Example for WKURLSchemeHandler implementation to replace custom url scheme with "https"

MySchemeHandler.swift

class MySchemeHandler: NSObject, WKURLSchemeHandler {
    func webView(_ webView: WKWebView, start urlSchemeTask: WKURLSchemeTask) {
        print("started for \(urlSchemeTask.request.url?.absoluteString)")
        guard let url = urlSchemeTask.request.url else { return }
        var components = URLComponents(url: url, resolvingAgainstBaseURL: true)
        components?.scheme = "https"
        guard let finalUrl = components?.url else {  return }
        print("proxy to \(finalUrl.absoluteString)")
        let task = URLSession.shared.dataTask(with: URLRequest(url: finalUrl)) { receivedData, urlresponse, error in
            guard let response = urlresponse, let data = receivedData else { urlSchemeTask.didFinish(); return }
            urlSchemeTask.didReceive(response)
            urlSchemeTask.didReceive(data)
            urlSchemeTask.didFinish()
            print("didFinish \(urlSchemeTask.request.url?.absoluteString)")
        }
        task.resume()
    }

    func webView(_ webView: WKWebView, stop urlSchemeTask: WKURLSchemeTask) {
        print("stopped")
    }
}