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Spring动态切换数据源
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11
//定义数据源枚举
public enum DataSourceKey {
master,
slave,
}
22
/**
* 数据源路由
*/
@Slf4j
public class DynamicRoutingDataSource extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
log.error("Current DataSource is [{}]", DynamicDataSourceContextHolder.getDataSourceKey());
return DynamicDataSourceContextHolder.getDataSourceKey();
} }
/**
* 数据源路由holder
*/
@Slf4j
public class DynamicDataSourceContextHolder {
private static int counter = 0; private static final ThreadLocal<String> CONTEXT_HOLDER = ThreadLocal.withInitial(DataSourceKey.master::name); /**
* 所有数据源key
*/
public static List<Object> dataSourceKeys = new ArrayList<>(); /**
* 从数据源key
*/
public static List<Object> slaveDataSourceKeys = new ArrayList<>(); /**
*
* set数据源
*/
public static void setDataSourceKey(String key) {
CONTEXT_HOLDER.set(key);
} /**
* get数据源
*/
public static String getDataSourceKey() {
return CONTEXT_HOLDER.get();
}
/**
* 主数据源
*/
public static void useMasterDataSource() {
CONTEXT_HOLDER.set(DataSourceKey.master.name());
} /**
* 从数据源
*/
public static void useSlaveDataSource() {
try {
int datasourceKeyIndex = counter % slaveDataSourceKeys.size();//负载均衡-轮询
CONTEXT_HOLDER.set(String.valueOf(slaveDataSourceKeys.get(datasourceKeyIndex)));
counter++;
} catch (Exception e) {
log.error("Switch slave datasource failed, error message is {}", e.getMessage());
useMasterDataSource();
e.printStackTrace();
}
} public static void clearDataSourceKey() {
CONTEXT_HOLDER.remove();
} public static boolean containDataSourceKey(String key) {
return dataSourceKeys.contains(key);
} }
33
@Configuration
@MapperScan(basePackages = "com.buyi.mytransaction.dao.one", sqlSessionFactoryRef = "mybatisSqlSessionFactoryOne")
public class MyDynamicMybatisDataSource { @Bean(name = "master")
@Primary
@ConfigurationProperties(prefix = "spring.datasource.one.master", ignoreInvalidFields = true)
public DataSource master() {
return new DruidDataSource();
} @Bean(name = "slave")
@ConfigurationProperties(prefix = "spring.datasource.one.slave", ignoreInvalidFields = true)
public DataSource slave() {
return new DruidDataSource();
} @Bean("dynamicDataSource")
public DataSource dynamicDataSource() {
DynamicRoutingDataSource dynamicRoutingDataSource = new DynamicRoutingDataSource();
Map<Object, Object> dataSourceMap = new HashMap<>(4);
dataSourceMap.put(DataSourceKey.master.name(), master());
dataSourceMap.put(DataSourceKey.slave.name(), slave()); dynamicRoutingDataSource.setDefaultTargetDataSource(master());//默认数据源
dynamicRoutingDataSource.setTargetDataSources(dataSourceMap);//数据源 DynamicDataSourceContextHolder.dataSourceKeys.addAll(dataSourceMap.keySet());//所有数据源
DynamicDataSourceContextHolder.slaveDataSourceKeys.addAll(dataSourceMap.keySet());//设置从数据源
DynamicDataSourceContextHolder.slaveDataSourceKeys.remove(DataSourceKey.master.name());
return dynamicRoutingDataSource;
} //事务管理器
@Bean(name = "mybatisTransactionManagerOne")
@Primary
public DataSourceTransactionManager mybatisTransactionManager(@Qualifier("dynamicDataSource") DataSource dataSource) throws Exception {
return new DataSourceTransactionManager(dataSource);
} //会话工厂
@Bean("mybatisSqlSessionFactoryOne")
@Primary
public SqlSessionFactory mybatisSqlSessionFactory(@Qualifier("dynamicDataSource") DataSource dataSource) throws Exception {
SqlSessionFactoryBean sf = new SqlSessionFactoryBean();
sf.setDataSource(dataSource);
sf.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:repository/one/**/*Mapper.xml")); //自动转驼峰 resultType="***"
org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();
configuration.setMapUnderscoreToCamelCase(true);
sf.setConfiguration(configuration);
return sf.getObject();
} }
44
@Slf4j
@Aspect
@Component
public class DynamicDataSourceAspect { private final String[] QUERY_PREFIX = {"select","query"}; @Pointcut("execution( * com.buyi.mytransaction.dao.one.*.*(..))")
public void daoAspect() {
} /**
* 切换数据源
*/
@Before("daoAspect()")
public void switchDataSource(JoinPoint point) {
Boolean isQueryMethod = isQueryMethod(point.getSignature().getName());
if (isQueryMethod) {
DynamicDataSourceContextHolder.useSlaveDataSource();
log.debug("Switch DataSource to [{}] in Method [{}]",
DynamicDataSourceContextHolder.getDataSourceKey(), point.getSignature());
}
} /**
* 重置数据源
*/
@After("daoAspect())")
public void restoreDataSource(JoinPoint point) {
DynamicDataSourceContextHolder.clearDataSourceKey();
log.debug("Restore DataSource to [{}] in Method [{}]",
DynamicDataSourceContextHolder.getDataSourceKey(), point.getSignature());
} private Boolean isQueryMethod(String methodName) {
for (String prefix : QUERY_PREFIX) {
if (methodName.startsWith(prefix)) {
return true;
}
}
return false;
}
}
@Test
//测试切换数据源
public void test3() {
Company c = Company.builder().companyId("789").companyName("百度").memo("人工智能").build();
oneCompanyservice.oneInsert(c); List<Company> companyList = oneCompanyservice.selectAll();
for (Company company : companyList) {
System.out.println(company);
//Company(companyId=999, companyName=百度子公司, memo=111)
//此条数据在从数据库中已存在
}
}
