Using TransactionalReadOnly annotation to change data source in runtime for Spring

DatabaseConfiguration.java

@Configuration
@EnableTransactionManagement
public class DatabaseConfiguration {

    @Bean
    @Primary
    @Profile("!test")
    @DependsOn({"primaryDataSource", "replicaDataSource"})
    public DataSource dataSource(@Qualifier("primaryDataSource") HikariDataSource primaryDataSource,
                                 @Qualifier("replicaDataSource") HikariDataSource replicaDataSource) {
        final RoutingDataSource routingDataSource = new RoutingDataSource();

        final Map<Object, Object> targetDataSources = new HashMap<>();
        targetDataSources.put(RoutingDataSource.Route.PRIMARY, primaryDataSource);
        targetDataSources.put(RoutingDataSource.Route.REPLICA, replicaDataSource);

        routingDataSource.setTargetDataSources(targetDataSources);
        routingDataSource.setDefaultTargetDataSource(primaryDataSource);

        return routingDataSource;
    }
    
    @Profile("!test")
    @Bean(destroyMethod = "close")
    public HikariDataSource primaryDataSource() {
        HikariConfig hikariConfig = buildHikariConfig("primary-hikari-pool", dataSourceProperties.getUrl());
        return new HikariDataSource(hikariConfig);
    }

    @Profile("!test")
    @Bean(destroyMethod = "close")
    public HikariDataSource replicaDataSource() {
        HikariConfig hikariConfig = buildHikariConfig("replica-hikari-pool", dataSourceProperties.getReplicaUrl());
        return new HikariDataSource(hikariConfig);
    }
    
    private HikariConfig buildHikariConfig(String poolName, String url) {
        HikariConfig hikariConfig = new HikariConfig();
        hikariConfig.setPoolName(poolName);
        hikariConfig.setDataSourceClassName(dataSourceProperties.getDriverClassName());
        hikariConfig.addDataSourceProperty("url", url);
        hikariConfig.addDataSourceProperty("user", dataSourceProperties.getUsername());
        hikariConfig.addDataSourceProperty("password", dataSourceProperties.getPassword());
        hikariConfig.setMaximumPoolSize(dataSourceProperties.getMaxPoolSize());
        hikariConfig.setMinimumIdle(dataSourceProperties.getMinIdle());
        hikariConfig.setLeakDetectionThreshold(dataSourceProperties.getLeakThreshold());
        hikariConfig.setConnectionTimeout(10000);
        hikariConfig.setMaxLifetime(360000);
        hikariConfig.setIdleTimeout(80000);
        return hikariConfig;
    }

}

ReadOnlyRouteInterceptor.java

@Aspect
@Component
@Order(Ordered.HIGHEST_PRECEDENCE)
@ConditionalOnProperty("read.replica.enabled")
public class ReadOnlyRouteInterceptor {

    @Around("@annotation(TransactionalReadOnly)")
    public Object proceed(ProceedingJoinPoint proceedingJoinPoint) throws Throwable {
        try {
            RoutingDataSource.setReplicaRoute();
            return proceedingJoinPoint.proceed();
        } finally {
            RoutingDataSource.clearReplicaRoute();
        }
    }

}

RoutingDataSource.java

public class RoutingDataSource extends AbstractRoutingDataSource {
    
    private static final ThreadLocal<Route> ctx = new ThreadLocal<>();

    public static void clearReplicaRoute() {
        ctx.remove();
    }

    public static void setReplicaRoute() {
        ctx.set(Route.REPLICA);
    }

    @Override
    protected Object determineCurrentLookupKey() {
        return ctx.get();
    }

    public enum Route {
        PRIMARY, REPLICA
    }
}

TransactionalReadOnly.java

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Transactional(readOnly = true, propagation = Propagation.REQUIRES_NEW)
public @interface TransactionalReadOnly {
  
}