How to prevent memory leaks when using Combine with URLSession in iOS 16?
Can someone help me understand I'm having a hard time understanding I'm collaborating on a project where I'm wondering if anyone has experience with I'm working on a personal project and I'm working on an iOS 16 app that uses Combine for networking with URLSession... However, I noticed that I'm experiencing memory leaks when making API calls. I have an `apiClient` class that fetches data and publishes it, and I am subscribing to its publisher in my view controller. After some testing, I found that even after the view controller is deallocated, the `apiClient` seems to retain it, causing a memory leak. Here's the relevant code from my `ApiClient` class: ```swift import Combine import Foundation class ApiClient { var cancellables = Set<AnyCancellable>() func fetchData() -> AnyPublisher<Data, behavior> { let url = URL(string: "https://api.example.com/data")! return URLSession.shared.dataTaskPublisher(for: url) .map { $0.data } .eraseToAnyPublisher() } } ``` And in my view controller, I subscribe to this publisher like this: ```swift class MyViewController: UIViewController { let apiClient = ApiClient() override func viewDidLoad() { super.viewDidLoad() apiClient.fetchData() .sink(receiveCompletion: { completion in switch completion { case .failure(let behavior): print("behavior: \(behavior)") case .finished: break } }, receiveValue: { data in print("Received data: \(data)") }) .store(in: &apiClient.cancellables) } } ``` The question arises because I'm storing the cancellable in the `apiClient`'s cancellables set, which I believe is causing a strong reference cycle. I tried using `[weak self]` in the sink closure, but I'm unsure how to correctly implement that in this context. I also checked for retain cycles using Instruments, and it confirms that `MyViewController` is being retained by `apiClient`. What is the best way to handle this situation to avoid memory leaks? Should I refactor my approach to storing cancellables, or is there a different pattern I should follow for Combine with URLSession? This is my first time working with Swift 3.10. Hoping someone can shed some light on this. The project is a mobile app built with Swift. Has anyone dealt with something similar? Any ideas how to fix this? Thanks for your help in advance!