/// <summary>
/// Initiates an asynchronous request/response transmission with a specific timeout.
/// </summary>
/// <param name="message">The request message.</param>
/// <param name="timeout">The maximum time to wait for a response.</param>
/// <param name="callback">The <see cref="AsyncCallback" /> delegate to be called when the operation completes (or <c>null</c>).</param>
/// <param name="state">The application specific state (or <c>null</c>).</param>
/// <returns>The <see cref="IAsyncResult" /> instance to be used to track the status of the operation.</returns>
/// <remarks>
/// <note>
/// All successful calls to <see cref="BeginRequest(Message,TimeSpan,AsyncCallback,object)" /> must
/// eventually be followed by a call to <see cref="EndRequest" />.
/// </note>
/// </remarks>
public IAsyncResult BeginRequest(Message message, TimeSpan timeout, AsyncCallback callback, object state)
{
using (TimedLock.Lock(this))
{
ThrowIfDisposedOrNotOpen();
ServiceModelHelper.ValidateTimeout(timeout);
try
{
using (MemoryStream ms = new MemoryStream(payloadEstimator.EstimateNextBufferSize()))
{
WcfEnvelopeMsg requestMsg = new WcfEnvelopeMsg();
encoder.WriteMessage(message, ms);
payloadEstimator.LastPayloadSize((int)ms.Length);
requestMsg.Payload = new ArraySegment <byte>(ms.GetBuffer(), 0, (int)ms.Length);
return(ChannelHost.Router.BeginQuery(ep, requestMsg, callback, state));
}
}
catch (Exception e)
{
throw ServiceModelHelper.GetCommunicationException(e);
}
}
}
/// <summary>
/// Intitiates an asynchronous operation to send a reply to the context request.
/// </summary>
/// <param name="context">The <see cref="LillTekRequestContext" /> context.</param>
/// <param name="message">The reply <see cref="Message" />.</param>
/// <param name="callback">The <see cref="AsyncCallback" /> delegate to be called when the operation completes (or <c>null</c>).</param>
/// <param name="state">Application defined state (or <c>null</c>).</param>
/// <returns>The <see cref="IAsyncResult" /> to be used to track the status of the operation.</returns>
/// <remarks>
/// <note>
/// Every successful call to <see cref="BeginReply(LillTekRequestContext,Message,AsyncCallback,object)" /> must eventually be followed by
/// a call to <see cref="EndReply" />.
/// </note>
/// </remarks>
public IAsyncResult BeginReply(LillTekRequestContext context, Message message, AsyncCallback callback, object state)
{
AsyncResult arReply;
// This operation is inherently asynchronous at the LillTek Messaging level
// so we'll complete the operation immediately.
using (MemoryStream ms = new MemoryStream(payloadEstimator.EstimateNextBufferSize()))
{
WcfEnvelopeMsg replyMsg = new WcfEnvelopeMsg();
encoder.WriteMessage(message, ms);
payloadEstimator.LastPayloadSize((int)ms.Length);
replyMsg.Payload = new ArraySegment <byte>(ms.GetBuffer(), 0, (int)ms.Length);
using (TimedLock.Lock(this))
{
if (pendingRequests.ContainsKey(context.MsgRequestContext.SessionID))
{
pendingRequests.Remove(context.MsgRequestContext.SessionID);
}
context.MsgRequestContext.Reply(replyMsg);
}
}
arReply = new AsyncResult(null, callback, state);
arReply.Started(ServiceModelHelper.AsyncTrace);
arReply.Notify();
return(arReply);
}
//---------------------------------------------------------------------
// DuplexSession event handlers
/// <summary>
/// Handles messages received on the underlying LillTek <see cref="DuplexSession" /> session.
/// </summary>
/// <param name="session">The <see cref="DuplexSession" />.</param>
/// <param name="msg">The received LillTek message.</param>
private void OnSessionReceive(DuplexSession session, Msg msg)
{
WcfEnvelopeMsg envelopeMsg = msg as WcfEnvelopeMsg;
if (envelopeMsg == null)
{
return; // Discard anything but WCF messages
}
Enqueue(listener.DecodeMessage(envelopeMsg));
}
/// <summary>
/// Decodes the WCF <see cref="Message" /> encapsulated within a LillTek <see cref="WcfEnvelopeMsg" />.
/// </summary>
/// <param name="msg">The LillTek message.</param>
/// <returns>The WCF <see cref="Message" />.</returns>
/// <exception cref="CommunicationException">Thrown if the message could not be decoded.</exception>
public Message DecodeMessage(WcfEnvelopeMsg msg)
{
using (BlockStream bs = new BlockStream((Block)msg.Payload))
{
try
{
return(messageEncoderFactory.Encoder.ReadMessage(bs, ServiceModelHelper.MaxXmlHeaderSize));
}
catch (Exception e)
{
throw ServiceModelHelper.GetCommunicationException(e);
}
}
}
/// <summary>
/// Synchronously sends a message on the output channel.
