Scheduled jobs in Dropwizard using Sundial, a quartz fork.
Sundial makes adding scheduled jobs to your Java application a walk in the park. Simply define jobs, define triggers, and start the Sundial scheduler. dropwizard-sundial makes integrating and configuring the job scheduler into dropwizard a snap.
Add the dropwizard-sundial library as a dependency to your pom.xml
file:
<dependency>
<groupId>com.xeiam</groupId>
<artifactId>dropwizard-sundial</artifactId>
<version>0.8.1.0</version>
</dependency>
Add the Sundial bundle to the Dropwizard environment:
public void initialize(Bootstrap<MyApplicationConfiguration> bootstrap) {
bootstrap.addBundle(new SundialBundle<MyApplicationConfiguration>() {
@Override
public SundialConfiguration getSundialConfiguration(MyApplicationConfiguration configuration) {
return configuration.getSundialConfiguration();
}
});
}
Add the 'SundialConfiguration' to your application configuration class (MyApplicationConfiguration
):
@Valid
@NotNull
public SundialConfiguration sundialConfiguration = new SundialConfiguration();
@JsonProperty("sundial")
public SundialConfiguration getSundialConfiguration() {
return sundialConfiguration;
}
Edit you app's Dropwizard YAML config file (default values are shown below except for annotated-jobs-package-name
):
sundial:
thread-pool-size: 10
shutdown-on-unload: true
wait-on-shutdown: false
start-delay-seconds: 0
start-scheduler-on-load: true
global-lock-on-load: false
annotated-jobs-package-name: com.foo.bar.jobs
sundial:
annotated-jobs-package-name: com.foo.bar.jobs
public class SampleJob extends com.xeiam.sundial.Job {
@Override
public void doRun() throws JobInterruptException {
// Do something interesting...
}
}
@CronTrigger(cron = "0/5 * * * * ?")
@SimpleTrigger(repeatInterval = 30, timeUnit = TimeUnit.SECONDS)
If adding jobs and triggers this way, you should not use annotations.
<?xml version='1.0' encoding='utf-8'?>
<job-scheduling-data>
<schedule>
<!-- job with cron trigger -->
<job>
<name>SampleJob3</name>
<job-class>com.foo.bar.jobs.SampleJob3</job-class>
<concurrency-allowed>true</concurrency-allowed>
</job>
<trigger>
<cron>
<name>SampleJob3-Trigger</name>
<job-name>SampleJob3</job-name>
<cron-expression>*/15 * * * * ?</cron-expression>
</cron>
</trigger>
<!-- job with simple trigger -->
<job>
<name>SampleJob2</name>
<job-class>com.foo.bar.jobs.SampleJob2</job-class>
<job-data-map>
<entry>
<key>MyParam</key>
<value>42</value>
</entry>
</job-data-map>
</job>
<trigger>
<simple>
<name>SampleJob2-Trigger</name>
<job-name>SampleJob2</job-name>
<repeat-count>5</repeat-count>
<repeat-interval>5000</repeat-interval>
</simple>
</trigger>
</schedule>
</job-scheduling-data>
You may want access to a global object such as a REST client, and you don't want to have to reinstantiate that object every single time the job is run. It can be done quite easily by
putting the object in the ServletContext during app startup in the run
method. Since Sundial is bound to the ServletContext's lifecycle, it has direct access to the ServletContext.
The ServletContext has a String, Object
map for holding these global objects. The following code snippets show how to add an object to the ServletContext in the dropwizard run
method and how
to access it from a job.
@Override
public void run(XDropWizardApplicationConfiguration configuration, Environment environment) throws Exception {
logger.info("running DropWizard!");
// Add object to ServletContext for accessing from Sundial Jobs
environment.getApplicationContext().setAttribute("MyKey", "MyObject");
...
}
@CronTrigger(cron = "0/25 * * * * ?")
public class MyJob extends Job {
private final Logger logger = LoggerFactory.getLogger(MyJob.class);
@Override
public void doRun() throws JobInterruptException {
// pull object from ServletContext, which was added in the apllication's run method
String myObject = (String) SundialJobScheduler.getServletContext().getAttribute("MyKey");
logger.info("MyJob says: " + myObject);
}
}
curl -X POST http://localhost:9090/admin/tasks/locksundialscheduler
curl -X POST http://localhost:9090/admin/tasks/unlocksundialscheduler
curl -X POST "http://localhost:9090/admin/tasks/startjob?JOB_NAME=MyJob"
curl -X POST "http://localhost:9090/admin/tasks/startjob?JOB_NAME=SampleJob3&MyParam=9999"
curl -X POST "http://localhost:9090/admin/tasks/stopjob?JOB_NAME=SampleJob3"
curl -X POST "http://localhost:9090/admin/tasks/removejob?JOB_NAME=SampleJob3"
curl -X POST "http://localhost:9090/admin/tasks/addjob?JOB_NAME=SampleJob3&JOB_CLASS=com.xeiam.xdropwizard.jobs.SampleJob3&MyParam=888"
curl -X POST http://localhost:9090/admin/tasks/removejobtrigger?TRIGGER_NAME=SampleJob3-Trigger
curl -X POST "http://localhost:9090/admin/tasks/addcronjobtrigger?TRIGGER_NAME=SampleJob3-Trigger&JOB_NAME=SampleJob3&CRON_EXPRESSION=0/45%20*%20*%20*%20*%20?"
curl -X POST "http://localhost:9090/admin/tasks/addcronjobtrigger?TRIGGER_NAME=SampleJob3-Trigger&JOB_NAME=SampleJob3" --data-urlencode "CRON_EXPRESSION=0/45 * * * * ?"
Visit Sundial to find out more about the scheduler itself and XDropWizard to see a working example of a DropWizard app integrating Sundial via the dropwizard-sundial
project.