Trying to parse unhandled events in the plugin will throw an exception, while it should just skip them.

See for example:

INFO: Received body: {"project":"test-repo","ref":"refs/meta/config","targetNode":"gerrit-2:9418","type":"ref-replication-scheduled","eventCreatedOn":1552040918}INFO: Received body: {"project":"test-repo","ref":"refs/meta/config","targetNode":"gerrit-2:9418","type":"ref-replication-scheduled","eventCreatedOn":1552040918}Mar 08, 2019 10:28:56 AM org.eclipse.jetty.server.handler.ContextHandler$Context logWARNING: Error while serving http://9588e6bcfeae:8080/gerrit-webhook/java.lang.reflect.InvocationTargetException at org.kohsuke.stapler.Function$MethodFunction.invoke(Function.java:400) at org.kohsuke.stapler.Function$InstanceFunction.invoke(Function.java:408) at org.kohsuke.stapler.Function.bindAndInvoke(Function.java:212) at org.kohsuke.stapler.Function.bindAndInvokeAndServeResponse(Function.java:145) at org.kohsuke.stapler.IndexDispatcher.dispatch(IndexDispatcher.java:27) at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:739) at org.kohsuke.stapler.Stapler.invoke(Stapler.java:870) at org.kohsuke.stapler.MetaClass$9.dispatch(MetaClass.java:458) at org.kohsuke.stapler.Stapler.tryInvoke(Stapler.java:739) at org.kohsuke.stapler.Stapler.invoke(Stapler.java:870) at org.kohsuke.stapler.Stapler.invoke(Stapler.java:668) at org.kohsuke.stapler.Stapler.service(Stapler.java:238) at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:865) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1655) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:154) at org.jenkinsci.plugins.ssegateway.Endpoint$SSEListenChannelFilter.doFilter(Endpoint.java:243) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:151) at io.jenkins.blueocean.ResourceCacheControl.doFilter(ResourceCacheControl.java:134) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:151) at io.jenkins.blueocean.auth.jwt.impl.JwtAuthenticationFilter.doFilter(JwtAuthenticationFilter.java:61) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:151) at jenkins.telemetry.impl.UserLanguages$AcceptLanguageFilter.doFilter(UserLanguages.java:128) at hudson.util.PluginServletFilter$1.doFilter(PluginServletFilter.java:151) at hudson.util.PluginServletFilter.doFilter(PluginServletFilter.java:157) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) at jenkins.plugins.gerrit.GerritWebHookCrumbExclusion.process(GerritWebHookCrumbExclusion.java:25) at hudson.security.csrf.CrumbFilter.doFilter(CrumbFilter.java:73) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) 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:135) 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$1.doFilter(ChainedServletFilter.java:87) at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:90) at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:171) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:49) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) at hudson.util.CharacterEncodingFilter.doFilter(CharacterEncodingFilter.java:82) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) at org.kohsuke.stapler.DiagnosticThreadNameFilter.doFilter(DiagnosticThreadNameFilter.java:30) at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1642) at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:533) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:146) at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:524) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:257) at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:1595) at org.eclipse.jetty.server.handler.ScopedHandler.nextHandle(ScopedHandler.java:255) at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1340) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:203) at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:473) at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:1564) at org.eclipse.jetty.server.handler.ScopedHandler.nextScope(ScopedHandler.java:201) at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1242) at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:144) at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:132) at org.eclipse.jetty.server.Server.handle(Server.java:503) at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:364) at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:260) at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305) at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103) at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.runTask(EatWhatYouKill.java:333) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.doProduce(EatWhatYouKill.java:310) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.tryProduce(EatWhatYouKill.java:168) at org.eclipse.jetty.util.thread.strategy.EatWhatYouKill.run(EatWhatYouKill.java:126) at org.eclipse.jetty.util.thread.ReservedThreadExecutor$ReservedThread.run(ReservedThreadExecutor.java:366) at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:765) at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:683) at java.lang.Thread.run(Thread.java:748)Caused by: com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING at line 1 column 13 path $.project at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:224) at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:129) at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:220) at com.google.gson.Gson.fromJson(Gson.java:888) at com.google.gson.Gson.fromJson(Gson.java:853) at com.google.gson.Gson.fromJson(Gson.java:802) at com.google.gson.Gson.fromJson(Gson.java:774) at jenkins.plugins.gerrit.GerritWebHook.getBody(GerritWebHook.java:94) at jenkins.plugins.gerrit.GerritWebHook.doIndex(GerritWebHook.java:66) at java.lang.invoke.MethodHandle.invokeWithArguments(MethodHandle.java:627) at org.kohsuke.stapler.Function$MethodFunction.invoke(Function.java:396) ... 82 moreCaused by: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was STRING at line 1 column 13 path $.project at com.google.gson.stream.JsonReader.beginObject(JsonReader.java:385) at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:213) ... 92 more