A dummy function which shows the usage of callbackFlow

callbackFlow.kt

    fun myFunction(id: String): Flow<MyObject> =
        callbackFlow {
            firestoreEventListener = firestore.collection(MY_COLLECTION_PATH)
                .document(id)
                .addSnapshotListener { snapshot, _ ->
                    if (snapshot != null && snapshot.exists()) {
                        if (!snapshot.metadata.isFromCache) {
                            snapshot.toObject(MyFirestoreObject::class.java)?.let {
                                it.id = id
                                trySend(it)
                            }
                        }
                    }
                }

            awaitClose {
                unsubscribeFirestore()
            }
        }