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Question

I have a firestore function which adds data to a collection:

func blockUser(userId: String) {
    Firestore.firestore().collection("blocked").document(Auth.auth().currentUser!.uid).collection("userBlocked").document(userId).setData([:])
}

Works fine, creates a structure like (as expected):

and in the userBlocked collection its adds a user id which has been blocked like so:

Im trying to retrieve the userBlocked with the following:

    Firestore.firestore().collection("blocked").document(Auth.auth().currentUser!.uid).collection("userBlocked").getDocuments{(snapshot,error) in
        guard let snap = snapshot else {
            print("error getting blocked users")
            return
        }
        //var blockedUsers = [User]()
        for document in snap.documents {
            let dict = document
            print("printing blocked user - \(dict)")
        }
    }

In the logs im getting:

printing blocked user - <FIRQueryDocumentSnapshot: 0x6000015c3610>

Im trying to retrieve each blocked user? but can't seem to get each user id, it should be getting back d8j5fU8rinUcAEZyNZ5qAIzoa1j2

Answer 1

You're going to have to write code to get the document data out of the QuerySnapshot that was delivered to your callback. I suggest starting with the documentation .

In your code, snap is a QuerySnapshot , and document is a QueryDocumentSnapshot . You can see from the linked API docs that QueryDocumentSnapshot has a data() method that gets you the document data as a dictionary.

However, you didn't write any fields to the document, so the dictionary will be empty. If you want the ID of the document, you can use document.documentID .