getDocuments { snapshot, error in
if let err = error {
debugPrint("Error fetching documents: \(err)")
} else {
guard let snap = snapshot as? [[String:Any]] else {
print("is not working")
completion(.failure(DatabaseError.failedToFetch))
return
}
print("is working")
let conversations: [Conversation] = snap.compactMap({ dictionary in
guard let id = dictionary["id"] as? String,
let name = dictionary["name"] as? String,
let otherUserUID = dictionary["other_user-uid"] as? String,
let latestMessage = dictionary["latest-message"] as? [String:Any],
let date = latestMessage["date"] as? String,
let message = latestMessage["message"] as? String,
let isRead = latestMessage["is-read"] as? Bool else {
return nil
}
//save other user ID to a global var
self.test = otherUserUID
//assign data into an array of dictionaries
let latestConvoObject = LatestMessage(date: date, text: message, isRead: isRead)
return Conversation(id: id, name: name, otherUserUid: otherUserUID, latestMessage: latestConvoObject)
})
completion(.success(conversations))
}
}
}
There are a numbers of way to read that data, and the process can be simplified by conforming objects to the codable protocol but let me provide a straight forward example. I don't know what your Conversation object looks like so here's mine
class ConversationClass {
var from = ""
var to = ""
var msg = ""
var timestamp = 0
convenience init(withDoc: DocumentSnapshot) {
self.init()
self.from = withDoc.get("from") as? String ?? "no from"
self.to = withDoc.get("to") as? String ?? "no to"
self.msg = withDoc.get("msg") as? String ?? "no msg"
self.timestamp = withDoc.get("timestamp") as? Int ?? 0
}
}
and then here's the the code that reads in all the conversation documents from a Collection, stores each in a ConversationClass object, puts those in an array and returns it through an escaping completion handler
func getConversations(completion: #escaping( [ConversationClass] ) -> Void) {
let conversationCollection = self.db.collection("conversations")
conversationCollection.getDocuments(completion: { snapshot, error in
if let err = error {
print(err.localizedDescription)
return
}
guard let docs = snapshot?.documents else { return }
var convoArray = [ConversationClass]()
for doc in docs {
let convo = ConversationClass(withDoc: doc)
convoArray.append(convo)
}
completion(convoArray)
})
}
I am trying to fetch data from firebase firestore. The problem i have is that my fetch is returning the results x4 times. For example when i do print(name) it print the users name x4 times.
I think there may be a loop that is not working correctly?
// fetches and returns all conversations for the user with passed in uid
public func getAllConversations(for uid: String, completion: #escaping(Result<[Conversation], Error>) -> Void) {
let CurrentUser = Auth.auth().currentUser?.uid
let db = Firestore.firestore()
let ConversationRef = db.collection("users").document(CurrentUser!).collection("conversations").document(
"jVymlfbpuAYQQ9Brf8SbUZ7KCGg1")
// get the otherUserUId TO DO
ConversationRef.getDocument { snapshot, error in
if error != nil {
print("Error connecting to database")
} else {
if let document = snapshot {
if document.exists {
let data = document.data()
print(data)
let conversations: [Conversation] = data!.compactMap ({ dictionary in
guard let conversationId = data!["id"] as? String,
let name = data!["name"] as? String,
let otherUserUid = data!["other_user-uid"] as? String,
let latestMessage = data!["latest-message"] as? [String:Any],
let date = latestMessage["date"] as? String,
let message = latestMessage["message"] as? String,
let isRead = latestMessage["is-read"] as? Bool
else {
return nil
}
print(name)
let latestMessageObject = LatestMessage(date: date, text: message, isRead: isRead)
return Conversation(id: conversationId, name: name, otherUserUid: otherUserUid, latestMessage: latestMessageObject)
})
completion(.success(conversations))
}
else {
completion(.failure(DatabaseError.failedToFetch))
return
}
}
}
}
}
Please note that ConversationRef.getDocument{..} will only Return One Specific Document, which you’re Referring here :
let ConversationRef = db.collection("users").document(CurrentUser!).collection("conversations").document("jVymlfbpuAYQQ9Brf8SbUZ7KCGg1”)
So the let data = document.data()
will be single [String:Any] object(in this case Single ‘Conversation’),
not the Array of Dictionaries(eg: [Conversations]).
