ElasticJob的作业分类基于class和type两种类型。基于class的作业需要开发者自行通过实现接口的方式织入业务逻辑；基于type的作业则无需编码，只需要提供相应配置即可。基于class的作业接口的方法参数shardingContext包含作业配置、片和运行时信息。可通过getShardingTotalCount()、getShardingItem()等方法分别获取分片总数和运行在本作业服务器的分片序列号等。
ElasticJob目前提供Simple、Dataflow这两种基于class的作业类型，并提供Script、HTTP这两种基于type的作业类型，用户可通过实现SPI接口自行扩展作业类型。
本篇博客介绍HTTP作业。
添加依赖（3.0.1是目前最新的Releases版本）：
<dependency><groupId>org.apache.shardingsphere.elasticjob</groupId><artifactId>elasticjob-lite-core</artifactId><version>3.0.1</version></dependency>
HTTP作业
先搭建一个Spring Boot项目，在项目中定义一个接口。
pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>com.kaven</groupId><artifactId>server</artifactId><packaging>pom</packaging><version>1.0-SNAPSHOT</version><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.3.2.RELEASE</version></parent><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency></dependencies>
</project>
MessageController接口定义：
package com.kaven.controller;import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RestController;import java.text.SimpleDateFormat;
import java.util.Date;/*** @Author: ITKaven* @Date: 2021/12/06 19:29* @Blog: https://kaven.blog.csdn.net* @Leetcode: https://leetcode-cn.com/u/kavenit* @Notes:*/@RestController
public class MessageController {
private static final SimpleDateFormat formatter =new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");private static final String MESSAGE_HEAD = "MessageController";@GetMapping("/message")public String getMessage(String messageBody, @RequestHeader String shardingContext) {
String message = MESSAGE_HEAD + " " + messageBody;System.out.println(formatter.format(new Date()) + " " + message + " - " + shardingContext);return message;}
}
Server启动类：
package com.kaven;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;/*** @Author: ITKaven* @Date: 2021/12/06 19:28* @Blog: https://kaven.blog.csdn.net* @Leetcode: https://leetcode-cn.com/u/kavenit* @Notes:*/@SpringBootApplication
public class Server {
public static void main(String[] args) {
SpringApplication.run(Server.class);}
}
Application类：
package com.kaven.job;import org.apache.shardingsphere.elasticjob.api.JobConfiguration;
import org.apache.shardingsphere.elasticjob.http.props.HttpJobProperties;
import org.apache.shardingsphere.elasticjob.lite.api.bootstrap.impl.ScheduleJobBootstrap;
import org.apache.shardingsphere.elasticjob.reg.base.CoordinatorRegistryCenter;
import org.apache.shardingsphere.elasticjob.reg.zookeeper.ZookeeperConfiguration;
import org.apache.shardingsphere.elasticjob.reg.zookeeper.ZookeeperRegistryCenter;/*** @Author: ITKaven* @Date: 2021/11/20 17:05* @Blog: https://kaven.blog.csdn.net* @Leetcode: https://leetcode-cn.com/u/kavenit* @Notes:*/
public class Application {
public static void main(String[] args) {
new ScheduleJobBootstrap(createRegistryCenter(), "HTTP",createJobConfiguration()).schedule();}private static CoordinatorRegistryCenter createRegistryCenter() {
ZookeeperConfiguration zc = new ZookeeperConfiguration("192.168.1.184:9000", "my-job");zc.setConnectionTimeoutMilliseconds(40000);zc.setMaxRetries(5);CoordinatorRegistryCenter regCenter = new ZookeeperRegistryCenter(zc);regCenter.init();return regCenter;}private static JobConfiguration createJobConfiguration() {
return JobConfiguration.newBuilder("MyHTTPJob", 3).description("HTTP作业").cron("30 * * * * ?").setProperty(HttpJobProperties.URI_KEY, "http://localhost:8080/message?messageBody=MyHTTPJob").setProperty(HttpJobProperties.METHOD_KEY, "GET")
// .setProperty(HttpJobProperties.DATA_KEY, "messageBody=MyHTTPJob").overwrite(true).failover(true).build();}
}
定义HTTP作业也比较简单，只需要设置HTTP作业的相关参数，比如接口的URI、类型、参数以及连接超时时间等，HttpJobProperties.DATA_KEY用于给POST这类请求设置参数。
.setProperty(HttpJobProperties.URI_KEY, "http://localhost:8080/message?messageBody=MyHTTPJob").setProperty(HttpJobProperties.METHOD_KEY, "GET")
// .setProperty(HttpJobProperties.DATA_KEY, "messageBody=MyHTTPJob")
HttpJobProperties类：
package org.apache.shardingsphere.elasticjob.http.props;/*** HTTP job properties.*/
public final class HttpJobProperties {
public static final String URI_KEY = "http.uri";public static final String METHOD_KEY = "http.method";public static final String DATA_KEY = "http.data";public static final String CONNECT_TIMEOUT_KEY = "http.connect.timeout.milliseconds";public static final String READ_TIMEOUT_KEY = "http.read.timeout.milliseconds";public static final String CONTENT_TYPE_KEY = "http.content.type";public static final String SHARDING_CONTEXT_KEY = "shardingContext";
}
输出如下图所示：
多参数接口
如果GET接口有多个参数，在URI上进行拼接即可。
.setProperty(HttpJobProperties.URI_KEY, "http://localhost:8080/message?arg1=1&arg2=2")
