Spring Database Connection 분리

application.yml

spring:
    datasource:
        hikari:
            master:
                jdbc-url: jdbc:mysql://localhost:3306/database?useUnicode=true&characterEncoding=utf8&useSSL=false&useLegacyDatetimeCode=false&serverTimezone=UTC
                username: root
                password: root
                poolName: Hikari
                maximum-pool-size: 2
                auto-commit: false
                data-source-properties:
                    cachePrepStmts: true
                    prepStmtCacheSize: 250
                    prepStmtCacheSqlLimit: 2048
                    useServerPrepStmts: true
            slave:
                jdbc-url: jdbc:mysql://localhost:3306/database?useUnicode=true&characterEncoding=utf8&useSSL=false&useLegacyDatetimeCode=false&serverTimezone=UTC
                username: root
                password: root
                poolName: Hikari
                maximum-pool-size: 2
                auto-commit: false
                data-source-properties:
                    cachePrepStmts: true
                    prepStmtCacheSize: 250
                    prepStmtCacheSqlLimit: 2048
                    useServerPrepStmts: true

DatabaseConfiguration.java

@Configuration
@EnableJpaRepositories("package.to.repository")
@EnableJpaAuditing(auditorAwareRef = "springSecurityAuditorAware")
@EnableTransactionManagement
public class DatabaseConfiguration {

    private final Logger log = LoggerFactory.getLogger(DatabaseConfiguration.class);

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.hikari.master")
    public DataSource masterDataSource() {
        System.out.println("masterDataSource");
        return DataSourceBuilder.create().type(HikariDataSource.class).build();
    }

    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.hikari.slave")
    public DataSource slaveDataSource() {
        return DataSourceBuilder.create().type(HikariDataSource.class).build();
    }

    @Primary
    @Bean
    public DataSource dataSource() {
        ReplicationRoutingDataSource routingDataSource = new ReplicationRoutingDataSource();

        Map<Object, Object> dataSourceMap = new LinkedHashMap<>();
        dataSourceMap.put("master", masterDataSource());
        dataSourceMap.put("slave", slaveDataSource());

        routingDataSource.setTargetDataSources(dataSourceMap);
        routingDataSource.setDefaultTargetDataSource(masterDataSource());
        routingDataSource.afterPropertiesSet();

        return new LazyConnectionDataSourceProxy(routingDataSource);
    }
}

ReplicationRoutingDataSource.java

public class ReplicationRoutingDataSource extends AbstractRoutingDataSource {

    @Override
    protected Object determineCurrentLookupKey() {
        return TransactionSynchronizationManager
            .isCurrentTransactionReadOnly() ? "slave" : "master";
    }
}

https://vladmihalcea.com/read-write-read-only-transaction-routing-spring/