add/overwrite field of type array in Firestore

Question

I want to add a field of type array inside a collection.

if the field doesn't exist create it. if it exists overwrite it with the new array value.

the field should be called macAddress and it's of type array of String

I have tried the following:

val macInput = setting_mac_text.text.toString()
            val macArray = macInput.split(",")
            val macList = Arrays.asList(macArray)
            val data =
                hashMapOf(Pair(FirebaseConstants.USER_MAC_ADDRESS, macArray))
            //save it in firebase
            db.collection(FirebaseConstants.ORGANIZATION)
                .document(orgID + ".${FirebaseConstants.USER_MAC_ADDRESS}")
                .set(FieldValue.arrayUnion(macList))
                .addOnCompleteListener { task ->
                    if (task.isSuccessful) {
                        Log.d(TAG, "successfully inserted")
                    } else {
                        Log.d(TAG, " failed ${task.exception}")
                    }
                }

also tried to insert the list itself and hash map like this

val data = hashMapOf(Pair(FirebaseConstants.USER_MAC_ADDRESS, macArray))
db.collection(FirebaseConstants.ORGANIZATION)
                .document(orgID)
                .set(data))

but it keeps giving me java.lang.IllegalArgumentException: Invalid data. Nested arrays are not supported

what am I doing wrong here?

Answer 1

To overwrite an array, you would simply call the set method and have the merge option set to true:

try {
  const query = await DatabaseService.queryBuilder({
    collection: CollectionName,
  });

  return await query
    .doc(insuranceId)
    .set(
      { DOCUMENT_PROPERTY_HERE: ARRAY_HERE },
      { merge: true }
    );
} catch (exception) {
  return Promise.reject(exception);
}