Try doing it this way:
// fetches and returns all conversations for the user with passed in uid
public func getAllConversations(for uid: String, completion: #escaping(Result<Conversation, Error>) -> Void) {
let CurrentUser = Auth.auth().currentUser?.uid
let db = Firestore.firestore()
let ConversationRef = db.collection("users").document(CurrentUser!).collection("conversations").document(
"jVymlfbpuAYQQ9Brf8SbUZ7KCGg1")
// get the otherUserUId TO DO
ConversationRef.getDocument { snapshot, error in
if error != nil {
print("Error connecting to database")
} else {
if let document = snapshot {
if document.exists {
if let data = document.data() {
if let conversationId = data["id"] as? String,
let name = data["name"] as? String,
let otherUserUid = data["other_user-uid"] as? String,
let latestMessage = data["latest-message"] as? [String:Any],
let date = latestMessage["date"] as? String,
let message = latestMessage["message"] as? String,
let isRead = latestMessage["is-read"] as? Bool {
print(name)
let latestMessageObject = LatestMessage(date: date, text: message, isRead: isRead)
let conversations = Conversation(id: conversationId, name: name, otherUserUid: otherUserUid, latestMessage: latestMessageObject)
completion(.success(conversations))
}
}
}
else {
completion(.failure(DatabaseError.failedToFetch))
return
}
}
}
}
}
// fetches and returns all conversations for the user with passed in uid
public func getAllConversations(for uid: String, completion: #escaping(Result<[Conversation], Error>) -> Void) {
let CurrentUser = Auth.auth().currentUser?.uid
let db = Firestore.firestore()
let ConversationRef = db.collection("users").document(CurrentUser!).collection("conversations")
ConversationRef.addSnapshotListener { snapshot, error in
if error != nil {
print("Error connecting to database")
} else {
guard let snap = snapshot else {
completion(.failure(DatabaseError.failedToFetch))
return
}
for document in snap.documents {
let data = document.data()
print(data)
guard let conversationId = data["id"] as? String,
let name = data["name"] as? String,
let otherUserUid = data["other_user-uid"] as? String,
let latestMessage = data["latest-message"] as? [String:Any],
let date = latestMessage["date"] as? String,
let message = latestMessage["message"] as? String,
let isRead = latestMessage["is-read"] as? Bool else {
return
}
print(name)
let latestMessageObject = LatestMessage(date: date, text: message, isRead: isRead)
let conversations = [Conversation(id: conversationId, name: name, otherUserUid: otherUserUid, latestMessage: latestMessageObject)]
completion(.success(conversations))
}
}
}
}
I wonder how to get an Dictionary from my Firestore. For normal Arrays I've done it like that:
func returnArray(){
let newpath = Firestore.firestore().collection(path)
newpath.addSnapshotListener { (querySnapshot, error) in
guard let documents = querySnapshot?.documents else {
return
}
self.Array = documents.map { (queryDocumentSnapshot) -> String in
let data = queryDocumentSnapshot.data()
let Name = data["myField"] as? String ?? ""
return Name
}
}
}
That works perfectly fine. My question is now how I have to change my code that its getting an Array out of the Firebase. I had an idea, but it doesn't work:
func returnDictionary(){
let newpath = Firestore.firestore().collection(path)
newpath.addSnapshotListener { (querySnapshot, error) in
guard let documents = querySnapshot?.documents else {
return
}
self.Dictionary = documents.map { (queryDocumentSnapshot) -> // I don't know what to fill here
in
let data = queryDocumentSnapshot.data()
let Name = data["AnzeigeName"] as? String ?? ""
let ID = data["selfID"] as? String ?? ""
return ID: Name
}
}
}
What can I try next?
.map is going to give you an array, but you can use Dictionary's init(uniqueKeysWithValues:) to turn this into a Dictionary:
let dictionary : Dictionary<String,String> = .init(uniqueKeysWithValues: documents.compactMap { queryDocumentSnapshot -> (String,String)? in
let data = queryDocumentSnapshot.data()
if let name = data["AnzeigeName"] as? String, let id = data["selfID"] as? String {
return (id, name)
}
return nil
})
It's important to know that uniqueKeysWithValues will crash if the keys are not in fact unique, so you'd want to check for that first (look at #New Dev's comment about init(_:uniquingKeysWith:) to handle this). I'm also using compactMap to get rid of nil values.
(Note: In Swift, generally variable names are lowercased and type names are uppercased. Going against that pattern can make your code challenging to read for others)
Firestore Example
{
name: "Anonymous"
pet {
name: "Max"
age: "3"
}
}
Query
Firebase.firestore().collection(path).getDocuments { querySnapshot, error in
if let error = error {
print(error.localizedDescription)
} else {
for document in querySnapshot!.documents {
let data = document.data()
let name = data["name"]
let pet = data["pet"] as! Dictionary<String, String>
print("Name: \(name)")
print("Pet-name: \(pet["name"]!)")
print("Pet-age: \(pet["age"]!)")
