private AlarmEntity getAlarmEntity(int id) {
        MetaInAlarm metaInAlarm = getMetaInAlarm(id);
        return new AlarmEntity(metaInAlarm.getScope(), metaInAlarm.getScopeId(), metaInAlarm.getName(),
                               metaInAlarm.getId0(), metaInAlarm.getId1()
        );
    }
Running rule is the core of how does alarm work.
<p>
So in this test, we need to simulate a lot of scenario to see the reactions.
oap-server/server-alarm-plugin/src/test/java/org/apache/skywalking/oap/server/core/alarm/provider/RunningRuleTest.java