Managing Quartz Using Spring Boot Actuator

In this post, we will explore writing custom endpoints for managing Quartz entities like jobs and triggers using the Spring Boot Actuator framework.

What Is Missing?

The Spring Boot Actuator module provides various production-ready endpoints for managing and monitoring application. But strangely enough, it does not have out-of-the-box support for managing Quartz. Quarz is a very popular scheduler and is, for many, the de-facto standard for microservices that require scheduling abilities.

Why Is It Important?

In my experience, I have seen that when products get deployed in production, there might a situation where you want to pause/resume jobs/triggers. It could be because some job is bringing down the whole application or causing high resource usage, which in turn degrades overall performance. We could have tackled this situation by deploy new code but this might take more time or the organization might have a freeze period where no new deployments can happen.

This brings us to a point of requiring a way to manage Quartz jobs/triggers at run-time. This can be done by having application-specific code or leveraging the Spring Boot Actuator framework. Using the Spring Boot Actuator framework makes it easy to integrate with an application using Spring and can have a reusable module to be used across different applications

Quartz Job Endpoint

We will look at how to write a custom endpoint for supporting various operation on Quartz jobs. The below endpoints will be useful:

GET actuator/quartz-jobs?group=&name=
GET actuator/quartz-jobs/{jobgroup}/{jobname}
POST actuator/quartz-jobs/{jobgroup}/{jobname}/resume
POST actuator/quartz-jobs/{jobgroup}/{jobname}/pause

Let's look at the Java code to achieve this goal:

import java.util.Set;
import java.util.stream.Collectors;

import org.quartz.JobDetail;
import org.quartz.JobKey;
import org.quartz.Scheduler;
import org.quartz.SchedulerException;
import org.quartz.impl.matchers.GroupMatcher;
import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
import org.springframework.boot.actuate.endpoint.annotation.Selector;
import org.springframework.boot.actuate.endpoint.annotation.WriteOperation;
import org.springframework.lang.Nullable;

import org.sathyabodh.actuator.quartz.exception.UnsupportStateChangeException;
import org.sathyabodh.actuator.quartz.model.GroupModel;
import org.sathyabodh.actuator.quartz.model.JobDetailModel;
import org.sathyabodh.actuator.quartz.model.JobModel;
import org.sathyabodh.actuator.quartz.service.TriggerModelBuilder;

@Endpoint(id = "quartz-jobs")
public class QuartzJobEndPoint {

private Scheduler scheduler;

private TriggerModelBuilder triggerModelBuilder = new TriggerModelBuilder();

public QuartzJobEndPoint(Scheduler scheduler) {
this.scheduler = scheduler;
}

@ReadOperation
public GroupModel<JobModel> listJobs(@Nullable String group, @Nullable String name) throws SchedulerException {
try {
if (name != null && group != null) {
JobModel model = createJobModel(new JobKey(name, group));
if (model == null) {
return null;
}
GroupModel<JobModel> jobGroupModel = new GroupModel<>();
jobGroupModel.add(group, model);
return jobGroupModel;
}
GroupMatcher<JobKey> jobGroupMatcher = group == null ? GroupMatcher.anyJobGroup()
: GroupMatcher.jobGroupEquals(group);

Set<JobKey> jobKeys = scheduler.getJobKeys(jobGroupMatcher);
if (name != null) {
jobKeys = jobKeys.stream().filter(key -> name.equals(key.getName())).collect(Collectors.toSet());
}
if (jobKeys == null || jobKeys.isEmpty()) {
return null;
}
GroupModel<JobModel> jobGroupModel = new GroupModel<>();
jobKeys.forEach(key -> {
JobModel model = createJobModel(key);
jobGroupModel.add(key.getGroup(), model);
});
return jobGroupModel;
} catch (SchedulerException e) {
throw e;
}
}

