I was trying to use dataTaskPublisher in my project.

I already use dataTask successfully.

This is the code that I use it, it works when I use dataTask, but in this case with dataTaskPublisher it didn't get response from the print statements. Why is this happening ?

    var cancels: Set<AnyCancellable> = []
    
    let request = URLSessionHelper.getRequestWithUrl(endpointUrl: url, httpMethod: HTTPMethod.get, jsonBodyData: nil)
    let session = URLSession(configuration: URLSessionHelper.sessionConfiguration, delegate: SessionDelegate(), delegateQueue: nil)
    
    session.dataTaskPublisher(for: request)
        .map(\.data)
        .compactMap { String(data: $0, encoding:. utf8) }
        
        .sink { error in
                    print("error: \(error)")
                    // Cannot assign value of type 'Subscribers.Completion<Error>' to type 'Error?'
                 } receiveValue: { resutl in
                     print("resutl: \(resutl)")
                 }
        .store(in: &cancels)

CodePudding user response：

session is going immediately out-of-scope -- the Combine chain doesn't hold a strong reference to it.

You should store a reference to it as an instance variable on your class, which will prevent this problem.