elastic-job入門例項
阿新 • • 發佈:2018-12-30
說明
Elastic-Job是一個分散式排程解決方案,由兩個相互獨立的子專案Elastic-Job-Lite和Elastic-Job-Cloud組成。
Elastic-Job-Lite定位為輕量級無中心化解決方案,使用jar包的形式提供分散式任務的協調服務;Elastic-Job-Cloud採用自研Mesos Framework的解決方案,額外提供資源治理、應用分發以及程序隔離等功能。
功能列表
1. 任務分片
- 將整體任務拆解為多個子任務
- 可通過伺服器的增減彈性伸縮任務處理能力
- 分散式協調,任務伺服器上下線的全自動發現與處理
2. 多工型別
- 基於時間驅動的任務
- 基於資料驅動的任務(TBD)
- 同時支援常駐任務和瞬時任務
- 多語言任務支援
3. 雲原生
- 完美結合Mesos或Kubernetes等排程平臺
- 任務不依賴於IP、磁碟、資料等有狀態元件
- 合理的資源排程,基於Netflix的Fenzo進行資源分配
4. 容錯性
- 支援定時自我故障檢測與自動修復
- 分散式任務分片唯一性保證
- 支援失效轉移和錯過任務重觸發
5. 任務聚合
- 相同任務聚合至相同的執行器統一處理
- 節省系統資源與初始化開銷
- 動態調配追加資源至新分配的任務
6. 易用性
- 完善的運維平臺
- 提供任務執行歷史資料追蹤能力
- 註冊中心資料一鍵dump用於備份與除錯問題
接下來我們就開始實現一個小例子
構建工具
gradle
專案結構如下
引入依賴
在build.gradle檔案中
//elastic-job
[group: 'com.dangdang', name: 'elastic-job-lite-core', version: '2.1.5'],
[group: 'com.dangdang', name: 'elastic-job-lite-spring', version: '2.1.5']
SimpleJob 簡單作業
import com.dangdang.ddframe.job.api.ShardingContext;
import com.dangdang.ddframe.job.api.simple.SimpleJob;
public class MyElasticSimpleJob implements SimpleJob{
@Override
public void execute(ShardingContext context) {
switch (context.getShardingItem()) {
case 0:
System.out.println("do something by sharding item 0");
break;
case 1:
System.out.println("do something by sharding item 1");
break;
case 2:
System.out.println("do something by sharding item 2");
break;
// case n: ...
}
}
}
DataFlowJob 資料流作業
import java.util.ArrayList;
import java.util.List;
import com.dangdang.ddframe.job.api.ShardingContext;
import com.dangdang.ddframe.job.api.dataflow.DataflowJob;
public class MyElasticDataflowJob implements DataflowJob<String>{
@Override
public List<String> fetchData(ShardingContext context) {
switch (context.getShardingItem()) {
case 0:
// get data from database by sharding item 0
List<String> data1 = new ArrayList<>();
data1.add("get data from database by sharding item 0");
return data1;
case 1:
// get data from database by sharding item 1
List<String> data2 = new ArrayList<>();
data2.add("get data from database by sharding item 1");
return data2;
case 2:
// get data from database by sharding item 2
List<String> data3 = new ArrayList<>();
data3.add("get data from database by sharding item 2");
return data3;
// case n: ...
}
return null;
}
@Override
public void processData(ShardingContext shardingContext, List<String> data) {
int count=0;
// process data
// ...
for (String string : data) {
count++;
System.out.println(string);
if (count>10) {
return;
}
}
}
}
測試以上兩種作業
import java.net.InetAddress;
import java.net.UnknownHostException;
import com.dangdang.ddframe.job.api.dataflow.DataflowJob;
import com.dangdang.ddframe.job.api.simple.SimpleJob;
import com.dangdang.ddframe.job.config.JobCoreConfiguration;
import com.dangdang.ddframe.job.config.JobRootConfiguration;
import com.dangdang.ddframe.job.config.dataflow.DataflowJobConfiguration;
import com.dangdang.ddframe.job.config.script.ScriptJobConfiguration;
import com.dangdang.ddframe.job.config.simple.SimpleJobConfiguration;
import com.dangdang.ddframe.job.lite.api.JobScheduler;
import com.dangdang.ddframe.job.lite.config.LiteJobConfiguration;
import com.dangdang.ddframe.job.reg.base.CoordinatorRegistryCenter;
import com.dangdang.ddframe.job.reg.zookeeper.ZookeeperConfiguration;
import com.dangdang.ddframe.job.reg.zookeeper.ZookeeperRegistryCenter;
import com.job.task.MyElasticDataflowJob;
import com.job.task.MyElasticSimpleJob;
public class JobDemo {
public static void main(String[] args) throws UnknownHostException {
System.out.println("Start...");
System.out.println(InetAddress.getLocalHost());
new JobScheduler(createRegistryCenter(), createSimpleJobConfiguration()).init();
new JobScheduler(createRegistryCenter(), createDataflowJobConfiguration()).init();
}
private static CoordinatorRegistryCenter createRegistryCenter() {
CoordinatorRegistryCenter regCenter = new ZookeeperRegistryCenter(
new ZookeeperConfiguration("127.0.0.1:2181", "new-elastic-job-demo"));
regCenter.init();
return regCenter;
}
private static LiteJobConfiguration createSimpleJobConfiguration() {
// 定義作業核心配置
JobCoreConfiguration simpleCoreConfig = JobCoreConfiguration.newBuilder("SimpleJobDemo", "0/15 * * * * ?", 10).build();
// 定義SIMPLE型別配置
