/// <summary>
/// Closes the WebSocket connection using the close handshake defined in the
/// WebSocket protocol specification section 7.
/// </summary>
/// <param name="closeStatus">Indicates the reason for closing the WebSocket connection.</param>
/// <param name="statusDescription">Specifies a human readable explanation as to why the connection is closed.</param>
/// <param name="cancellationToken">The token that can be used to propagate notification that operations should be canceled.</param>
/// <returns>Returns System.Threading.Tasks.Task.</returns>
public Task CloseAsync(CloseCodeStatus closeStatus, string statusDescription, CancellationToken cancellationToken)
{
// Create a new task.
return(Task.Factory.StartNew(() =>
{
try
{
// Check can be closed.
var msg = _readyState.CheckIfClosable() ?? closeStatus.CheckIfValidCloseParameters(statusDescription);
if (!String.IsNullOrEmpty(msg))
{
return;
}
// If cancellation has not been requested.
if (!cancellationToken.IsCancellationRequested)
{
// If no status code.
if (closeStatus.IsNoStatusCode())
{
// Close the connection.
Close(new CloseEventArgs(), true, true);
return;
}
// Close the connection.
var send = !closeStatus.IsReserved();
Close(new CloseEventArgs(closeStatus, statusDescription), send, send);
}
}
catch { }
}, cancellationToken));
}
/// <summary>
/// Is reserved.
/// </summary>
/// <param name="code">The CloseCodeStatus code.</param>
/// <returns>True if reserved.</returns>
public static bool IsReserved(this CloseCodeStatus code)
{
return(code == CloseCodeStatus.Undefined ||
code == CloseCodeStatus.NoStatusReceived ||
code == CloseCodeStatus.AbnormalClosure ||
code == CloseCodeStatus.TLSHandshake);
}
/// <summary>
/// Check if valid close parameters.
/// </summary>
/// <param name="code">The code.</param>
/// <param name="reason">The reason.</param>
/// <returns>The message.</returns>
public static string CheckIfValidCloseParameters(this CloseCodeStatus code, string reason)
{
return(code.IsNoStatusCode() && !reason.IsNullOrEmpty()
? "NoStatusCode cannot have a reason."
: !reason.IsNullOrEmpty() && Encoding.UTF8.GetBytes(reason).Length > 123
? "A reason has greater than the allowable max size."
: null);
}
/// <summary>
/// Get a close code status messsage.
/// </summary>
/// <param name="code">Close code status.</param>
/// <returns>The message.</returns>
public static string GetMessage(this CloseCodeStatus code)
{
return(code == CloseCodeStatus.ProtocolError
? "A WebSocket protocol error has occurred."
: code == CloseCodeStatus.UnsupportedData
? "An incorrect data has been received."
: code == CloseCodeStatus.AbnormalClosure
? "An exception has occurred."
: code == CloseCodeStatus.InvalidFramePayloadData
? "An inconsistent data has been received."
: code == CloseCodeStatus.PolicyViolation
? "A policy violation has occurred."
: code == CloseCodeStatus.MessageTooBig
? "A too big data has been received."
: code == CloseCodeStatus.MandatoryExtension
? "WebSocket client didn't receive expected extension(s)."
: code == CloseCodeStatus.InternalServerError
? "WebSocket server got an internal error."
: code == CloseCodeStatus.TLSHandshake
? "An error has occurred while handshaking."
: String.Empty);
}
/// <summary>
/// Close connection.
/// </summary>
/// <param name="code">The close code.</param>
/// <param name="reason">The message.</param>
internal CloseEventArgs(CloseCodeStatus code, string reason)
: this((ushort)code, reason)
{
}
/// <summary>
/// Close connection.
/// </summary>
/// <param name="code">The close code.</param>
internal CloseEventArgs(CloseCodeStatus code)
: this((ushort)code)
{
}
/// <summary>
/// Process unsupported frame.
/// </summary>
/// <param name="frame">The frame.</param>
/// <param name="code">The close code.</param>
/// <param name="reason">The invalid description.</param>
/// <returns>Returns false.</returns>
private bool ProcessUnsupportedFrame(Frame frame, CloseCodeStatus code, string reason)
{
ProcessException(new WebSocketException(code, reason), null);
return(false);
}
/// <summary>
/// Is no status received.
/// </summary>
/// <param name="code">The code.</param>
/// <returns>True if no status; else false.</returns>
public static bool IsNoStatusCode(this CloseCodeStatus code)
{
return(code == CloseCodeStatus.NoStatusReceived);
}
/// <summary>
/// The exception that is thrown when a <see cref="WebSocket"/> gets a fatal error.
/// </summary>
/// <param name="code">The close code status.</param>
public WebSocketException(CloseCodeStatus code)
: this(code, null, null)
{
}
/// <summary>
/// The exception that is thrown when a <see cref="WebSocket"/> gets a fatal error.
/// </summary>
/// <param name="code">The close code status.</param>
/// <param name="message">The message.</param>
/// <param name="innerException">Inner exception.</param>
public WebSocketException(CloseCodeStatus code, string message, Exception innerException)
: base(message ?? code.GetMessage(), innerException)
{
_code = code;
}
/// <summary>
/// The exception that is thrown when a <see cref="WebSocket"/> gets a fatal error.
/// </summary>
/// <param name="code">The close code status.</param>
/// <param name="message">The message.</param>
public WebSocketException(CloseCodeStatus code, string message)
: this(code, message, null)
{
}
/// <summary>
/// The exception that is thrown when a <see cref="WebSocket"/> gets a fatal error.
/// </summary>
/// <param name="code">The close code status.</param>
/// <param name="innerException">Inner exception.</param>
public WebSocketException(CloseCodeStatus code, Exception innerException)
: this(code, null, innerException)
{
}