SSE Exceptions while publishing notifications

ServiceStack Server Events
1

Hi Demis,
we are using server sent events with redis. we have almost no load on the server and see from time to time the following exception:

Error  [ServiceStack.EventSubscription] Error publishing notification to: id: 10
data: claims/33@cmd.onJoin {"userId":"claim System.Web.HttpException The remote host closed the connection. The error code is 0x800704CD.    at System.Web.Hosting.IIS7WorkerRequest.RaiseCommunicationError(Int32 result, Boolean throwOnDisconnect)
   at System.Web.Hosting.IIS7WorkerRequest.ExplicitFlush()
   at System.Web.HttpResponse.Flush(Boolean finalFlush, Boolean async)
   at System.Web.HttpWriter.WriteFromStream(Byte[] data, Int32 offset, Int32 size)
   at ServiceStack.ServerEventsFeature.<>c.<.ctor>b__76_0(IResponse res, String frame)
   at ServiceStack.EventSubscription.PublishRaw(String frame)

we added your recommended compression settings:

<urlCompression doStaticCompression="true" doDynamicCompression="false" />

Can you explain why this exception occurs? Is it because it tried to send something to a client which isn’t connected anymore?

another thing maybe worth to mention: it runs on Azure, IIS VM with redis as a service from azure.

cheers
tobi

2

Right, the long-running http connection to the client was lost and SSE throws this error when it tries to write to the clients HTTP connection.

3

ok happy to hear that. but i think the log level feels wrong to me (error…)

4

No worries, we’re not married to the log-level :slight_smile: modified to Warn in this commit.

5

yeah luckily we aren’t :smiley:

but if i put errors/warns into prod, I won’t get friends in the ops department :smile:

Exception -> Debug
Info -> some nice verbal message that the client is gone and no message delivered.

i moved it to debug with NLog config :angel:

but anyway thanks for the clarification!