void TrackSession(HttpSession session)
{
sessionTable[session.Id] = session;
var sessionCount = sessionTable.Count;
int currentMax;
while ((currentMax = maxConnectedSessions) < sessionCount)
{
if (Interlocked.CompareExchange(ref maxConnectedSessions, sessionCount, currentMax) != currentMax)
{
continue;
}
}
}
bool HandleWebsocketUpgrade(HttpSession session,
int routeTableIndex,
int endpointIndex,
WebSocketUpgradeResponse response,
out int responseBytesWritten)
{
responseBytesWritten = session.WriteWebSocketUpgradeResponse(response);
var acceptUpgradeResponse = response as WebSocketUpgradeResponse.AcceptUpgradeResponse;
if (acceptUpgradeResponse == null)
{
return false;
}
else
{
long id = Interlocked.Increment(ref acceptedWebSocketSessions);
var webSocketSession = new WebSocketSession(id,
session.TcpClient,
session.Stream,
bytesReceived => router.Metrics.CountRequestBytesIn(routeTableIndex, endpointIndex, bytesReceived),
bytesSent => router.Metrics.CountResponseBytesOut(routeTableIndex, endpointIndex, bytesSent),
() => UntrackWebSocketSession(id));
TrackWebSocketSession(webSocketSession);
try
{
acceptUpgradeResponse.OnAccepted(webSocketSession); //TODO: Task.Run this?
return true;
}
catch (Exception e)
{
UntrackWebSocketSession(id);
logger.Error("Error calling WebSocketUpgradeResponse.OnAccepted callback - {0}", e.ToString());
return false;
}
}
}
async Task<int> AcceptWebSocketUpgrade(HttpSession session,
int routeTableIndex,
int endpointIndex,
WebSocketUpgradeResponse.AcceptUpgradeResponse response)
{
var bytesWritten = await response.WriteToAsync(session.Stream, 0, sessionReadTimeout).ConfigureAwait(false);
var id = Interlocked.Increment(ref acceptedWebSocketSessions);
var webSocketSession = new WebSocketSession(id,
session.TcpClient,
session.Stream,
bytesReceived => router.Metrics.CountRequestBytesIn(routeTableIndex, endpointIndex, bytesReceived),
bytesSent => router.Metrics.CountResponseBytesOut(routeTableIndex, endpointIndex, bytesSent),
() => UntrackWebSocketSession(id),
sessionReadBufferSize,
(int)sessionReadTimeout.TotalMilliseconds,
(int)sessionWriteTimeout.TotalMilliseconds);
TrackWebSocketSession(webSocketSession);
try
{
response.OnAccepted(webSocketSession); //TODO: Task.Run this?
return bytesWritten;
}
catch (Exception)
{
UntrackWebSocketSession(id);
throw;
}
}
async Task HandleSession(HttpSession session)
{
var closeSessionOnReturn = true;
try
{
var continueSession = true;
while (continueSession && !session.IsDisconnected())
{
try
{
TrackSessionRead(session.Id);
if (await session.ReadToBufferAsync().ConfigureAwait(false) == 0) // 0 => client clean disconnect
{
break;
}
}
finally
{
UntrackSessionRead(session.Id);
}
int requestBytesParsed, responseBytesWritten;
HttpRequest request;
while (continueSession && session.TryParseNextRequestFromBuffer(out requestBytesParsed, out request))
{
Router.HandleResult result = await router.HandleRequest(request, DateTime.UtcNow).ConfigureAwait(false);
HttpResponse response = result.HttpResponse;
var webSocketUpgradeResponse = response as WebSocketUpgradeResponse;
if (webSocketUpgradeResponse == null)
{
responseBytesWritten = session.WriteResponse(response, request.IsKeepAlive);
continueSession = request.IsKeepAlive && session.KeepAlivesRemaining > 0;
}
else
{
var isUpgraded = HandleWebsocketUpgrade(session,
result.MatchedRouteTableIndex,
result.MatchedEndpointIndex,
webSocketUpgradeResponse,
out responseBytesWritten);
continueSession = false;
closeSessionOnReturn = !isUpgraded;
}
if (result.MatchedRouteTableIndex >= 0 && result.MatchedEndpointIndex >= 0)
{
router.Metrics.CountBytes(result.MatchedRouteTableIndex, result.MatchedEndpointIndex, requestBytesParsed, responseBytesWritten);
}
}
}
}
catch (RequestException e)
{
logger.Warn("Error parsing or bad request - {0}", e.Message);
}
catch (SessionStreamException)
{
// forced disconnect, socket errors
}
catch (Exception e)
{
//TODO: count session-fatal errors (not captured as route table 500s)
logger.Fatal("Internal server error handling session - {0}", e.ToString());
}
finally
{
UntrackSession(session.Id);
if (closeSessionOnReturn)
{
session.CloseQuiety();
}
}
}
async Task HandleSession(HttpSession session)
{
var closeSessionOnReturn = true;
try
{
var continueRequestLoop = true;
while (continueRequestLoop && !session.IsDisconnected()) // request loop
{
try
{
TrackSessionRead(session.Id);
if (await session.ReadToBufferAsync().ConfigureAwait(false) == 0) // 0 => client clean disconnect
{
break;
}
}
finally
{
UntrackSessionRead(session.Id);
}
int requestBytesParsed, responseBytesWritten;
HttpRequest request;
while (continueRequestLoop && session.TryParseNextRequestFromBuffer(out requestBytesParsed, out request))
{
Router.HandleResult result = await router.HandleRequest(request, DateTime.UtcNow).ConfigureAwait(false);
HttpResponse response = result.HttpResponse;
if (response is WebSocketUpgradeResponse)
{
continueRequestLoop = false;
var acceptUpgrade = response as WebSocketUpgradeResponse.AcceptUpgradeResponse;
if (acceptUpgrade == null)
{
var rejectUpgrade = (WebSocketUpgradeResponse.RejectUpgradeResponse)response;
responseBytesWritten = await rejectUpgrade.WriteToAsync(session.Stream, 0, sessionReadTimeout).ConfigureAwait(false);
}
else
{
responseBytesWritten = await AcceptWebSocketUpgrade(session, result.MatchedRouteTableIndex, result.MatchedEndpointIndex, acceptUpgrade).ConfigureAwait(false);
closeSessionOnReturn = false;
}
}
else
{
responseBytesWritten = await response.WriteToAsync(session.Stream, request.IsKeepAlive ? session.KeepAlivesRemaining : 0, sessionReadTimeout).ConfigureAwait(false);
continueRequestLoop = request.IsKeepAlive && session.KeepAlivesRemaining > 0;
}
if (result.MatchedRouteTableIndex >= 0 && result.MatchedEndpointIndex >= 0)
{
router.Metrics.CountBytes(result.MatchedRouteTableIndex, result.MatchedEndpointIndex, requestBytesParsed, responseBytesWritten);
}
}
}
}
catch (RequestException e)
{
sessionExceptionCounters.Count(e.GetType());
logger.Warn("Error parsing or bad request - {0}", e.Message);
}
catch (SessionStreamException e)
{
sessionExceptionCounters.Count(e.GetType());
}
catch (Exception e)
{
sessionExceptionCounters.Count(e.GetType());
logger.Fatal("Error handling session - {0}", e.ToString());
}
finally
{
UntrackSession(session.Id);
if (closeSessionOnReturn)
{
session.CloseQuiety();
}
}
}