/// </summary>
/// <param name="message">The <see cref="Message" />.</param>
/// <remarks>
/// <note>
/// This method does not guarantee delivery of the message.
/// Messages can be silently dropped for reasons including lack of buffer
/// space, network congestion, unavailable remote endpoint, etc.
/// </note>
/// </remarks>
public void Send(Message message)
{
try
{
using (MemoryStream ms = new MemoryStream(payloadEstimator.EstimateNextBufferSize()))
{
WcfEnvelopeMsg envelopeMsg = new WcfEnvelopeMsg();
encoder.WriteMessage(message, ms);
payloadEstimator.LastPayloadSize((int)ms.Length);
envelopeMsg.Payload = new ArraySegment <byte>(ms.GetBuffer(), 0, (int)ms.Length);
ChannelHost.Router.SendTo(ep, envelopeMsg);
}
}
catch (Exception e)
{
throw ServiceModelHelper.GetCommunicationException(e);
}
}
/// <summary>
/// Called when the message router receives a LillTek message.
/// </summary>
/// <param name="msg">The received message.</param>
private void OnReceive(Msg msg)
{
try
{
if (sessionMode)
{
DuplexSessionMsg duplexMsg = msg as DuplexSessionMsg;
// Handle client session connection attempts.
if (duplexMsg != null)
{
OnSessionConnect(duplexMsg);
return;
}
}
else
{
// Handle encapsulated WCF messages.
WcfEnvelopeMsg envelopeMsg = msg as WcfEnvelopeMsg;
Message message;
if (envelopeMsg == null)
{
return; // Discard non-envelope messages
}
message = DecodeMessage(envelopeMsg);
// Let the derived listener decide what to do with the message.
OnMessageReceived(message, envelopeMsg);
}
}
catch (Exception e)
{
SysLog.LogException(e);
}
}
/// <summary> /// Called when the base class receives a LillTek envelope message with an /// encapsulated WCF message from the router. Non-session oriented derived /// classes must implement this to accept a new channel or route the message /// to an existing channel. /// </summary> /// <param name="message">The decoded WCF <see cref="Message" />.</param> /// <param name="msg">The received LillTek <see cref="Msg" />.</param> protected abstract void OnMessageReceived(Message message, WcfEnvelopeMsg msg);
/// <summary>
/// Called when the base class receives a LillTek envelope message with an
/// encapsulated WCF message from the router. Non-session oriented derived
/// classes must implement this to accept a new channel or route the message
/// to an existing channel.
/// </summary>
/// <param name="message">The decoded WCF <see cref="Message" />.</param>
/// <param name="msg">The received LillTek <see cref="Msg" />.</param>
/// <remarks>
/// <para>
/// This method takes different actions depending on whether there are
/// any pending channel <b>WaitForMessage()</b> or <b>Receive()</b> requests.
/// </para>
/// <para>
/// If there are pending message receive operations, then these will be completed
/// and the message queued to the associated channel as is appropriate.
/// </para>
/// <para>
/// Finally, if no pending message receive requests and the base class has a
/// pending <b>WaitForChannel()</b> or <b>AcceptChannel()</b>, then the base class
/// <see cref="LillTekChannelListener{IInputSessionChannel,InputSessionChannel}.OnChannelCreated" />
/// method will be called so that a new channel will be accepted.
/// </para>
/// <para>
/// Finally, if there are no pending message receive requests or base channel
/// channel accept related requests, the message will be queued internally.
/// </para>
/// </remarks>
protected override void OnMessageReceived(Message message, WcfEnvelopeMsg msg)
{
InputChannel newChannel = null;
if (base.State != CommunicationState.Opened)
{
return;
}
if (msg._SessionID != Guid.Empty)
{
return; // Reject messages that are part of a session
}
using (TimedLock.Lock(this))
{
// Handle any pending channel Receive() operations first.
if (receiveQueue.Count > 0)
{
AsyncResult <Message, InputChannel> arReceive;
arReceive = receiveQueue.Dequeue();
arReceive.Result = message;
arReceive.Notify();
return;
}
// Next, handle any pending channel WaitForMessage() operations.
if (waitQueue.Count > 0)
{
AsyncResult <bool, InputChannel> arWait;
// Queue the message to the input channel so it will assured
// to be available when the WaitForMessage() completes and
// the application calls Receive().
arWait = waitQueue.Dequeue();
arWait.Result = true;
arWait.InternalState.Enqueue(message);
arWait.Notify();
return;
}
// Queue the message.
msgQueue.Enqueue(message);
// Create new channel if there are pending channel accept
// or wait operations.
if (base.HasPendingChannelOperation)
{
newChannel = new InputChannel(this, new EndpointAddress(this.Uri));
AddChannel(newChannel);
}
}
// Do this outside of the lock just to be safe
if (newChannel != null)
{
base.OnChannelCreated(newChannel);
}
}
/// <summary>
/// Called when the base class receives a LillTek envelope message with an
/// encapsulated WCF message from the router. Non-session oriented derived
/// classes must implement this to accept a new channel or route the message
/// to an existing channel.
