/// <inheritdoc />
public FtpCommandSelection?Create(FtpCommandHandlerContext context)
{
var result = ActivateCommandHandler(context);
if (result != null)
{
ActivateProperty(result.Handler, context);
}
return(result);
}
private FtpCommandSelection?ActivateCommandHandler(FtpCommandHandlerContext context)
{
if (!_nameToHandlerInfo.TryGetValue(context.FtpContext.Command.Name, out var handlerInfo))
{
return(null);
}
if (_commandHandlers.TryGetValue(handlerInfo.Type, out var handler))
{
return(new FtpCommandSelection(handler, handlerInfo));
}
#pragma warning disable 612
if (handlerInfo is IFtpCommandHandlerInstanceInformation handlerInstanceInfo)
#pragma warning restore 612
{
handler = handlerInstanceInfo.Instance;
}
else
{
handler = (IFtpCommandHandler)ActivatorUtilities.CreateInstance(
_serviceProvider,
handlerInfo.Type);
}
IFtpCommandInformation commandInformation = handlerInfo;
if (handlerInfo.IsExtensible && handler is IFtpCommandHandlerExtensionHost extensionHost)
{
var extensions = ActivateExtensions(context, handlerInfo).ToList();
var hostExtensions = extensions.ToDictionary(
x => x.Item2.Name,
x => Tuple.Create(x.Item1, x.Item2),
StringComparer.OrdinalIgnoreCase);
extensionHost.Extensions = hostExtensions.ToDictionary(
x => x.Key,
x => x.Value.Item1);
var argument = FtpCommand.Parse(context.FtpContext.Command.Argument);
if (hostExtensions.TryGetValue(argument.Name, out var hostExtensionDictValue))
{
commandInformation = hostExtensionDictValue.Item2;
}
}
_commandHandlers.Add(handlerInfo.Type, handler);
return(new FtpCommandSelection(handler, commandInformation));
}
/// <inheritdoc />
public async Task DispatchAsync(FtpContext context, CancellationToken cancellationToken)
{
var loginStateMachine =
_loginStateMachine
?? throw new InvalidOperationException("Login state machine not initialized.");
var commandHandlerContext = new FtpCommandHandlerContext(context);
var result = _commandActivator.Create(commandHandlerContext);
if (result == null)
{
await SendResponseAsync(
new FtpResponse(500, T("Syntax error, command unrecognized.")),
cancellationToken)
.ConfigureAwait(false);
return;
}
var handler = result.Handler;
var isLoginRequired = result.Information.IsLoginRequired;
if (isLoginRequired && loginStateMachine.Status != SecurityStatus.Authorized)
{
await SendResponseAsync(
new FtpResponse(530, T("Not logged in.")),
cancellationToken)
.ConfigureAwait(false);
return;
}
if (result.Information.IsAbortable)
{
await ExecuteBackgroundCommandAsync(context, handler, cancellationToken)
.ConfigureAwait(false);
}
else
{
var executionContext = new FtpExecutionContext(context, handler, cancellationToken);
await _executionDelegate(executionContext)
.ConfigureAwait(false);
}
}
private FtpCommandSelection ActivateCommandHandler([NotNull] FtpCommandHandlerContext context)
{
if (!_nameToHandlerInfo.TryGetValue(context.FtpContext.Command.Name, out var handlerInfo))
{
return(null);
}
if (_commandHandlers.TryGetValue(handlerInfo.Type, out var handler))
{
return(new FtpCommandSelection(handler, handlerInfo));
}
#pragma warning disable 612
if (handlerInfo is IFtpCommandHandlerInstanceInformation handlerInstanceInfo)
#pragma warning restore 612
{
handler = handlerInstanceInfo.Instance;
}
else
{
handler = (IFtpCommandHandler)ActivatorUtilities.CreateInstance(
_serviceProvider,
handlerInfo.Type);
}
if (handler is IFtpCommandHandlerExtensionHost extensionHost)
{
var extensions = ActivateExtensions(context, handlerInfo).ToList();
extensionHost.Extensions = extensions.ToDictionary(
x => x.Item2.Name,
x => x.Item1,
StringComparer.OrdinalIgnoreCase);
}
_commandHandlers.Add(handlerInfo.Type, handler);
return(new FtpCommandSelection(handler, handlerInfo));
}
private IEnumerable <Tuple <IFtpCommandHandlerExtension, IFtpCommandHandlerExtensionInformation> > ActivateExtensions(
FtpCommandHandlerContext context,
IFtpCommandHandlerInformation handlerInfo)
{
var extensionInfos = _hostToExtensionInfo[handlerInfo.Name].ToList();
var typesToInfos = extensionInfos.ToLookup(x => x.Type);
var extensionTypes = extensionInfos.Select(x => x.Type).Distinct();
foreach (var extensionType in extensionTypes)
{
var extensionInfo = typesToInfos[extensionType].First();
if (!_commandHandlerExtensions.TryGetValue(extensionType, out var extension))
{
#pragma warning disable 612
if (extensionInfo is IFtpCommandHandlerExtensionInstanceInformation extensionInstanceInfo)
#pragma warning restore 612
{
extension = extensionInstanceInfo.Instance;
}
else
{
extension = (IFtpCommandHandlerExtension)ActivatorUtilities.CreateInstance(
_serviceProvider,
extensionType);
}
ActivateProperty(extension, context);
extension.InitializeConnectionData();
_commandHandlerExtensions.Add(extensionType, extension);
}
yield return(Tuple.Create(extension, extensionInfo));
}
}
private void ActivateProperty(object handler, FtpCommandHandlerContext context)
{
var property = GetCommandContextProperty(handler.GetType());
property?.SetValue(handler, context);
}
