How do I parse and respect Retry-After headers in Swift?

To parse and respect Retry-After headers in Swift, you can utilize URLSession to perform network requests and handle HTTP responses effectively. The Retry-After header indicates how long to wait before making a new request after a rate limit has been reached.

        // Example code to handle Retry-After headers in Swift
        let url = URL(string: "https://api.example.com/data")!
        var request = URLRequest(url: url)
        
        let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
            if let httpResponse = response as? HTTPURLResponse {
                if httpResponse.statusCode == 429 { // Too Many Requests
                    if let retryAfter = httpResponse.value(forHTTPHeaderField: "Retry-After") {
                        let secondsToWait = Double(retryAfter) ?? 60.0 // Default to 60 seconds
                        print("Rate limit exceeded. Retry after: \(secondsToWait) seconds.")
                        DispatchQueue.global().asyncAfter(deadline: .now() + secondsToWait) {
                            // Retry the request here...
                        }
                    }
                } else {
                    // Handle other responses
                }
            }
        }
        
        task.resume()