而如果是POST接口有多个参数，就不能多次调用setProperty(HttpJobProperties.DATA_KEY, "key=value")来完成多个参数的传值，因为值会被覆盖（即只会取最后一次设置的值，ElasticJob使用Java的Properties来存储参数，而Properties继承Hashtable，当键相同时，值会被覆盖，而参数的键都是HttpJobProperties.DATA_KEY）。
private static JobConfiguration createJobConfiguration() {
return JobConfiguration.newBuilder("MyHTTPJob", 3).description("HTTP作业").cron("30 * * * * ?").setProperty(HttpJobProperties.URI_KEY, "http://localhost:8080/message").setProperty(HttpJobProperties.METHOD_KEY, "POST").setProperty(HttpJobProperties.DATA_KEY, "arg1=1").setProperty(HttpJobProperties.DATA_KEY, "arg2=2").overwrite(true).failover(true).build();}
接口：
package com.kaven.controller;import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;/*** @Author: ITKaven* @Date: 2021/12/06 19:29* @Blog: https://kaven.blog.csdn.net* @Leetcode: https://leetcode-cn.com/u/kavenit* @Notes:*/@RestController
public class MessageController {
@PostMapping("/message")public void getMessage(String arg1, String arg2) {
System.out.println(arg1 + arg2);}
}
输出如下图所示：
第一个参数被覆盖了，所以为null，因此给POST接口传多个参数，博主想到的方法是将多个参数组合成一个实例，再将其转换成JSON字符串，接口那边再将这个JSON字符串转换成对应的实例。大家如果有更好的方法可以评论区留言。
添加依赖：
<dependency><groupId>com.google.code.gson</groupId><artifactId>gson</artifactId><version>2.8.9</version></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.22</version><scope>provided</scope></dependency>
存储多个参数的Data类：
package com.kaven.job.data;import lombok.*;/*** @Author: ITKaven* @Date: 2021/12/07 14:33* @Blog: https://kaven.blog.csdn.net* @Leetcode: https://leetcode-cn.com/u/kavenit* @Notes:*/@Setter
@AllArgsConstructor
@NoArgsConstructor
@Builder
@ToString
public class Data {
private String username;private String password;private School school;@Setter@AllArgsConstructor@NoArgsConstructor@Builder@ToStringpublic static class School{
private String name;private String address;}
}
Application类：
package com.kaven.job;import com.google.gson.Gson;
import com.kaven.job.data.Data;
import org.apache.shardingsphere.elasticjob.api.JobConfiguration;
import org.apache.shardingsphere.elasticjob.http.props.HttpJobProperties;
import org.apache.shardingsphere.elasticjob.lite.api.bootstrap.impl.ScheduleJobBootstrap;
import org.apache.shardingsphere.elasticjob.reg.base.CoordinatorRegistryCenter;
import org.apache.shardingsphere.elasticjob.reg.zookeeper.ZookeeperConfiguration;
import org.apache.shardingsphere.elasticjob.reg.zookeeper.ZookeeperRegistryCenter;/*** @Author: ITKaven* @Date: 2021/11/20 17:05* @Blog: https://kaven.blog.csdn.net* @Leetcode: https://leetcode-cn.com/u/kavenit* @Notes:*/
public class Application {
public static void main(String[] args) {
new ScheduleJobBootstrap(createRegistryCenter(), "HTTP",createJobConfiguration()).schedule();}private static CoordinatorRegistryCenter createRegistryCenter() {
ZookeeperConfiguration zc = new ZookeeperConfiguration("192.168.1.184:9000", "my-job");zc.setConnectionTimeoutMilliseconds(40000);zc.setMaxRetries(5);CoordinatorRegistryCenter regCenter = new ZookeeperRegistryCenter(zc);regCenter.init();return regCenter;}private static JobConfiguration createJobConfiguration() {
Data data = Data.builder().username("kaven").password("itkaven").school(Data.School.builder().name("xxx").address("中国").build()).build();String dataStr = (new Gson()).toJson(data);System.out.println(dataStr);return JobConfiguration.newBuilder("MyHTTPJob", 3).description("HTTP作业").cron("30 * * * * ?").setProperty(HttpJobProperties.URI_KEY, "http://localhost:8080/message").setProperty(HttpJobProperties.METHOD_KEY, "POST").setProperty(HttpJobProperties.DATA_KEY, "args=" + dataStr).overwrite(true).failover(true).build();}
}
下面这部分就是将要传的多个参数组合成Data实例，然后再将其转换成JSON字符串。
Data data = Data.builder().username("kaven").password("itkaven").school(Data.School.builder().name("xxx").address("中国").build()).build();String dataStr = (new Gson()).toJson(data);
接口（将JSON字符串再转换成想要的包含多个参数信息的Data实例）：
package com.kaven.controller;import com.google.gson.Gson;
import com.kaven.data.Data;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestHeader;
import org.springframework.web.bind.annotation.RestController;import java.text.SimpleDateFormat;
import java.util.Date;/*** @Author: ITKaven* @Date: 2021/12/06 19:29* @Blog: https://kaven.blog.csdn.net* @Leetcode: https://leetcode-cn.com/u/kavenit* @Notes:*/@RestController
public class MessageController {
private static final SimpleDateFormat formatter =new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");private static final String MESSAGE_HEAD = "MessageController";@PostMapping("/message")public void getMessage(String args, @RequestHeader String shardingContext) {
Gson gson = new Gson();Data data = gson.fromJson(args, Data.class);System.out.println(formatter.format(new Date()) + " " + data + " " + shardingContext);}
}
输出如下图所示：
HTTP作业就介绍到这里，如果博主有说错的地方或者大家有不同的见解，欢迎大家评论补充。