struct Postman: Codable {
    let valid: Bool
}

enum MyError: Error {
    case invalidServerResponse
}





let url = URL(string: "https://postman-echo.com/time/valid?timestamp=2016-10-10")!


let cancellable = URLSession.shared.dataTaskPublisher(for: url)
    .tryMap { data, response -> Data in
        guard let httpResponse = response as? HTTPURLResponse,
              httpResponse.statusCode == 200 else {
            throw MyError.invalidServerResponse
        }
        return data
    }
    .decode(type: Postman.self, decoder: JSONDecoder())
    .sink(receiveCompletion: { completion in
        print(".sink() received the completion", String(describing: completion))
        switch completion {
            case .finished:
                break
            case .failure(let error):
                print("received error: ", error)
        }
    }, receiveValue: { value in
        print(".sink() received \(value)")
    })