ElasticJob-Lite provides a customized Spring Boot Starter, which can be used in conjunction with Spring Boot. Developers are free from configuring CoordinatorRegistryCenter, JobBootstrap by using ElasticJob Spring Boot Starter. What developers need to solve distributed scheduling problem are job implementations with a little configuration.

Job configuration

Implements ElasticJob

Job implementation is similar to other usage of ElasticJob. The difference is that jobs will be registered into the Spring IoC container.

Thread-Safety Issue

Bean is singleton by default. Consider setting Bean Scope to prototype if the instance of ElasticJob would be used by more than a JobBootstrap.

@Component
public class SpringBootDataflowJob implements DataflowJob<Foo> {
    @Override
    public List<Foo> fetchData(final ShardingContext shardingContext) {
        // fetch data
    }
    @Override
    public void processData(final ShardingContext shardingContext, final List<Foo> data) {
        // process data
    }
}

Configure CoordinateRegistryCenter and Jobs

Configure the Zookeeper which will be used by ElasticJob via configuration files.

elasticjob.jobs is a Map. Using key as job name. Specific job type and configuration in value. The Starter will create instances of OneOffJobBootstrap or ScheduleJobBootstrap and register them into the Spring IoC container automatically.

Configuration reference:

elasticjob:
  regCenter:
    serverLists: localhost:6181
    namespace: elasticjob-lite-springboot
  jobs:
    dataflowJob:
      elasticJobClass: org.apache.shardingsphere.elasticjob.dataflow.job.DataflowJob
      cron: 0/5 * * * * ?
      shardingTotalCount: 3
      shardingItemParameters: 0=Beijing,1=Shanghai,2=Guangzhou
    scriptJob:
      elasticJobType: SCRIPT
      cron: 0/10 * * * * ?
      shardingTotalCount: 3
      props:
        script.command.line: "echo SCRIPT Job: "

Job Start

Schedule Job

Just start Spring Boot Starter directly. The schedule jobs will startup when the Spring Boot Application is started.

One-off Job

When to execute OneOffJob is up to you. Developers can inject the OneOffJobBootstrap bean into where they plan to invoke. Trigger the job by invoking execute() method manually.

The bean name of OneOffJobBootstrap is specified by property “jobBootstrapBeanName”, Please refer to Spring Boot Starter Configuration.

elasticjob:
  jobs:
    myOneOffJob:
      jobBootstrapBeanName: myOneOffJobBean
      ....

@RestController
public class OneOffJobController {
    // Inject via "@Resource"
    @Resource(name = "myOneOffJobBean")
    private OneOffJobBootstrap myOneOffJob;
    @GetMapping("/execute")
    public String executeOneOffJob() {
        myOneOffJob.execute();
        return "{\"msg\":\"OK\"}";
    }
    // Inject via "@Autowired"
    @Autowired
    @Qualifier(name = "myOneOffJobBean")
    private OneOffJobBootstrap myOneOffJob2;
    @GetMapping("/execute2")
    public String executeOneOffJob2() {
        myOneOffJob2.execute();
        return "{\"msg\":\"OK\"}";
    }
}

Configuration error handler strategy

In the process of using ElasticJob-Lite, when the job is abnormal, the following error handling strategies can be used.

Log Strategy

elasticjob:
  regCenter:
    ...
  jobs:
    ...
    jobErrorHandlerType: LOG

Throw Strategy

elasticjob:
  regCenter:
    ...
  jobs:
    ...
    jobErrorHandlerType: THROW

Ignore Strategy

elasticjob:
  regCenter:
    ...
  jobs:
    ...
    jobErrorHandlerType: IGNORE

Email Notification Strategy

Please refer to here for more details.

Maven POM:

<dependency>
    <groupId>org.apache.shardingsphere.elasticjob</groupId>
    <artifactId>elasticjob-error-handler-email</artifactId>
    <version>${latest.release.version}</version>
</dependency>

elasticjob:
  regCenter:
    ...
  jobs:
    ...
    jobErrorHandlerType: EMAIL 
  props:
    email:
      host: host
      port: 465
      username: username
      password: password
      useSsl: true
      subject: ElasticJob error message
      from: from@xxx.xx
      to: to1@xxx.xx,to2@xxx.xx
      cc: cc@xxx.xx
      bcc: bcc@xxx.xx
      debug: false

Wechat Enterprise Notification Strategy

Please refer to here for more details.

Maven POM:

<dependency>
    <groupId>org.apache.shardingsphere.elasticjob</groupId>
    <artifactId>elasticjob-error-handler-wechat</artifactId>
    <version>${latest.release.version}</version>
</dependency>

elasticjob:
  regCenter:
    ...
  jobs:
    ...
    jobErrorHandlerType: WECHAT 
  props:
    wechat:
      webhook: you_webhook
      connectTimeout: 3000
      readTimeout: 5000

Dingtalk Notification Strategy

Please refer to here for more details.

Maven POM:

<dependency>
    <groupId>org.apache.shardingsphere.elasticjob</groupId>
    <artifactId>elasticjob-error-handler-dingtalk</artifactId>
    <version>${latest.release.version}</version>
</dependency>

elasticjob:
  regCenter:
    ...
  jobs:
    ...
    jobErrorHandlerType: DINGTALK 
  props:
    dingtalk:
       webhook: you_webhook
       keyword: you_keyword
       secret: you_secret
       connectTimeout: 3000
       readTimeout: 5000