CloudKit CKFetchRecordsOperation blocks - swift

Question

I'm fetching some cloud records using CKFetchRecordsOperation.
operation.perRecordCompletionBlock closure has a query to get some children records, but i noticed that operation.completionBlock closure is called before perRecordCompletionBlock completes his job. So, where should i call my completion closure which informs everything is done with that operation?
func getResidents(completion: #escaping (_ residents: [Resident]?, _ error: Error?) -> Void) {
var residents = [Resident]()
let recordNames = ["a56e39ad-9078-43b2-b699-5b9faa233f0d",
"e842daaa-3ff2-434b-9d50-3f14eb7e46d5",
"5cf075ad-d78a-4cea-872e-6b062781f14c",
"8e9fdbbb-cf06-486f-9fae-8be13abe2357",
"78b0cc19-9e33-4755-b199-7098fa319368",
"2d9bee21-d268-46cc-84e1-f7784495aac2",
"ae1da81b-bc1d-4e83-b145-c06882dc2203",
"3e13ed1e-e007-4ece-9a6c-8c09d638d6b3",
"78c224ab-e836-48c9-8c1c-f10bd4907457"
]
func getRecordIDs(names: [String]) -> [CKRecordID] {
var IDs = [CKRecordID]()
for name in names {
IDs.append(CKRecordID(recordName: name))
}
return IDs
}
let operation = CKFetchRecordsOperation(recordIDs: getRecordIDs(names: recordNames))
operation.perRecordCompletionBlock = { record, recordID, error in
if error != nil {
completion(nil, error)
} else {
if let record = record {
// Query debts (resident children)
let predicate = NSPredicate(format: "Resident = %#", record.recordID)
let query = CKQuery(recordType: Constants.RecordType.Debt, predicate: predicate)
self.publicCloudDB.perform(query, inZoneWith: nil) { records, error in
if error != nil {
// Retain the record IDs for failed fetches
completion(nil, error)
} else {
var debts = [Debt]()
if let debtRecords = records {
for item in debtRecords {
if let debt = Debt.parse(record: item) {
debts.append(debt)
}
}
}
if var resident = Resident.parse(record: record) {
resident.debts = debts
residents.append(resident)
print(resident)
}
}
}
}
}
}
operation.completionBlock = {
completion(residents, nil)
}
operation.allowsCellularAccess = true
operation.database = publicCloudDB
operation.start()
}