/// <summary>
/// Handler for pre-login request
/// </summary>
public override TDSMessageCollection OnPreLoginRequest(ITDSServerSession session, TDSMessage request)
{
// Delegate to the base class
TDSMessageCollection response = base.OnPreLoginRequest(session, request);
// Check if arguments are of the routing server
if (Arguments is RoutingTDSServerArguments)
{
// Cast to routing server arguments
RoutingTDSServerArguments serverArguments = Arguments as RoutingTDSServerArguments;
// Check if routing is configured during login
if (serverArguments.RouteOnPacket == TDSMessageType.TDS7Login)
{
// Check if pre-login response is contained inside the first message
if (response.Count > 0 && response[0].Any(t => t is TDSPreLoginToken))
{
// Find the first prelogin token
TDSPreLoginToken preLoginResponse = (TDSPreLoginToken)response[0].Where(t => t is TDSPreLoginToken).First();
// Inflate pre-login request from the message
TDSPreLoginToken preLoginRequest = request[0] as TDSPreLoginToken;
// Update MARS with the requested value
preLoginResponse.IsMARS = preLoginRequest.IsMARS;
}
}
}
return(response);
}
/// <summary>
/// Handler for login request
/// </summary>
public override TDSMessageCollection OnLogin7Request(ITDSServerSession session, TDSMessage request)
{
// Inflate login7 request from the message
TDSLogin7Token loginRequest = request[0] as TDSLogin7Token;
// Check if arguments are of the routing server
if (Arguments is RoutingTDSServerArguments)
{
// Cast to routing server arguments
RoutingTDSServerArguments ServerArguments = Arguments as RoutingTDSServerArguments;
// Check filter
if (ServerArguments.RequireReadOnly && (loginRequest.TypeFlags.ReadOnlyIntent != TDSLogin7TypeFlagsReadOnlyIntent.ReadOnly))
{
// Log request
TDSUtilities.Log(Arguments.Log, "Request", loginRequest);
// Prepare ERROR token with the denial details
TDSErrorToken errorToken = new TDSErrorToken(18456, 1, 14, "Received application intent: " + loginRequest.TypeFlags.ReadOnlyIntent.ToString(), Arguments.ServerName);
// Log response
TDSUtilities.Log(Arguments.Log, "Response", errorToken);
// Serialize the error token into the response packet
TDSMessage responseMessage = new TDSMessage(TDSMessageType.Response, errorToken);
// Prepare ERROR token for the final decision
errorToken = new TDSErrorToken(18456, 1, 14, "Read-Only application intent is required for routing", Arguments.ServerName);
// Log response
TDSUtilities.Log(Arguments.Log, "Response", errorToken);
// Serialize the error token into the response packet
responseMessage.Add(errorToken);
// Create DONE token
TDSDoneToken doneToken = new TDSDoneToken(TDSDoneTokenStatusType.Final | TDSDoneTokenStatusType.Error);
// Log response
TDSUtilities.Log(Arguments.Log, "Response", doneToken);
// Serialize DONE token into the response packet
responseMessage.Add(doneToken);
// Return a single message in the collection
return(new TDSMessageCollection(responseMessage));
}
}
// Delegate to the base class
return(base.OnLogin7Request(session, request));
}
/// <summary>
/// It is called when SQL batch request arrives
/// </summary>
/// <param name="message">TDS message recieved</param>
/// <returns>TDS message to respond with</returns>
public override TDSMessageCollection OnSQLBatchRequest(ITDSServerSession session, TDSMessage request)
{
// Delegate to the base class to produce the response first
TDSMessageCollection batchResponse = base.OnSQLBatchRequest(session, request);
// Check if arguments are of routing server
if (Arguments is RoutingTDSServerArguments)
{
// Cast to routing server arguments
RoutingTDSServerArguments ServerArguments = Arguments as RoutingTDSServerArguments;
// Check routing condition
if (ServerArguments.RouteOnPacket == TDSMessageType.SQLBatch)
{
// Construct routing token
TDSPacketToken routingToken = CreateRoutingToken();
// Log response
TDSUtilities.Log(Arguments.Log, "Response", routingToken);
// Insert the routing token at the beginning of the response
batchResponse[0].Insert(0, routingToken);
}
else
{
// Get the first response message
TDSMessage responseMessage = batchResponse[0];
// Reset the content of the first message
responseMessage.Clear();
// Prepare ERROR token with the denial details
responseMessage.Add(new TDSErrorToken(11111, 1, 14, "Client should have been routed by now", Arguments.ServerName));
// Log response
TDSUtilities.Log(Arguments.Log, "Response", responseMessage[0]);
// Prepare DONE token
responseMessage.Add(new TDSDoneToken(TDSDoneTokenStatusType.Final | TDSDoneTokenStatusType.Error));
// Log response
TDSUtilities.Log(Arguments.Log, "Response", responseMessage[1]);
}
}
// Register only one message with the collection
return(batchResponse);
}
/// <summary>
/// Create a new instance of the routing token that instructs client according to the routing destination URL
/// </summary>
protected TDSPacketToken CreateRoutingToken()
{
// Cast to routing server arguments
RoutingTDSServerArguments ServerArguments = Arguments as RoutingTDSServerArguments;
// Construct routing token value
TDSRoutingEnvChangeTokenValue routingInfo = new TDSRoutingEnvChangeTokenValue();
// Read the values and populate routing info
routingInfo.Protocol = (TDSRoutingEnvChangeTokenValueType)ServerArguments.RoutingProtocol;
routingInfo.ProtocolProperty = ServerArguments.RoutingTCPPort;
routingInfo.AlternateServer = ServerArguments.RoutingTCPHost;
// Construct routing token
return(new TDSEnvChangeToken(TDSEnvChangeTokenType.Routing, routingInfo));
}
/// <summary>
/// Complete login sequence
/// </summary>
protected override TDSMessageCollection OnAuthenticationCompleted(ITDSServerSession session)
{
// Delegate to the base class
TDSMessageCollection responseMessageCollection = base.OnAuthenticationCompleted(session);
// Check if arguments are of routing server
if (Arguments is RoutingTDSServerArguments)
{
// Cast to routing server arguments
RoutingTDSServerArguments serverArguments = Arguments as RoutingTDSServerArguments;
// Check routing condition
if (serverArguments.RouteOnPacket == TDSMessageType.TDS7Login)
{
// Construct routing token
TDSPacketToken routingToken = CreateRoutingToken();
// Log response
TDSUtilities.Log(Arguments.Log, "Response", routingToken);
// Get the first message
TDSMessage targetMessage = responseMessageCollection[0];
// Index at which to insert the routing token
int insertIndex = targetMessage.Count - 1;
// VSTS# 1021027 - Read-Only Routing yields TDS protocol error
// Resolution: Send TDS FeatureExtAct token before TDS ENVCHANGE token with routing information
TDSPacketToken featureExtAckToken = targetMessage.Find(t => t is TDSFeatureExtAckToken);
// Check if found
if (featureExtAckToken != null)
{
// Find token position
insertIndex = targetMessage.IndexOf(featureExtAckToken);
}
// Insert right before the done token
targetMessage.Insert(insertIndex, routingToken);
}
}
return(responseMessageCollection);
}
/// <summary>
/// Initialization constructor
/// </summary>
public RoutingTDSServer(RoutingTDSServerArguments arguments) :
base(arguments)
{
}
/// <summary>
/// Initialization constructor
/// </summary>
public RoutingTDSServer(RoutingTDSServerArguments arguments) :
base(arguments)
{
}