SimpleJobConfiguration simpleJobConfig = new SimpleJobConfiguration(simpleCoreConfig, MyElasticSimpleJob.class.getCanonicalName());
// 定義Lite作業根配置
JobRootConfiguration simpleJobRootConfig = LiteJobConfiguration.newBuilder(simpleJobConfig).build();
return (LiteJobConfiguration) simpleJobRootConfig;
}
private static LiteJobConfiguration createDataflowJobConfiguration() {
// 定義作業核心配置
JobCoreConfiguration dataflowCoreConfig = JobCoreConfiguration.newBuilder("DataflowJob", "0/30 * * * * ?", 10).build();
// 定義DATAFLOW型別配置
DataflowJobConfiguration dataflowJobConfig = new DataflowJobConfiguration(dataflowCoreConfig, MyElasticDataflowJob.class.getCanonicalName(), true);
// 定義Lite作業根配置
JobRootConfiguration dataflowJobRootConfig = LiteJobConfiguration.newBuilder(dataflowJobConfig).build();
return (LiteJobConfiguration) dataflowJobRootConfig;
}
}
執行結果
現在我們通過配置檔案的方式來實現兩種型別的作業
建立elastic.xml配置檔案
將elastic-job通過配置檔案進行引數設定
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:reg="http://www.dangdang.com/schema/ddframe/reg"
xmlns:job="http://www.dangdang.com/schema/ddframe/job"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.dangdang.com/schema/ddframe/reg
http://www.dangdang.com/schema/ddframe/reg/reg.xsd
http://www.dangdang.com/schema/ddframe/job
http://www.dangdang.com/schema/ddframe/job/job.xsd
">
<!-- 配置作業註冊中心; baseSleepTimeMilliseconds:等待重試的間隔時間的初始值單位:毫秒 ;
maxSleepTimeMilliseconds:等待重試的間隔時間的最大值單位:毫秒;maxRetries:最大重試次數 -->
<reg:zookeeper id="regCenter" server-lists="192.168.6.175:12181"
namespace="elastic-job" base-sleep-time-milliseconds="1000"
max-sleep-time-milliseconds="3000" max-retries="3" />
<!-- 配置簡單作業 -->
<job:simple id="JobSimpleJob" class="com.job.task.MyElasticSimpleJob"
registry-center-ref="regCenter" cron="0/30 * * * * ?"
sharding-total-count="3" sharding-item-parameters="0=A,1=B,2=C" />
<!-- 配置資料流作業, job-parameter定義的為分頁引數
sharding-total-count 作業分片總數
sharding-item-parameters分片序列號和引數用等號分隔,多個鍵值對用逗號分隔 ,分片序列號從0開始,不可大於或等於作業分片總數
job-parameter 作業自定義引數,可通過傳遞該引數為作業排程的業務方法傳參,用於實現帶引數的作業
例:每次獲取的資料量、作業例項從資料庫讀取的主鍵等
job-sharding-strategy-class 作業分片策略實現類全路徑 預設使用平均分配策略
streaming-process 是否流式處理資料
reconcile-interval-minutes 修復作業伺服器不一致狀態服務排程間隔時間,配置為小於1的任意值表示不執行修復
event-trace-rdb-data-source 作業事件追蹤的資料來源Bean引用
-->
<job:dataflow id="JobDataflow" class="com.job.task.MqElasticDataflowJob"
registry-center-ref="regCenter" cron="0/10 * * * * ?" sharding-total-count="3"
sharding-item-parameters="0=a,1=b,2=c" job-sharding-strategy-class="com.dangdang.ddframe.job.lite.api.strategy.impl.AverageAllocationJobShardingStrategy"
job-parameter="100" streaming-process="true" reconcile-interval-minutes="10"
overwrite="true" event-trace-rdb-data-source="dataSource"/>
</beans>
配置datasource
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:util="http://www.springframework.org/schema/util"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
destroy-method="close">
<property name="driverClass" value="com.mysql.jdbc.Driver" />
<property name="jdbcUrl" value="jdbc:mysql://127.0.0.1:3306/for_test?useUnicode=yes&characterEncoding=UTF-8" />
<property name="user" value="admin" />
<property name="password" value="super" />
<property name="minPoolSize" value="3" />
<property name="maxPoolSize" value="20" />
<property name="acquireIncrement" value="1" />
<property name="testConnectionOnCheckin" value="true" />
<property name="maxIdleTimeExcessConnections" value="240" />
<property name="idleConnectionTestPeriod" value="300" />
</bean>
</beans>
建立applicationContext.xml檔案
將elastic-job與Spring整合
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context" xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd ">
<task:scheduler id="taskScheduler" pool-size="10" />
<task:executor id="taskExecutor" />
<task:annotation-driven executor="taskExecutor" scheduler="taskScheduler" />
<import resource="elastic.xml" />
<import resource="mysql.xml"/>
</beans>
配置web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<display-name>elastic-job</display-name>
<!-- 用來設定web應用的環境引數(context) -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:applicationContext.xml</param-value>
</context-param>
<!-- listener元素用來定義Listener介面,對事件監聽程式 -->
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
</web-app>