@ReadOperation
public JobDetailModel getJobDetail(@Selector String group, @Selector String name) throws SchedulerException {
JobDetail jobDetail = scheduler.getJobDetail(new JobKey(name, group));
JobDetailModel model = new JobDetailModel();
copyJobDetailModel(jobDetail, model);
model.setGroup(jobDetail.getKey().getGroup());
model.setTriggers(triggerModelBuilder.buildTriggerDetailModel(scheduler, jobDetail.getKey()));
return model;
}

private JobModel createJobModel(JobKey key) {
try {
JobDetail jobDetail = scheduler.getJobDetail(key);
if (jobDetail == null) {
return null;
}
JobModel model = new JobModel();
copyJobDetailModel(jobDetail, model);
return model;

} catch (SchedulerException e) {
throw new RuntimeException(e);
}

}

private void copyJobDetailModel(JobDetail jobDetail, JobModel model) {
model.setName(jobDetail.getKey().getName());
model.setDurable(jobDetail.isDurable());
model.setConcurrentDisallowed(jobDetail.isConcurrentExectionDisallowed());
model.setJobClass(jobDetail.getJobClass().getName());
}

@WriteOperation
public boolean modifyJobStatus(@Selector String group, @Selector String name, @Selector String state)
throws SchedulerException {
JobKey jobKey = new JobKey(name, group);
JobDetail detail = scheduler.getJobDetail(jobKey);
if (detail == null)
return false;
else if (QuartzState.PAUSE.equals(state)) {
scheduler.pauseJob(jobKey);
} else if (QuartzState.RESUME.equals(state)) {
scheduler.resumeJob(jobKey);
} else {
throw new UnsupportStateChangeException(String.format("unsupported state change. state:[%s]", state));
}
return true;
}
}
-

Starting from Spring Boot 2.0, writing custom endpoints have changed a lot. They have made the Actuator endpoint technology-independent, i.e. JMX, WebMVC, SpringFlux. Hence, the annotation names are very generic. Please refer to the Spring Actuator documentation for annotation details

To add some specific code when used as an HTTP endpoint, we can write an Extension. This gives us the required hook for our chosen technology. The code below shows a web-specific extension.

import org.quartz.SchedulerException;
import org.springframework.boot.actuate.endpoint.annotation.Selector;
import org.springframework.boot.actuate.endpoint.annotation.WriteOperation;
import org.springframework.boot.actuate.endpoint.web.WebEndpointResponse;
import org.springframework.boot.actuate.endpoint.web.annotation.EndpointWebExtension;

import org.sathyabodh.actuator.quartz.exception.UnsupportStateChangeException;

@EndpointWebExtension(endpoint = QuartzJobEndPoint.class)
public class QuartzJobEndPointWebExtension {

private QuartzJobEndPoint qurtzJobEndPoint;

public QuartzJobEndPointWebExtension(QuartzJobEndPoint qurtzJobEndPoint) {
this.qurtzJobEndPoint = qurtzJobEndPoint;
}

@WriteOperation
public WebEndpointResponse<?> modifyJobStatus(@Selector String group, @Selector String name, @Selector String state)
throws SchedulerException {
try {
boolean isSucess = qurtzJobEndPoint.modifyJobStatus(group, name, state);
int status = isSucess ? WebEndpointResponse.STATUS_OK : WebEndpointResponse.STATUS_NOT_FOUND;
return new WebEndpointResponse<>(status);
} catch (UnsupportStateChangeException e) {
return new WebEndpointResponse<>(WebEndpointResponse.STATUS_BAD_REQUEST);
}
}
}

Quartz Trigger Endpoint

This endpoint is very similar to the Quartz job endpoint but works on trigger objects. The below endpoints will be useful:

GET /actuator/quartz-triggers?group=&name=
POST /actuator/quartz-triggers/{group}/{name}/pause
POST /actuator/quartz-triggers/{group}/{name}/resume

Let's see the code:

import java.util.Set;
import java.util.stream.Collectors;

import org.quartz.Scheduler;
import org.quartz.SchedulerException;
import org.quartz.Trigger;
import org.quartz.TriggerKey;
import org.quartz.impl.matchers.GroupMatcher;
import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
import org.springframework.boot.actuate.endpoint.annotation.Selector;
import org.springframework.boot.actuate.endpoint.annotation.WriteOperation;
import org.springframework.lang.Nullable;

import org.sathyabodh.actuator.quartz.exception.UnsupportStateChangeException;
import org.sathyabodh.actuator.quartz.model.GroupModel;
import org.sathyabodh.actuator.quartz.model.TriggerDetailModel;
import org.sathyabodh.actuator.quartz.service.TriggerModelBuilder;

