Slack Build Notifier Recently Started Failing

[TKammerer]

Here is the stack trace from the TC server. It was working well for sometime then out of the blue started to stop working. I'm stronger with C# than java. I have attempted to read through the source but cannot make too much since of it in the short term. Hoping someone here has experienced this same issue.

Dec 30, 2016 1:12:22 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [buildServer] in context with path [] threw exception
java.io.IOException: Attempted read from closed stream.
at org.apache.http.impl.io.ContentLengthInputStream.read(ContentLengthInputStream.java:167)
at org.apache.http.conn.EofSensorInputStream.read(EofSensorInputStream.java:137)
at sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284)
at sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326)
at sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178)
at java.io.InputStreamReader.read(InputStreamReader.java:184)
at java.io.Reader.read(Reader.java:140)
at org.apache.http.util.EntityUtils.toString(EntityUtils.java:244)
at org.apache.http.util.EntityUtils.toString(EntityUtils.java:288)
at slacknotifications.SlackNotificationImpl.postViaWebHook(SlackNotificationImpl.java:261)
at slacknotifications.SlackNotificationImpl.post(SlackNotificationImpl.java:157)
at slacknotifications.teamcity.extension.SlackNotifierSettingsController.handleTestNotification(SlackNotifierSettingsController.java:136)
at slacknotifications.teamcity.extension.SlackNotifierSettingsController.doHandle(SlackNotifierSettingsController.java:88)
at jetbrains.buildServer.controllers.BaseController.handleRequestInternal(BaseController.java:75)
at org.springframework.web.servlet.mvc.AbstractController.handleRequest(AbstractController.java:147)
at org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter.handle(SimpleControllerHandlerAdapter.java:50)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:961)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:895)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:967)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:858)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
at jetbrains.buildServer.maintenance.TeamCityDispatcherServlet.service(TeamCityDispatcherServlet.java:21)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at jetbrains.buildServer.web.DisableSessionIdFromUrlFilter.doFilter(DisableSessionIdFromUrlFilter.java:7)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:107)
at jetbrains.buildServer.diagnostic.web.DiagnosticFilter.doFilter(DiagnosticFilter.java:23)
at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:112)
at jetbrains.buildServer.web.DependencyParametersCalculationContextFilter.doFilter(DependencyParametersCalculationContextFilter.java:1)
at org.springframework.web.filter.CompositeFilter$VirtualFilterChain.doFilter(CompositeFilter.java:112)
at org.springframework.web.filter.CompositeFilter.doFilter(CompositeFilter.java:73)
at jetbrains.buildServer.web.DelegatingFilter.doFilter(DelegatingFilter.java:11)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at jetbrains.buildServer.web.ResponseFragmentFilter.doFilter(ResponseFragmentFilter.java:10)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:614)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)

[TKammerer]

I found the issue. Someone had changed the "default channel" in the admin area for the Slack Notification to one that didn't exist. I pulled the body and URL from the logs on the TC server and used postman to get the "channel_not_found" response from slack. This should probably be made into an enhancement that surfaces the actual issue instead of the "Attempted read from closed stream" because I'm assuming it cannot properly understand the response from slack if it isn't "ok". Also when these slack configurations are attributed to builds in TeamCity and the slack notification fails, it is a silent failure and you don't know there is a problem. I would also suggest looking into surfacing the failure sooner.

[PeteGoo]

Sorry you experienced this error. Sounds like a good plan for the fix. Thanks

[StephenDrewLDS]

I'm also getting this error, but the channel exists (private channel) and the test notifications work. Any ideas?