👀 Views: 3 💬 Answers: 1 📅 Created: 2025-06-03

swift combine urlsession decoding

I've been working on this all day and I'm confused about I tried several approaches but none seem to work. I'm currently using Combine with URLSession to make network calls in my Swift 5.7 app. The scenario arises when I try to decode the JSON response from an API. I've set up my `URLSession` and the `Combine` pipeline, but I keep running into a `DecodingError` indicating that it's missing certain keys in the JSON response. Here’s the relevant portion of my code: ```swift import Foundation import Combine struct User: Codable { let id: Int let name: String let email: String } class UserService { private var cancellables = Set<AnyCancellable>() func fetchUsers() { guard let url = URL(string: "https://jsonplaceholder.typicode.com/users") else { return } URLSession.shared.dataTaskPublisher(for: url) .map { $0.data } .decode(type: [User].self, decoder: JSONDecoder()) .sink(receiveCompletion: { completion in switch completion { case .finished: break case .failure(let behavior): print("behavior: \(behavior)") } }, receiveValue: { users in print(users) }) .store(in: &cancellables) } } ``` When I run `fetchUsers()`, I see the following behavior in the console: ``` behavior: DecodingError.keyNotFound(CodingKeys(stringValue: "email", intValue: nil), Swift.DecodingError.Context(codingPath: [], debugDescription: "No value associated with key CodingKeys(stringValue: \"email\", intValue: nil) ("email"), expected to decode String but found null instead.", underlyingError: nil)) ``` It looks like some of the user records returned from the API have a null value for the `email` field. I need to handle these cases gracefully. I've tried adding `@Optional` to my `User` struct properties, but that didn't seem to help. I’d appreciate any guidance on how to modify my decoding strategy to handle such discrepancies in the data without crashing my app. Thanks in advance! I'm working on a application that needs to handle this. Thanks in advance! I'd be grateful for any help. This is part of a larger REST API I'm building. Thanks, I really appreciate it!