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Spring an Quartz JobDataMap serialization exception

We dont run our nodes in HA yet and once a customer registers he is assigned a node and he lives there. Problem is that if the node dies we incur a downtime for that customer and also we need to overallocate hardware to prepare for worse case scenario.  for the past 6 months I have been working to making the code stateless so that we can do HA and reduce our node count by 4 times.

So we used to run quartz using in memory scheduler but for HA I need to run quartz in a cluster. We chose org.quartz.impl.jdbcjobstore.JobStoreTX for this.

Problem was that as soon as I tried it I ran into issues because I was injecting spring beans into our quartz job using JobDataMap and JobStoreTX was trying to serialize the jobData into a table and our spring beans are not serializable.  There were two options:

1) Load the entire applicationContext in each job and read the bean from there.

2) Use the schedulerContextAsMap.

After evaluating options I found scheduler context as the best option .The way to do this would be

    <bean id="haQuartzScheduler" class="org.springframework.scheduling.quartz.SchedulerFactoryBean">
        <property name="configLocation" value="classpath:quartz.properties"/>
        <property name="triggers">
            <list>
                <ref bean="CommitFileJobTrigger" />
            </list>
        </property>
        <property name="schedulerContextAsMap">
            <map>
                <entry key="commitFileJobHelper" value-ref="commitFileJobHelper" />
                <entry key="numThreads" value="2" />           
            </map>
        </property>
    </bean>

In the quartz job I wrote a function

    protected T getSchedulerContextBean(JobExecutionContext context, String beanName) throws JobExecutionException {
        SchedulerContext schedulerContext;
        try {
            schedulerContext = context.getScheduler().getContext();
        } catch (SchedulerException e) {
            throw new JobExecutionException(e);
        }
        T bean = (T)schedulerContext.get(beanName);
        return bean;
    }    


and then all jobs can use this function like

        CommitFileJobHelper commitFileJobHelper = getSchedulerContextBean(context, "commitFileJobHelper");

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