private static async Task <string> ResolveShortener(Uri uri, CancellationToken cancellationToken)
{
if (UrlShorteners.All(s => !uri.Host.EndsWith(s)))
{
return(null);
}
var response = await client.GetAsync(uri, cancellationToken);
var location = response.Headers.Location;
return(location?.OriginalString);
}
/// <summary>
/// Updates
/// </summary>
/// <returns></returns>
private static async Task UpdateUnderlyingURLAsync(CancellationToken cancellationToken)
{
while (true)
{
var url = UnderlyingTargetURL;
var uri = new Uri(url);
foreach (var service in JumpPages)
{
if (!url.StartsWith(service.Key))
{
continue;
}
var queryStringValues = HttpUtility.ParseQueryString(uri.Query);
var underlyingUrl = queryStringValues["url"];
if (underlyingUrl != null)
{
UnderlyingTargetURL = underlyingUrl;
}
}
if (UnderlyingTargetURL != url)
{
continue;
}
if (UrlShorteners.Contains(uri.Host))
{
var clientHandler = new HttpClientHandler {
AllowAutoRedirect = false
};
var client = new HttpClient(clientHandler);
try
{
var response = await client.GetAsync(url, cancellationToken);
var location = response.Headers.Location;
if (location != null)
{
UnderlyingTargetURL = location.OriginalString;
continue;
}
}
catch (TaskCanceledException)
{
// TaskCanceledException occurs when the CancellationToken is triggered before the request completes
// In this case, skip the lookup to avoid poor user experience
}
}
break;
}
}
