Core Data Error: Cannot fetch without an NSManagedObjectContext in scope

Question

I am using XMPPFramework library in Swift which provides message history storage using Core Data. I am trying to request the archived messages from the storage using the following function:

func getChatHistory() {

    guard let context = xmppMessageStorage.mainThreadManagedObjectContext else {return}
    var entityDescription = NSEntityDescription.entity(forEntityName: "XMPPMessageArchiving_Message_CoreDataObject", in: context)
    var request = NSFetchRequest<NSFetchRequestResult>(entityName: "XMPPMessageArchiving_Message_CoreDataObject")
    request.entity = entityDescription
    do {
        var messages = try request.execute()
        print("Archived Messages: \n\(messages)")
    } catch let error {
        print("Error fetching chat history: \(error)")
    }

}

However, when I execute the function I receive the following error:

Error Domain=NSCocoaErrorDomain Code=134060 "A Core Data error occurred." UserInfo={message=Cannot fetch without an NSManagedObjectContext in scope}

I can't understand why this is happening as I am setting the context properly in my code. I would appreciate it if someone could help me understand what's wrong here.

Answer 1

Try to replace

request.entity = entityDescription
do {
  var messages = try request.execute()
  print("Archived Messages: \n\(messages)")
} catch let error {
  print("Error fetching chat history: \(error)")
}

With

do {
  let messages = try context.fetch(request)
  print("Archived Messages: \n\(messages)")
} catch {
  print("Error fetching chat history:", error)
}