protected bool AsyncFetch <T>(Uri requestUri, Func <Uri, T> fetcher, out RemoteServerException remoteException)
{
if (null == requestUri)
{
remoteException = null;
return(true);
}
lock (_lock)
{
RemoteResponse response;
var key = new RequestKey(typeof(T), requestUri);
if (_responses.TryGetValue(key, out response))
{
remoteException = response.Exception;
return(true);
}
remoteException = null;
if (!_fetchRequests.Add(key))
{
return(false);
}
}
ActionUtil.RunAsync(() => FetchAndStore(requestUri, fetcher));
return(false);
}
private void FetchAndStore <T>(Uri requestUri, Func <Uri, T> fetcher)
{
var key = new RequestKey(typeof(T), requestUri);
try
{
var data = fetcher(requestUri);
lock (_lock)
{
_responses[key] = new RemoteResponse(data, null);
}
}
catch (Exception exception)
{
RemoteServerException remoteException = exception as RemoteServerException;
// ReSharper disable once ConvertIfStatementToNullCoalescingExpression
if (null == remoteException)
{
remoteException = new RemoteServerException(
Resources.RemoteSession_FetchContents_There_was_an_error_communicating_with_the_server__
+ exception.Message, exception);
}
lock (_lock)
{
_responses[key] = new RemoteResponse(null, remoteException);
}
}
FireContentsAvailable();
}
public abstract bool AsyncFetchContents(RemoteUrl remoteUrl, out RemoteServerException remoteException);
public RemoteResponse(object data, RemoteServerException exception)
{
Data = data;
Exception = exception;
}