@Endpoint(id = "quartz-triggers")
public class QuartzTriggerEndPoint {
private Scheduler scheduler;
private TriggerModelBuilder triggerModelBuilder = new TriggerModelBuilder();

public QuartzTriggerEndPoint(Scheduler scheduler) {
this.scheduler = scheduler;
}

@ReadOperation
public GroupModel<TriggerDetailModel> listTriggers(@Nullable String group, @Nullable String name)
throws SchedulerException {
try {
if (name != null && group != null) {
TriggerDetailModel model = triggerModelBuilder.buildTriggerDetailModel(scheduler,
new TriggerKey(name, group));
if (model == null) {
return null;
}
GroupModel<TriggerDetailModel> groupModel = new GroupModel<>();
groupModel.add(group, model);
return groupModel;
}
GroupMatcher<TriggerKey> triggerGroupMatcher = group == null ? GroupMatcher.anyTriggerGroup()
: GroupMatcher.triggerGroupEquals(group);
Set<TriggerKey> triggerKeys = scheduler.getTriggerKeys(triggerGroupMatcher);
if (name != null) {
triggerKeys = triggerKeys.stream().filter(key -> name.equals(key.getName()))
.collect(Collectors.toSet());
}
if (triggerKeys == null || triggerKeys.isEmpty()) {
return null;
}
GroupModel<TriggerDetailModel> groupModel = new GroupModel<>();
triggerKeys.forEach(key -> addTriggerDetailModel(groupModel, key));
return groupModel;
} catch (SchedulerException e) {
throw e;
}
}

private void addTriggerDetailModel(GroupModel<TriggerDetailModel> groupModel, TriggerKey key) {
TriggerDetailModel model;
try {
model = triggerModelBuilder.buildTriggerDetailModel(scheduler, key);
groupModel.add(key.getGroup(), model);
} catch (SchedulerException e) {
throw new RuntimeException(e);
}
}

@WriteOperation
public boolean modifyTriggerStatus(@Selector String group, @Selector String name, @Selector String state)
throws SchedulerException {
TriggerKey triggerKey = new TriggerKey(name, group);
Trigger trigger = scheduler.getTrigger(triggerKey);
if (trigger == null)
return false;
else if (QuartzState.PAUSE.equals(state)) {
scheduler.pauseTrigger(triggerKey);
} else if (QuartzState.RESUME.equals(state)) {
scheduler.resumeTrigger(triggerKey);
} else {
throw new UnsupportStateChangeException(String.format("unsupported state change. state:[%s]", state));
}
return true;
}

@WriteOperation
public boolean modifyTriggersStatus(@Selector String group, @Selector String state) throws SchedulerException {
GroupMatcher<TriggerKey> triggerGroupMatcher = GroupMatcher.triggerGroupEquals(group);
Set<TriggerKey> triggerKeys = scheduler.getTriggerKeys(triggerGroupMatcher);
if (triggerKeys == null || triggerKeys.isEmpty()) {
return false;
} else if (QuartzState.PAUSE.equals(state)) {
scheduler.pauseTriggers(triggerGroupMatcher);
} else if (QuartzState.RESUME.equals(state)) {
scheduler.resumeTriggers((triggerGroupMatcher));
} else {
throw new UnsupportStateChangeException(String.format("unsupported state change. state:[%s]", state));
}
return true;
}
}
-

And its web extension:

import org.quartz.SchedulerException;
import org.springframework.boot.actuate.endpoint.annotation.Selector;
import org.springframework.boot.actuate.endpoint.annotation.WriteOperation;
import org.springframework.boot.actuate.endpoint.web.WebEndpointResponse;
import org.springframework.boot.actuate.endpoint.web.annotation.EndpointWebExtension;

import org.sathyabodh.actuator.quartz.exception.UnsupportStateChangeException;

