Explanation: This is mainly to read the documents of the shardingSphere course of Mr. Shang Silicon Valley Huanhuan, and record it. On the basis of her master-slave construction, I plan to implement a set of mysql master-slave + redis sentinel cluster + canal + local cache. Sort these out together.
This blog is based on the previous one, and it is written next. If you need to build a mysql master-slave, you can refer to the previous one
Build mysql master-slave based on docker
1. Create a SpringBoot program
1.1. Create a project
Project Type: Spring Initializr
SpringBoot scaffolding: http://start.aliyun.com
Project name: sharding-jdbc-demo
SpringBoot version: 2.3.7.RELEASE
1.2. Add dependencies
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.apache.shardingsphere</groupId>
<artifactId>shardingsphere-jdbc-core-spring-boot-starter</artifactId>
<version>5.1.1</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.3.1</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
1.3. Create entity class
package com.atguigu.shardingjdbcdemo.entity;
@TableName("t_user")
@Data
public class User {
@TableId(type = IdType.AUTO)
private Long id;
private String uname;
}
1.4. Create Mapper
package com.atguigu.shardingjdbcdemo.mapper;
@Mapper
public interface UserMapper extends BaseMapper<User> {
}
1.5. Configure read-write separation
application.properties：
# 应用名称
spring.application.name=sharging-jdbc-demo
# 开发环境设置
spring.profiles.active=dev
# 内存模式
spring.shardingsphere.mode.type=Memory
# 配置真实数据源
spring.shardingsphere.datasource.names=master,slave1,slave2
# 配置第 1 个数据源
spring.shardingsphere.datasource.master.type=com.zaxxer.hikari.HikariDataSource
spring.shardingsphere.datasource.master.driver-class-name=com.mysql.jdbc.Driver
spring.shardingsphere.datasource.master.jdbc-url=jdbc:mysql://192.168.100.201:3306/db_user
spring.shardingsphere.datasource.master.username=root
spring.shardingsphere.datasource.master.password=123456
# 配置第 2 个数据源
spring.shardingsphere.datasource.slave1.type=com.zaxxer.hikari.HikariDataSource
spring.shardingsphere.datasource.slave1.driver-class-name=com.mysql.jdbc.Driver
spring.shardingsphere.datasource.slave1.jdbc-url=jdbc:mysql://192.168.100.201:3307/db_user
spring.shardingsphere.datasource.slave1.username=root
spring.shardingsphere.datasource.slave1.password=123456
# 配置第 3 个数据源
spring.shardingsphere.datasource.slave2.type=com.zaxxer.hikari.HikariDataSource
spring.shardingsphere.datasource.slave2.driver-class-name=com.mysql.jdbc.Driver
spring.shardingsphere.datasource.slave2.jdbc-url=jdbc:mysql://192.168.100.201:3308/db_user
spring.shardingsphere.datasource.slave2.username=root
spring.shardingsphere.datasource.slave2.password=123456
# 读写分离类型，如: Static，Dynamic
spring.shardingsphere.rules.readwrite-splitting.data-sources.myds.type=Static
# 写数据源名称
spring.shardingsphere.rules.readwrite-splitting.data-sources.myds.props.write-data-source-name=master
# 读数据源名称，多个从数据源用逗号分隔
spring.shardingsphere.rules.readwrite-splitting.data-sources.myds.props.read-data-source-names=slave1,slave2
# 负载均衡算法名称
spring.shardingsphere.rules.readwrite-splitting.data-sources.myds.load-balancer-name=alg_round
# 负载均衡算法配置
# 负载均衡算法类型
spring.shardingsphere.rules.readwrite-splitting.load-balancers.alg_round.type=ROUND_ROBIN
spring.shardingsphere.rules.readwrite-splitting.load-balancers.alg_random.type=RANDOM
spring.shardingsphere.rules.readwrite-splitting.load-balancers.alg_weight.type=WEIGHT
spring.shardingsphere.rules.readwrite-splitting.load-balancers.alg_weight.props.slave1=1
spring.shardingsphere.rules.readwrite-splitting.load-balancers.alg_weight.props.slave2=2
# 打印SQl
spring.shardingsphere.props.sql-show=true
2. Test
2.1, read and write separation test
package com.atguigu.shardingjdbcdemo;
@SpringBootTest
class ReadwriteTest {
@Autowired
private UserMapper userMapper;
/**
* 写入数据的测试
*/
@Test
public void testInsert(){
User user = new User();
user.setUname("张三丰");
userMapper.insert(user);
}
}
2.2. Transaction test
In order to ensure the transaction consistency between master and slave databases and avoid cross-service distributed transactions, ShardingSphere-JDBC is used 主从模型中，事务中的数据读写均用主库.
- Do not add @Transactional: insert operates on the master library, select operates on the slave library
- Add @Transactional: both insert and select operate on the main library
- **Note: **The @Transactional annotation in the JUnit environment will roll back the transaction by default (even if @Rollback is not annotated, the transaction will be rolled back)
/**
* 事务测试
*/
@Transactional//开启事务
@Test
public void testTrans(){
User user = new User();
user.setUname("铁锤");
userMapper.insert(user);
List<User> users = userMapper.selectList(null);
}
2.3. Load balancing test
/**
* 读数据测试
*/
@Test
public void testSelectAll(){
List<User> users = userMapper.selectList(null);
List<User> users = userMapper.selectList(null);//执行第二次测试负载均衡
users.forEach(System.out::println);
}
You can also test load balancing in web requests
package com.atguigu.shardingjdbcdemo.controller;
@RestController
@RequestMapping("/userController")
public class UserController {
@Autowired
private UserMapper userMapper;
/**
* 测试负载均衡策略
*/
@GetMapping("selectAll")
public void selectAll(){
List<User> users = userMapper.selectList(null);
users.forEach(System.out::println);
}
}