NPE found when rabbitmq event bus is configured with cloudstack

[kiranchavala]

problem

NPE found when rabbitmq event bus is configured

versions

ACS 4.22

The steps to reproduce the bug

1. Configure Rabbitma event bus

https://docs.cloudstack.apache.org/en/4.22.0.0/adminguide/events.html#amqp-configuration

2. Stop the rabbit mq server

3. Stop the cloudstack-management server

4. Check the logs

2026-02-12 06:05:07,916 ERROR [o.a.c.s.l.CloudStackExtendedLifeCycle] (SpringContextShutdownHook:[]) (logid:) Error on stopping bean RabbitMQEventBus - Cannot invoke "com.rabbitmq.client.Connection.isOpen()" because "org.apache.cloudstack.mom.rabbitmq.RabbitMQEventBus.s_connection" is null java.lang.NullPointerException: Cannot invoke "com.rabbitmq.client.Connection.isOpen()" because "org.apache.cloudstack.mom.rabbitmq.RabbitMQEventBus.s_connection" is null
        at org.apache.cloudstack.mom.rabbitmq.RabbitMQEventBus.stop(RabbitMQEventBus.java:496)
        at org.apache.cloudstack.spring.lifecycle.CloudStackExtendedLifeCycle$2.with(CloudStackExtendedLifeCycle.java:103)
        at org.apache.cloudstack.spring.lifecycle.CloudStackExtendedLifeCycle.with(CloudStackExtendedLifeCycle.java:163)
        at org.apache.cloudstack.spring.lifecycle.CloudStackExtendedLifeCycle.stopBeans(CloudStackExtendedLifeCycle.java:98)
        at org.apache.cloudstack.spring.lifecycle.CloudStackExtendedLifeCycleStart.stop(CloudStackExtendedLifeCycleStart.java:27)
        at org.apache.cloudstack.spring.lifecycle.AbstractSmartLifeCycle.stop(AbstractSmartLifeCycle.java:52)
        at org.springframework.context.support.DefaultLifecycleProcessor.doStop(DefaultLifecycleProcessor.java:234)
        at org.springframework.context.support.DefaultLifecycleProcessor.access$300(DefaultLifecycleProcessor.java:54)
        at org.springframework.context.support.DefaultLifecycleProcessor$LifecycleGroup.stop(DefaultLifecycleProcessor.java:373)
        at org.springframework.context.support.DefaultLifecycleProcessor.stopBeans(DefaultLifecycleProcessor.java:206)
        at org.springframework.context.support.DefaultLifecycleProcessor.onClose(DefaultLifecycleProcessor.java:129)
        at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:1069)
        at org.springframework.context.support.AbstractApplicationContext$1.run(AbstractApplicationContext.java:993)

What to do about it?

Cloudstack should check rabbitmq connectivity when stopping the service