public static bool IsWebSocketRequest(this RequestContext context)
{
if (!WebSocketHelpers.AreWebSocketsSupported)
{
return(false);
}
if (!context.IsUpgradableRequest)
{
return(false);
}
if (!string.Equals("GET", context.Request.Method, StringComparison.OrdinalIgnoreCase))
{
return(false);
}
// Connection: Upgrade (some odd clients send Upgrade,KeepAlive)
string connection = context.Request.Headers[HttpKnownHeaderNames.Connection];
if (connection == null || connection.IndexOf(HttpKnownHeaderNames.Upgrade, StringComparison.OrdinalIgnoreCase) < 0)
{
return(false);
}
// Upgrade: websocket
string upgrade = context.Request.Headers[HttpKnownHeaderNames.Upgrade];
if (!string.Equals(WebSocketHelpers.WebSocketUpgradeToken, upgrade, StringComparison.OrdinalIgnoreCase))
{
return(false);
}
// Sec-WebSocket-Version: 13
string version = context.Request.Headers[HttpKnownHeaderNames.SecWebSocketVersion];
if (!string.Equals(WebSocketConstants.SupportedProtocolVersion, version, StringComparison.OrdinalIgnoreCase))
{
return(false);
}
// Sec-WebSocket-Key: {base64string}
string key = context.Request.Headers[HttpKnownHeaderNames.SecWebSocketKey];
if (!WebSocketHelpers.IsValidWebSocketKey(key))
{
return(false);
}
return(true);
}
// Compare IsWebSocketRequest()
private static void ValidateWebSocketRequest(RequestContext context)
{
if (!WebSocketHelpers.AreWebSocketsSupported)
{
throw new NotSupportedException("WebSockets are not supported on this platform.");
}
if (!context.IsUpgradableRequest)
{
throw new InvalidOperationException("This request is not a valid upgrade request.");
}
if (!string.Equals("GET", context.Request.Method, StringComparison.OrdinalIgnoreCase))
{
throw new InvalidOperationException("This request is not a valid upgrade request; invalid verb: " + context.Request.Method);
}
// Connection: Upgrade (some odd clients send Upgrade,KeepAlive)
string connection = context.Request.Headers[HttpKnownHeaderNames.Connection];
if (connection == null || connection.IndexOf(HttpKnownHeaderNames.Upgrade, StringComparison.OrdinalIgnoreCase) < 0)
{
throw new InvalidOperationException("The Connection header is invalid: " + connection);
}
// Upgrade: websocket
string upgrade = context.Request.Headers[HttpKnownHeaderNames.Upgrade];
if (!string.Equals(WebSocketHelpers.WebSocketUpgradeToken, upgrade, StringComparison.OrdinalIgnoreCase))
{
throw new InvalidOperationException("The Upgrade header is invalid: " + upgrade);
}
// Sec-WebSocket-Version: 13
string version = context.Request.Headers[HttpKnownHeaderNames.SecWebSocketVersion];
if (!string.Equals(WebSocketConstants.SupportedProtocolVersion, version, StringComparison.OrdinalIgnoreCase))
{
throw new InvalidOperationException("The Sec-WebSocket-Version header is invalid or not supported: " + version);
}
// Sec-WebSocket-Key: {base64string}
string key = context.Request.Headers[HttpKnownHeaderNames.SecWebSocketKey];
if (!WebSocketHelpers.IsValidWebSocketKey(key))
{
throw new InvalidOperationException("The Sec-WebSocket-Key header is invalid: " + upgrade);
}
}
