JAVA：Springboot动态装配Druid多数据源
1、简介
最近打算搭建一个鉴权中心服务，采用springboot+FastMybatis装配Druid，考虑后续拓展采用Druid多数据源配置，以一个数据源为主，多个动态数据源为辅的结构。除了数据库，后续会结合shiro安全框架来搭建。
2、引用
在pom.xml添加框架Springboot +FastMybatis + Druid相关maven引用。
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>net.oschina.durcframework</groupId>
<artifactId>fastmybatis-spring-boot-starter</artifactId>
<version>${fastmybatis.version}</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid-spring-boot-starter</artifactId>
<version>${druid.version}</version>
</dependency>
<dependency>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-core</artifactId>
<version>${shiro.version}</version>
</dependency>
<dependency>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-spring</artifactId>
<version>${shiro.version}</version>
</dependency>
3、数据源队列
我们采用的是一个数据源为主，多个动态数据源为辅的结构，在后续添加新的数据源，我们只要调整新数据源配置就可以了，不用再改原来结构。所以我们要有自己的数据源队列来存储动态的数据源。
/**
* 多数据源队列
*
* @author lisk
*/
public class DynamicContextUtils {
private static final ThreadLocal<Deque<String>> CONTEXT = new ThreadLocal() {
@Override
protected Object initialValue() {
return new ArrayDeque();
}
};
/**
* 获得当前线程数据源
*
* @return 数据源名称
*/
public static String peek() {
return CONTEXT.get().peek();
}
/**
* 设置当前线程数据源
*
* @param dataSource 数据源名称
*/
public static void push(String dataSource) {
CONTEXT.get().push(dataSource);
}
/**
* 清空当前线程数据源
*/
public static void poll() {
Deque<String> deque = CONTEXT.get();
deque.poll();
if (deque.isEmpty()) {
CONTEXT.remove();
}
}
}
4、数据源切面
首先我们要添加自己的annotion，并可以切面中可以拦截并加载动态数据源。
@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Inherited
public @interface DataSource {
String value() default "";
}
现在我们在切面中拦截自己添加的annotion，然后通过@Aspect添加到我们定义的数据源队列中。
@Aspect
@Component
@Order(Ordered.HIGHEST_PRECEDENCE)
public class DataSourceAspect {
protected Logger logger = LoggerFactory.getLogger(DataSourceAspect.class);
@Pointcut("@annotation(com.xhl.lk.auth2.datasource.annotation.DataSource)" +
"|| @within(com.xhl.lk.auth2.datasource.annotation.DataSource)")
public void dataSourcePointCut(){
}
@Around("dataSourcePointCut()")
public Object around(@NotNull ProceedingJoinPoint point) throws Throwable{
MethodSignature signature = (MethodSignature) point.getSignature();
Class targetClass = point.getTarget().getClass();
Method method = signature.getMethod();
DataSource targetDataSource = (DataSource) targetClass.getAnnotation(DataSource.class);
DataSource methodDataSource = method.getAnnotation(DataSource.class);
if(Objects.nonNull(targetDataSource) || Objects.nonNull(methodDataSource)){
String value = Objects.nonNull(methodDataSource) ? methodDataSource.value() : targetDataSource.value();
DynamicContextUtils.push(value);
logger.debug("set datasource is {}", value);
}
try{
return point.proceed();
}finally {
DynamicContextUtils.poll();
logger.info("clean datasource");
}
}
}
5、数据源属性
添加Druid主数据源和动态数据源参数映射类，以便可以通过映射来调整和链接数据库。
/**
* 多数据源属性
*
* @author lisk
*/
@Data
public class DataSourceProperty {
private String driverClassName;
private String url;
private String username;
private String password;
/**
* Druid默认参数
*/
private int initialSize = 2;
private int maxActive = 10;
private int minIdle = -1;
private long maxWait = 60 * 1000L;
private long timeBetweenEvictionRunsMillis = 60 * 1000L;
private long minEvictableIdleTimeMillis = 1000L * 60L * 30L;
private long maxEvictableIdleTimeMillis = 1000L * 60L * 60L * 7;
private String validationQuery = "select 1";
private int validationQueryTimeout = -1;
private boolean testOnBorrow = false;
private boolean testOnReturn = false;
private boolean testWhileIdle = true;
private boolean poolPreparedStatements = false;
private int maxOpenPreparedStatements = -1;
private boolean sharePreparedStatements = false;
private String filters = "stat,wall";
}
动态数据源属性以当前主数据源为主，从队列中获取。通过@ConfigurationProperties来标识动态数据源前缀。
@Data
@ConfigurationProperties(prefix = "dynamic")
public class DynamicDataSourceProperty {
private Map<String, DataSourceProperty> datasource = new LinkedHashMap<>();
}
我们在配置文件application.yml定义多个数据源配置：
spring:
datasource:
type: com.alibaba.druid.pool.DruidDataSource
druid:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://192.168.254.128:3306/sys_xhl?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=Asia/Shanghai
username: shdxhl
password: shdxhl
initial-size: 10
max-active: 100
min-idle: 10
max-wait: 60000
pool-prepared-statements: true