}
I have this class CurrentUser that manages the currently logged in user and pulls the data for that user from Firebase.
One of CurrentUser's attributes is userEventIDs. I also have a collection of Events documents. Each user has their own array of event IDs that correspond to the events within the Events collection in my Firestore database.
On the MyAccount view struct I have an onAppear method that queries the Events collection based on the currentUser's array of eventIds, returns those Events, and then sorts them to be either before or after today based on the date of the event.
Currently the eventIds load in the first time this view is opened, but the query from the events comes back blank twice and only after the view is switched to another one and back to the MyAccount view will the page populate with these events.
Is there something I can do to make the events load on the first time the view is opened?
CurrentUser
class CurrentUser: ObservableObject {
let user = Auth.auth().currentUser
#Published var currentUserInformation = User(id: "", name: "", email: "'", accountType: "", profPicURL: "", coverPhotoURL: "", numberFollowers: nil, description: nil, location: nil, websiteLink: nil, orgID: nil, userEventIDs: [String](), userEvents: [Event]())
init() {
getUserInformation()
}
func getUserInformation() {
let UID = user!.uid
let database = Firestore.firestore()
database.collection("Organizers").whereField("Organizer ID", isEqualTo: UID).getDocuments() { (querySnapshot, err) in
if err != nil {
print("Error getting documents: \(err!)")
}
for document in querySnapshot!.documents {
self.currentUserInformation.id = document.documentID
self.currentUserInformation.name = document.get("Organization Name") as! String
self.currentUserInformation.email = document.get("Email") as! String
self.currentUserInformation.accountType = document.get("Account Type") as! String
self.currentUserInformation.profPicURL = document.get("Profile Pic URL") as! String
self.currentUserInformation.coverPhotoURL = document.get("Cover Pic URL") as! String
self.currentUserInformation.numberFollowers = (document.get("Number of Followers") as! Int)
self.currentUserInformation.description = (document.get("Organization Description") as! String)
self.currentUserInformation.websiteLink = (document.get("Organization Website Link") as! String)
self.currentUserInformation.location = (document.get("Organization Location") as! String)
self.currentUserInformation.orgID = (document.get("Organizer ID") as! String)
self.currentUserInformation.userEventIDs = (document.get("Events") as! [String])
self.currentUserInformation.accountType = "Organizer"
}
}
if self.currentUserInformation.id == "" {
database.collection("Activists").whereField("UID", isEqualTo: UID).getDocuments() { (querySnapshot, err) in
if err != nil {
print("Error getting documents: \(err!)")
}
for document in querySnapshot!.documents {
self.currentUserInformation.id = document.documentID
let firstName = document.get("First Name") as! String
let lastName = document.get("Last Name") as! String
self.currentUserInformation.name = "\(firstName) \(lastName)"
self.currentUserInformation.email = document.get("Email") as! String
self.currentUserInformation.accountType = "Activist"
self.currentUserInformation.profPicURL = document.get("Profile Pic") as! String
self.currentUserInformation.userEventIDs = (document.get("Events") as! [String])
}
}
}
}
func getUserEvents() {
let database = Firestore.firestore()
let eventRef = database.collection("Events")
for eventID in self.currentUserInformation.userEventIDs {
for event in self.currentUserInformation.userEvents {
if event.id == eventID {
break
}
}
eventRef.document(eventID).getDocument() { (document, error) in
if let document = document {
let id = document.documentID
let eventTitle = document.get("Name") as! String
let organizer = document.get("Organizer") as! String
let organizerID = document.get("Organizer ID") as! String
let eventDescription = document.get("Description") as! String
let date = document.get("Date") as! String
let time = document.get("Time") as! String
let location = document.get("Location") as! String
let numAttending = document.get("Number Attending") as! Int
let eventPhotoURL = document.get("Event Photo URL") as! String
self.currentUserInformation.userEvents.append(Event(id: id, eventTitle: eventTitle, eventOrganizer: organizer, eventOrganizerID: organizerID, eventDescription: eventDescription, date: date, time: time, location: location, numAttending: numAttending, eventPhotoURL: eventPhotoURL))
} else {
print("Document does not exist")
}
}
}
}
}
View
.onAppear() {
if currentActivist.currentUserInformation.userEvents.count != currentActivist.currentUserInformation.userEventIDs.count {
currentActivist.getUserEvents()
print("Getting user events")
}
pastEvents = MyAccountActivistView.getSortedEvent(actEvents: currentActivist.currentUserInformation.userEvents)["Past"]!
futureEvents = MyAccountActivistView.getSortedEvent(actEvents: currentActivist.currentUserInformation.userEvents)["Upcoming"]!
