Get Document from current user firebase swift

Question

I'm trying to get the firstname from this:

The user is logged in and I can access his uid, but I can't get the Document that belongs to that user, this is how I'm trying to do it:

    private func getDocument() {

        var userID = Auth.auth().currentUser?.uid
            userID = String(userID!)

        var currentUser = Auth.auth().currentUser


//         Get sspecific document from current user
        let docRef = db.collection("users").document("bnf2s3RURUSV2Oecng9t")

        // Get data
        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")
            }
        }
    }

If you noticed, if I put manually "bnf2s3RURUSV2Oecng9t" it will access the data, but the point is to be able to know what ""bnf2s3RURUSV2Oecng9t" is so I can put it on that hard coded variable on top. My end goal is be able to get the first name of the current user :)

Answer 1

The problem is that your current authenticated user uid is not the same as the document uid. So normally if those ids where the same you would do something like this:

    private func getDocument() {
        //Get specific document from current user
        let docRef = Firestore.firestore()
            .collection("users")
            .document(Auth.auth().currentUser?.uid ?? "")

        // Get data
        docRef.getDocument { (document, error) in
            guard let document = document, document.exists else {
                print("Document does not exist")
                return
            }
            let dataDescription = document.data()
            print(dataDescription?["firstname"] ?? "")
        }
    }

But in your case you would need to do it like this, since those values are not the same.

    private func getDocument() {
         //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 }
                 print(firstname)
             }
         }
     }