max-pool-prepared-statement-per-connection-size: 20
time-between-eviction-runs-millis: 60000
min-evictable-idle-time-millis: 300000
#Oracle需要打开注释
#validation-query: SELECT 1 FROM DUAL
#spring.datasource.druid.test-on-borrow=true
#spring.datasource.druid.test-while-idle=true
test-while-idle: true
test-on-borrow: true
test-on-return: false
stat-view-servlet:
enabled: true
url-pattern: /druid/*
#login-username: admin
#login-password: admin
filter:
stat:
log-slow-sql: true
slow-sql-millis: 1000
merge-sql: false
wall:
config:
multi-statement-allow: true
##多数据源的配置
dynamic:
datasource:
slave1:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://192.168.254.128:3306/blog_weike?useUnicode=true&characterEncoding=UTF-8&useSSL=false&serverTimezone=Asia/Shanghai
username: blog
password: wiloveyou
# slave2:
# driver-class-name: org.postgresql.Driver
# url: jdbc:postgresql://localhost:5432/renren_security
# username: renren
# password: 123456
6、Config初始化
在@Configuration中实现主数据源和多个动态数据源数据链接初始化，同时通过继承AbstractRoutingDataSource来实现动态数据源切换。
//通过重载determineCurrentLookupKey 来获取切换的数据源Key。
public class DynamicDataSource extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
return DynamicContextUtils.peek();
}
}
创建一个Dynamic数据源的Factory来实现动态数据源参数映射和Druid数据源初始化：
public class DynamicDataSourceFactory {
protected static Logger logger = LoggerFactory.getLogger(DynamicDataSourceFactory.class);
//build动态数据源，初始化
public static DruidDataSource buildDruidDataSource(DataSourceProperty properties) {
DruidDataSource druidDataSource = new DruidDataSource();
druidDataSource.setDriverClassName(properties.getDriverClassName());
druidDataSource.setUrl(properties.getUrl());
druidDataSource.setUsername(properties.getUsername());
druidDataSource.setPassword(properties.getPassword());
druidDataSource.setInitialSize(properties.getInitialSize());
druidDataSource.setMaxActive(properties.getMaxActive());
druidDataSource.setMinIdle(properties.getMinIdle());
druidDataSource.setMaxWait(properties.getMaxWait());
druidDataSource.setTimeBetweenEvictionRunsMillis(properties.getTimeBetweenEvictionRunsMillis());
druidDataSource.setMinEvictableIdleTimeMillis(properties.getMinEvictableIdleTimeMillis());
druidDataSource.setMaxEvictableIdleTimeMillis(properties.getMaxEvictableIdleTimeMillis());
druidDataSource.setValidationQuery(properties.getValidationQuery());
druidDataSource.setValidationQueryTimeout(properties.getValidationQueryTimeout());
druidDataSource.setTestOnBorrow(properties.isTestOnBorrow());
druidDataSource.setTestOnReturn(properties.isTestOnReturn());
druidDataSource.setPoolPreparedStatements(properties.isPoolPreparedStatements());
druidDataSource.setMaxOpenPreparedStatements(properties.getMaxOpenPreparedStatements());
druidDataSource.setSharePreparedStatements(properties.isSharePreparedStatements());
try {
druidDataSource.setFilters(properties.getFilters());
druidDataSource.init();
} catch (SQLException e) {
logger.error("DynamicDataSourceFactory is error:" + e.toString());
}
return druidDataSource;
}
}
最后我们在@Configuration添加多个数据源对象bean实例：
@Configuration
@EnableConfigurationProperties(DynamicDataSourceProperty.class)
public class DynamicDataSourceConfig {
@Autowired
private DynamicDataSourceProperty properties;
@Bean
@ConfigurationProperties(prefix = "spring.datasource.druid")
public DataSourceProperty dataSourceProperty() {
return new DataSourceProperty();
}
@Bean
public DynamicDataSource dynamicDataSource(DataSourceProperty dataSourceProperty) {
DynamicDataSource dynamicDataSource = new DynamicDataSource();
dynamicDataSource.setTargetDataSources(getDynamicDataSource());
//默认数据源
DruidDataSource defaultDataSource = DynamicDataSourceFactory.buildDruidDataSource(dataSourceProperty);
dynamicDataSource.setDefaultTargetDataSource(defaultDataSource);
return dynamicDataSource;
}
private Map<Object, Object> getDynamicDataSource(){
Map<String, DataSourceProperty> dataSourcePropertyMap = properties.getDatasource();
Map<Object, Object> targetDataSources = new ConcurrentHashMap<>(dataSourcePropertyMap.size());
dataSourcePropertyMap.forEach((k, v) -> {
DruidDataSource druidDataSource = DynamicDataSourceFactory.buildDruidDataSource(v);
targetDataSources.put(k, druidDataSource);
});
return targetDataSources;
}
}
7、验证
最后我们可以很轻松的验证当前Druid多数据源配置是否生效，通过访问http://localhost:8080/lk-auth/druid/的地址，可以很清楚的看到数据库执行语句和数据源的各种指标。代码链接：https://gitee.com/lhdxhl/lk-auth.git