}
A couple of quick notes:
Most Firebase calls are asynchronous (check out this article to understand why), so your call to Auth.auth().currentUser is most likely going to return nil. Instead, you should register an AuthenticationStateListener. See this sample code to see how it's done.
Instead of instantiating an empty User instance, make currentUserInformation optional
Mapping data is much easier using Firestore's support for Codable. I've written extensively about this, but the gist of it is, you'll be able to map documents with a single line of code (instead of having to manually map every single field). The Firestore documentation actually has a nice code snippet that you can adopt:
let docRef = db.collection("cities").document("BJ")
docRef.getDocument { (document, error) in
// Construct a Result type to encapsulate deserialization errors or
// successful deserialization. Note that if there is no error thrown
// the value may still be `nil`, indicating a successful deserialization
// of a value that does not exist.
//
// There are thus three cases to handle, which Swift lets us describe
// nicely with built-in Result types:
//
// Result
// /\
// Error Optional<City>
// /\
// Nil City
let result = Result {
try document?.data(as: City.self)
}
switch result {
case .success(let city):
if let city = city {
// A `City` value was successfully initialized from the DocumentSnapshot.
print("City: \(city)")
} else {
// A nil value was successfully initialized from the DocumentSnapshot,
// or the DocumentSnapshot was nil.
print("Document does not exist")
}
case .failure(let error):
// A `City` value could not be initialized from the DocumentSnapshot.
print("Error decoding city: \(error)")
}
}
Avoid force unwrapping (using the ! operator), use optional unwrapping (using the ? operator), and the nil-coalescing operator (??) instead
Database Structure
futsal_list.document(futsal_uid).collection("book_info").document(date in format "May 9, 2019".collection("newrequest").document(userUid)
and in useruid there is map like
time[
6AM : timestamp
7AM : timstamp,
]
I am using google cloud firestore and i want to retrieve all the new request from all the dates and it need to be realtime listener. I also want to divide the table view section according to the date. And i am only showing the today and upcoming dates and no past dates.
problem -
when a new request arrived the table add the single request multiple times in the table and when i go back and come to the view then the data shown are fine.
this is what i have tried
func loadAllRequestFromFirebasee() {
db.collection("futsal_list").document(currentUser!.uid).collection("book_info").addSnapshotListener { (querySnapshot, error) in
guard let snapshot = querySnapshot else {
print("Error fetching snapshots: \(error!)")
return
}
self.newRequestArray.removeAll()
self.sectionHeader.removeAll()
var validDates = [String] ()
for document in snapshot.documents {
let bookedDate = document.documentID
if !self.isPastDate(date: bookedDate) {
validDates.append(bookedDate)
}
}
for (bookedDateIndex, bookedDate) in validDates.enumerated() {
self.db.collection("futsal_list").document(self.currentUser!.uid).collection("book_info").document(bookedDate).collection("newrequest").getDocuments(completion: { (uidSnapshots, error) in
guard let uidSnapshot = uidSnapshots else {
print("Error fetching snapshots: \(error!)")
return
}
let userUids = uidSnapshot.documents
if userUids.count > 0 {
self.newRequestArray.append([])
self.sectionHeader.append(bookedDate)
for document in userUids {
print("\(document.documentID) => \(document.data())")
let dataDescription = document.data()
let userUid = document.documentID
let bookedTimes = dataDescription["time"] as! [String : Any]
self.db.collection("users_list").document(userUid).getDocument(completion: { (document, error) in
if let document = document, document.exists {
let data = document.data()
let userName = data!["user_full_name"] as? String ?? ""
// let futsalAddress = data!["futsal_address"] as? String ?? ""
let userPhone = data!["user_phone_number"] as? String ?? ""
let userProfilePic = data!["user_profile_image"] as? String ?? ""
for time in bookedTimes.keys {
let newRequest = NewRequest(userUid: userUid, userName: userName, bookDate: bookedDate, bookTime: time, userPhoneNumber: userPhone, userProfilePicture: userProfilePic)
self.newRequestArray[bookedDateIndex].append(newRequest)
self.newBookRequestTableView.reloadData()
}
}
})
}
}
})
}
}
}