/// </summary>
/// <param name="message">The decoded WCF <see cref="Message" />.</param>
/// <param name="msg">The received LillTek <see cref="Msg" />.</param>
/// <remarks>
/// <para>
/// This method takes different actions depending on whether there are
/// any pending channel <b>WaitForMessage()</b> or <b>Receive()</b> requests.
/// </para>
/// <para>
/// If there are pending message receive operations, then these will be completed
/// and the message queued to the associated channel as is appropriate.
/// </para>
/// <para>
/// Finally, if no pending message receive requests and the base class has a
/// pending <b>WaitForChannel()</b> or <b>AcceptChannel()</b>, then the base class
/// <see cref="LillTekChannelListener{IInputSessionChannel,InputSessionChannel}.OnChannelCreated" />
/// method will be called so that a new channel will be accepted.
/// </para>
/// <para>
/// Finally, if there are no pending message receive requests or base channel
/// channel accept related requests, the message will be queued internally.
/// </para>
/// </remarks>
protected override void OnMessageReceived(Message message, WcfEnvelopeMsg msg)
{
throw new InvalidOperationException();
}
/// <summary>
/// Called when the base class receives a LillTek envelope message with an
/// encapsulated WCF message from the router. Non-session oriented derived
/// classes must implement this to accept a new channel or route the message
/// to an existing channel.
/// </summary>
/// <param name="message">The decoded WCF <see cref="Message" />.</param>
/// <param name="msg">The received LillTek <see cref="Msg" />.</param>
protected override void OnMessageReceived(Message message, WcfEnvelopeMsg msg)
{
}
/// <summary>
/// Called when the base class receives a LillTek envelope message with an
/// encapsulated WCF message from the router. Non-session oriented derived
/// classes must implement this to accept a new channel or route the message
/// to an existing channel.
/// </summary>
/// <param name="message">The decoded WCF <see cref="Message" />.</param>
/// <param name="msg">The received LillTek <see cref="Msg" />.</param>
/// <remarks>
/// <para>
/// This method takes different actions depending on whether there are
/// any pending channel <b>WaitForRequest()</b> or <b>ReceiveRequest()</b> requests.
/// </para>
/// <para>
/// If there are pending request receive operations, then these will be completed
/// and the rfequest information will be queued to the associated channel as is appropriate.
/// </para>
/// <para>
/// Finally, if no pending request receive requests and the base class has a
/// pending <b>WaitForChannel()</b> or <b>AcceptChannel()</b>, then the base class
/// <see cref="LillTekChannelListener{IInputSessionChannel,InputSessionChannel}.OnChannelCreated" />
/// method will be called so that a new channel will be accepted.
/// </para>
/// <para>
/// Finally, if there are no pending request receive requests or base channel
/// channel accept related requests, the message will be queued internally.
/// </para>
/// </remarks>
protected override void OnMessageReceived(Message message, WcfEnvelopeMsg msg)
{
RequestInfo requestInfo = new RequestInfo(message, msg.CreateRequestContext(), SysTime.Now + maxRequestQueueTime);
ReplyChannel newChannel = null;
if (base.State != CommunicationState.Opened)
{
return;
}
using (TimedLock.Lock(this))
{
// Handle any pending channel ReceiveRequest() operations first.
if (receiveQueue.Count > 0)
{
AsyncResult <RequestInfo, ReplyChannel> arReceive;
arReceive = receiveQueue.Dequeue();
arReceive.Result = requestInfo;
arReceive.Notify();
return;
}
// Next, handle any pending channel WaitForRequest() operations.
if (waitQueue.Count > 0)
{
AsyncResult <bool, ReplyChannel> arWait;
// Queue the request information to the input channel so it will assured
// to be available when the WaitForRequest() completes and
// the application calls ReceiveRequest().
arWait = waitQueue.Dequeue();
arWait.Result = true;
arWait.InternalState.Enqueue(requestInfo);
arWait.Notify();
return;
}
// Queue the request.
requestQueue.Enqueue(requestInfo);
// Create new channel if there are pending channel accept
// or wait operations.
if (base.HasPendingChannelOperation)
{
newChannel = new ReplyChannel(this, new EndpointAddress(this.Uri), base.MessageEncoder);
AddChannel(newChannel);
}
}
// Do this outside of the lock just to be safe
if (newChannel != null)
{
base.OnChannelCreated(newChannel);
}
}
