ios-networking

To handle a 401 token refresh in URLSession with async/await, implement an interceptor that catches the unauthorized status, refreshes the token, and retries the request. This structured concurrency approach safely manages transient auth failures without completion handler chaining.

The best way to validate HTTP status codes in an iOS API client is to inspect the HTTP response immediately after the async URLSession data fetch, throw a typed error for invalid statuses, and only proceed to decode the Codable response if validation passes.

NWPathMonitor reachability works with structured concurrency by continuously monitoring network availability via Network.framework, allowing your API client to adaptively pause or alter request behavior when connectivity drops, ensuring network requests respect current path status.

You can use AsyncSequence for cursor and offset pagination in Swift networking by wrapping paginated URLSession requests, allowing you to iterate through pages sequentially while honoring Task cancellation during the data fetching process.

To implement exponential backoff with cancellation awareness, use Swift's Task.sleep inside a retry loop for transient failures, checking Task.isCancelled before each retry attempt to ensure the backoff process stops immediately when the network task is cancelled.

You should use download(for:) instead of standard URLSession data tasks when fetching large files, as the async/await download API streams data directly to disk, conserving memory while still respecting Task cancellation and HTTP response validation.