Jenkins / Slack integration

Question

I need to configure Jenkins to send notification on our Slack channel #builds. I configured the Jenkins CI integration in Slack. As a result, I have a token "abcdefgh666", and when I expand the "Setup instructions", I can see our team domain is "mysuperteam". We connect to slack with the url http://mysuperteam.slack.com

I am stuck on step 3. On Slack doc, the screenshot is the following:

But in our Jenkins version, the view looks like:

Obviously, the Test Connection button always return a Failure. In Jenkins logs, I have this many times:

Mar 30, 2017 2:14:38 PM WARNING jenkins.plugins.slack.StandardSlackService publish
Error posting to Slack
java.lang.IllegalStateException: Target host is null
    at org.apache.http.util.Asserts.notNull(Asserts.java:46)
    at org.apache.http.impl.client.InternalHttpClient.determineRoute(InternalHttpClient.java:125)
    at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:185)
    at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)
    at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:106)
    at jenkins.plugins.slack.StandardSlackService.publish(StandardSlackService.java:126)
    at jenkins.plugins.slack.SlackNotifier$DescriptorImpl.doTestConnection(SlackNotifier.java:510)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:335)
    at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:175)
    at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:108)
    at org.kohsuke.stapler.MetaClass$1.doDispatch(MetaClass.java:124)
    at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)
    at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)
    at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)
    at org.kohsuke.stapler.MetaClass$5.doDispatch(MetaClass.java:236)
    at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)
    at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)
    at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)
    at org.kohsuke.stapler.MetaClass$5.doDispatch(MetaClass.java:236)
    at org.kohsuke.stapler.NameBasedDispatcher.dispatch(NameBasedDispatcher.java:58)
    at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:746)
    at org.kohsuke.stapler.Stapler.invoke(Stapler.java:876)
    at org.kohsuke.stapler.Stapler.invoke(Stapler.java:649)
    at org.kohsuke.stapler.Stapler.service(Stapler.java:238)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
    at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:812)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1669)
    at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:135)
    at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:126)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
    at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:80)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:84)
    at hudson.security.UnwrapSecurityExceptionFilter.doFilter(UnwrapSecurityExceptionFilter.java:51)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
    at jenkins.security.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:117)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
    at org.acegisecurity.providers.anonymous.AnonymousProcessingFilter.doFilter(AnonymousProcessingFilter.java:125)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
    at org.acegisecurity.ui.rememberme.RememberMeProcessingFilter.doFilter(RememberMeProcessingFilter.java:142)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
    at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:271)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
    at jenkins.security.BasicHeaderProcessor.doFilter(BasicHeaderProcessor.java:93)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
    at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
    at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:67)
    at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
    at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
    at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
    at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
    at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:82)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
    at org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30)
    at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1652)
    at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:585)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
    at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:553)
    at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:223)
    at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1127)
    at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:515)
    at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
    at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1061)
    at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
    at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:97)
    at org.eclipse.jetty.server.Server.handle(Server.java:499)
    at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:311)
    at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:257)
    at org.eclipse.jetty.io.AbstractConnection$2.run(AbstractConnection.java:544)
    at winstone.BoundedExecutorService$1.run(BoundedExecutorService.java:77)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:745)

I tried using the credentials menu to avoid putting the token directly, I tried to put "slack.com" in "Base URL" field, I tried to check or uncheck the "Is Bot User ?" field, and I tried to put "http://mysuperteam.slack.com" in "Base URL" field.

Is my configuration correct ? What could prevent Jenkins to connect to Slack ?

Answer 1

Finally, the issue was a temporary bug. Our configuration was valid, and re-testing a few days later seems to work well.

We filled Team Subdomain and Integration Token inputs with information found in our Slack apps management page. In addition, we set the name of the Channel were Jenkins will push notifications:

We didn't set nothing in Slack Webhooks Settings:

Important: Remember to save your settings before clicking on "Test Connection" button.

Versions: Jenkins 2.46 / Slack Notification Plugin 2.2. Settings info found on https://github.com/jenkinsci/slack-plugin