Hi code crew 
Although I am familiar working with documents, I noticed today my brain went blank when I tried working with 1 document only in Firestore.
I want to pull data from 1 document that has just 2 fields in it: avHeight and avWater. Both are numbers and I want to use them through my Model.
This is a snippet of my Model:
struct CareData {
var avHeight: Int
var avWater: Int
}
And here a snippet of my ViewModel:
@Published var careData = [CareData]()
func getCareData(documentName: String) -> Int {
let collectionCare = database.collection("collection-name").document(documentName)
// Get the document
collectionCare.getDocument { snapshot, error in
// Check for errors
if error == nil {
// No errors
if let snapshot = snapshot {
return CareData(avHeight: (["avHeight"] as? Int)!, avWater: (["avWater"] as? Int)!) // error message
}
}
else {
// Handle the error
}
}
}
After return, I get this error message: Unexpected non-void return value in void function.
I thought only function() returns a void, but mine has an Integer defined as an output.
I am not sure if my function needs to be corrected or if I am approaching this all wrong. I modelled my function after the ones I learned in the Firebase courses here on CWC, but all of them worked with getDocuments, not getDocument.
Hope anyone here can help, as I didnât find anything helpful on Stackoverflow or Google 
This is doing multiple things
Itâs trying to typecast for an Int and then is force unwrapping it
You could separate these steps to make it more clear to you
Also you should be returning CareData, not an Int, thatâs how youâve written the actual body of the function
It seems like youâre not using the snapshot properly? If you print it after the if let snapshot = snapshot whatâs printed?
When I print the snapshot, it prints <FIRDocumentSnapshot: somenumber>. So I assume this one is working?
When I replace -> Int with -> CareData I still get the same error message.
What confuses me, is why I even need to define what I want to return here. We didnât do that in the database course when retrieving the modules for the Learning App either and I thought this is very similar, except I use only 1 document and for the learning app we queried through multiple documents.
@liviusminimus
Hi Livia,
You have defined careData as an array. ie:
@Published var careData = [CareData]()
That being the case your getCareData function really should be written like this:
func getCareData() {
let collectionCare = database.collection("collection-name")
// Get the document
collectionCare.getDocuments { snapshot, error in
// Check for errors
if error == nil {
// No errors
if let snapshot = snapshot {
for doc in snapshot.documents {
let newItem = CareData(avHeight: doc["avHeight"] as? Int ?? 0, avWater: doc["avWater"] as? Int ?? 0)
self.careData.append(newItem)
}
}
}
else {
// Handle the error
}
}
}
I tested that here on a Firebase project I use for testing purposes and it works after having created a collection named âcollection-nameâ with the two fields named the same like this (which I am assuming is what you have ??):
I just refactored my entire function, as I seemed to be on the completely wrong path.
However, I am running into a new error message now that I donât understand how to fix
Trailing closure passed to parameter of type âFirestoreSourceâ that does not accept a closure
func getCareData(documentName: String) {
let collectionCare = database.collection("collection-name").document(documentName)
// Get the Document
collectionCare.getDocument { document, error in // new error! Yay...
let avHeight = document!.get("avHeight")
let avWater = document!.get("avWater")
// add to Care Data Model
return CareData(avHeight: avHeight, avWater: avWater)
}
}
I am trying hard to understand where I am passing a closure here and why it is not accepted. This must be for sure something obvious for anyone with more experience, but I still consider myself a beginner
Can you provide a screenshot of your Firebase Console showing your collection and the two fields in that collection?
Apologies Chris, I just saw your reply after I added my recent update. Yes, my Firebase setup pretty much looks like this.
Your code works perfectly, so thank you big time for the help! 
Looking at it, it makes perfect sense to use a loop and append the results to the array. I didnât even think about that, as I thought itâs just 2 values in 1 doc. Thank you big time, there is still a lot to learn for me
Edit: here we go with the screenshot. Exactly what you posted.
Yes, Firebase is tricky to get your head around and itâs taken me months to get a handle on it.
Iâm pretty sure that Chris Ching has had way more experience with it than I given that he has been a Developer a lot longer than me AND back in the days using Objective C.
