SpringBoot+Mybatis-Plus项目配置MySQL+SqlServer两种数据库并且动态修改SqlServer的IP和数据库名
一 需求
通过mysql上的数据库获取到各个服务器的IP地址和服务器名称，然后点击哪个服务器的ip就连接哪个服务器上面的SqlServer数据库，获取上面的数据。
主要参考资料
https://blog.csdn.net/qq_29752857/article/details/120214853 动态添加移除数据源
https://blog.csdn.net/liadc/article/details/108273358 mybatis项目配置多个数据库
二 开始
1.添加依赖
除SpringBoot+MybatisPlus需要的基本依赖，还需添加下面的依赖
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>dynamic-datasource-spring-boot-starter</artifactId>
<version>3.3.2</version>
</dependency>
2.修改application.yml文件的配置
# 数据库
spring:
datasource:
dynamic:
primary: exam #设置主库
strict: false # 设置false 连接失败默认连主库
datasource:
exam: #主库
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://127.0.0.1:3306/exam?useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai&useSSL=false
username: root
password: 123456
netexam: # 副库
driver-class-name: com.microsoft.sqlserver.jdbc.SQLServerDriver
url: jdbc:sqlserver://127.0.0.1:1433;DatabaseName=netExam
username: sa
password: sa
3.给对应业务层的方法添加注解
其中配置了两个数据源，exam与netexam，将exam设置为主库，如果对应的业务层方法未加@DS注解，则默认使用exam主库,如果想切换为副库netexam.可在整个service层或对应的方法上加注解并加上对应的数据源名称，例如@DS(“netexam”)。
@Service
@DS("netexam")
public class CourseService {
@Autowired
ChangeDBUtils changeDBUtils;
@Autowired
private SubjectMapper subjectMapper;
@DS("netexam")
public JSONObject test(String ip) {
JSONObject json = new JSONObject();
json = ExceptionUtils.setResultMsg(json, ExceptionUtils.SUCCESS);
changeDBUtils.changDatabase(ip,"netExam");
//查询subject
QueryWrapper<Subject> subjectQueryWrapper = new QueryWrapper<>();
List<Subject> list = subjectMapper.selectList(subjectQueryWrapper);
json.put("data", list);
return json;
}
}
4.增加动态修改数据库的实体类
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;
import javax.validation.constraints.NotBlank;
@Data
public class DataSourceDTO {
@NotBlank
@ApiModelProperty(value = "连接池名称", example = "db1")
private String poolName;
@NotBlank
@ApiModelProperty(value = "JDBC driver", example = "com.mysql.cj.jdbc.Driver")
private String driverClassName;
@NotBlank
@ApiModelProperty(value = "JDBC url 地址", example = "jdbc:mysql://x.x.x.x:3306/x?useUnicode=true&characterEncoding=utf-8")
private String url;
@NotBlank
@ApiModelProperty(value = "JDBC 用户名", example = "sa")
private String username;
@ApiModelProperty(value = "JDBC 密码")
private String password;
private String ip;
private String name;
}
5.增加获取Spring的bean的配置类
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
import java.util.Map;
@Component
public class SpringUtils implements ApplicationContextAware {
private static ApplicationContext applicationContext;
@Override
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
SpringUtils.applicationContext = applicationContext;
}
public static <T> T getBean(String beanName) {
if(applicationContext.containsBean(beanName)){
return (T) applicationContext.getBean(beanName);
}else{
return null;
}
}
public static <T> Map<String, T> getBeansOfType(Class<T> baseType){
return applicationContext.getBeansOfType(baseType);
}
public static ApplicationContext getApplicationContext() {
return applicationContext;
}
}
6.添加更换数据库工具类
首先先在application.yml增加参数，然后可根据传的ip地址和数据库名更换数据库
database.net.poolname: netexam
database.net.driverclassname: com.microsoft.sqlserver.jdbc.SQLServerDriver
database.net.username: sa
database.net.password: sa
@Component
public class ChangeDBUtils {
@Value("${database.net.poolname}")
private String poolName;
@Value("${database.net.driverclassname}")
private String driverClassName;
@Value("${database.net.username}")
private String username;
@Value("${database.net.password}")
private String password;
/** * @Description: 改变数据源 * @Date 2022/3/16 10:40 * @Param: ip 地址 name 数据源名字 * @return */
@DS("netexam")
public void changDatabase(String ip, String name) {
DataSourceDTO dto = new DataSourceDTO();
//获取数据源bean
DynamicRoutingDataSource ds = (DynamicRoutingDataSource) SpringUtil.getBean("dataSource");
//删除当前需更换数据源 根据数据源名 netexam
ds.removeDataSource(poolName); // 数据源名字
//添加新的数据源 需更换的SqlServer数据库
dto.setPoolName(poolName);
//仅修改SqlServer数据源 mysql需改参数
dto.setDriverClassName(driverClassName);
dto.setUrl("jdbc:sqlserver://"+ip+":1433;DatabaseName="+name);
dto.setUsername(username);
dto.setPassword(password);
DataSourceProperty dataSourceProperty = new DataSourceProperty();
BeanUtils.copyProperties(dto, dataSourceProperty);
DefaultDataSourceCreator dataSourceCreator = (DefaultDataSourceCreator) SpringUtil.getBean("dataSourceCreator");
DataSource dataSource = dataSourceCreator.createDataSource(dataSourceProperty);
ds.addDataSource(dto.getPoolName(), dataSource);
}
7.在Service层通过调用更改数据库的方法进行动态更改数据库
@Service
@DS("netexam")
public class CourseService {
//
@Autowired
ChangeDBUtils changeDBUtils;
@Autowired
private SubjectMapper subjectMapper;
@DS("netexam")
public JSONObject test(String ip) {
JSONObject json = new JSONObject();
json = ExceptionUtils.setResultMsg(json, ExceptionUtils.SUCCESS);
//可通过传的ip和数据库名称进行更换数据库
changeDBUtils.changDatabase(ip,"netExam");
//查询subject
QueryWrapper<Subject> subjectQueryWrapper = new QueryWrapper<>();
List<Subject> list = subjectMapper.selectList(subjectQueryWrapper);
json.put("data", list);
return json;
}
}
如果需要动态更换mysql数据库，与之同理，只需在application.yml将配置更换为mysql的配置即可。
