Plugin doesn't work with Graylog 4.1

[geekifier]

When trying to create a new notification, I get the following error:

java.lang.NoSuchMethodError:
        org.graylog2.plugin.rest.ValidationResult.addError(Ljava/lang/String;Ljava/lang/String;)V

org.glassfish.jersey.server.ContainerException: java.lang.NoSuchMethodError: org.graylog2.plugin.rest.ValidationResult.addError(Ljava/lang/String;Ljava/lang/String;)V at org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpContainer$ResponseWriter.rethrow(GrizzlyHttpContainer.java:297) at org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpContainer$ResponseWriter.failure(GrizzlyHttpContainer.java:279) at org.glassfish.jersey.server.ServerRuntime$Responder.process(ServerRuntime.java:438) at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:263) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:248) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:244) at org.glassfish.jersey.internal.Errors.process(Errors.java:292) at org.glassfish.jersey.internal.Errors.process(Errors.java:274) at org.glassfish.jersey.internal.Errors.process(Errors.java:244) at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:265) at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:234) at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:680) at org.glassfish.jersey.grizzly2.httpserver.GrizzlyHttpContainer.service(GrizzlyHttpContainer.java:356) at org.glassfish.grizzly.http.server.HttpHandler$1.run(HttpHandler.java:200) at com.codahale.metrics.InstrumentedExecutorService$InstrumentedRunnable.run(InstrumentedExecutorService.java:180) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:750) Caused by: java.lang.NoSuchMethodError: org.graylog2.plugin.rest.ValidationResult.addError(Ljava/lang/String;Ljava/lang/String;)V at com.itchannel.PushNotificationConfig.validate(PushNotificationConfig.java:70) at org.graylog.events.notifications.NotificationDto.validate(NotificationDto.java:75) at org.graylog.events.rest.EventNotificationsResource.create(EventNotificationsResource.java:123) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.glassfish.jersey.server.model.internal.ResourceMethodInvocationHandlerFactory.lambda$static$0(ResourceMethodInvocationHandlerFactory.java:52) at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher$1.run(AbstractJavaResourceMethodDispatcher.java:124) at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.invoke(AbstractJavaResourceMethodDispatcher.java:167) at org.glassfish.jersey.server.model.internal.JavaResourceMethodDispatcherProvider$ResponseOutInvoker.doDispatch(JavaResourceMethodDispatcherProvider.java:176) at org.glassfish.jersey.server.model.internal.AbstractJavaResourceMethodDispatcher.dispatch(AbstractJavaResourceMethodDispatcher.java:79) at org.glassfish.jersey.server.model.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:469) at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:391) at org.glassfish.jersey.server.model.ResourceMethodInvoker.apply(ResourceMethodInvoker.java:80) at org.glassfish.jersey.server.ServerRuntime$1.run(ServerRuntime.java:255) ... 14 more

[itchannel]

Fixed in 2.1