@EndpointWebExtension(endpoint = QuartzTriggerEndPoint.class)
public class QuartzTriggerEndPointWebExtension {

private QuartzTriggerEndPoint qurtzTriggerEndPoint;

public QuartzTriggerEndPointWebExtension(QuartzTriggerEndPoint qurtzTriggerEndPoint) {
this.qurtzTriggerEndPoint = qurtzTriggerEndPoint;
}

@WriteOperation
public WebEndpointResponse<?> modifyTriggerStatus(@Selector String group, @Selector String name,
@Selector String state) throws SchedulerException {
try {
boolean isSucess = qurtzTriggerEndPoint.modifyTriggerStatus(group, name, state);
int status = isSucess ? WebEndpointResponse.STATUS_OK : WebEndpointResponse.STATUS_NOT_FOUND;
return new WebEndpointResponse<>(status);
} catch (UnsupportStateChangeException e) {
return new WebEndpointResponse<>(WebEndpointResponse.STATUS_BAD_REQUEST);
}
}
}
-

Enabling Quartz Endpoints

These new endpoints can be enabled similar to out-of-the-box endpoints provided by the Spring Boot Actuator:

management.endpoints.web.exposure.include=quartz-jobs,quartz-triggers

These endpoint names are taken from id value specified in @EndPoint annotation.

Bonus: Spring Boot Autoconfigure Module

Now, we have looked at how to implement Quartz endpoint for the actuator. If we put the @Component annotation on top of each class, Spring will scan and register them. Now, Quartz can be managed just like any other entities supported by the out-of-the-box Spring Actuator. But we can do better. We can package all of these as an independent module and add autoconfigure feature. This makes it like any first-class Spring Boot autoconfigure module. When any application includes this jar as a dependency, and the Quartz scheduler dependency is also present, it will auto-register these endpoints.

Below is code for the autoconfigure feature:

import org.quartz.Scheduler;
import org.quartz.SchedulerFactory;
import org.springframework.boot.actuate.autoconfigure.endpoint.condition.ConditionalOnEnabledEndpoint;
import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.quartz.QuartzAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import org.sathyabodh.actuator.quartz.QuartzTriggerEndPoint;
import org.sathyabodh.actuator.quartz.QuartzTriggerEndPointWebExtension;

@Configuration
@ConditionalOnClass({ Scheduler.class, SchedulerFactory.class })
@AutoConfigureAfter(QuartzAutoConfiguration.class)
public class QuartzEndPointAutoConfiguration {

@Bean
@ConditionalOnMissingBean
@ConditionalOnEnabledEndpoint
public QuartzTriggerEndPoint quartzTriggerEndPoint(Scheduler scheduler) {
return new QuartzTriggerEndPoint(scheduler);
}

@Bean
@ConditionalOnBean(QuartzTriggerEndPoint.class)
public QuartzTriggerEndPointWebExtension quartzTriggerEndPointWebExtension(
QuartzTriggerEndPoint quartzTriggerEndPoint) {
return new QuartzTriggerEndPointWebExtension(quartzTriggerEndPoint);
}

@Bean
@ConditionalOnMissingBean
@ConditionalOnEnabledEndpoint
public QuartzTriggerEndPoint quartzTriggerEndPoint(Scheduler scheduler) {
return new QuartzTriggerEndPoint(scheduler);
}

@Bean
@ConditionalOnBean(QuartzTriggerEndPoint.class)
public QuartzTriggerEndPointWebExtension quartzTriggerEndPointWebExtension(
QuartzTriggerEndPoint quartzTriggerEndPoint) {
return new QuartzTriggerEndPointWebExtension(quartzTriggerEndPoint);
}
}
-

The last thing left now is to configure the class name in src/main/resources/META-INF/spring.factories file.

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
org.sathyabodh.actuator.autoconfigure.quartz.QurtzEndPointAutoConfiguration

Summary

Now, we have seen how to implement Quartz endpoints using Spring Actuator and also make the Spring Boot autoconfigure module for ease of use.