Spring初始化多个数据库

Posted 2023-02-26

【中文标题】Spring初始化多个数据库

【英文标题】：Initialize multiple databases in Spring

【发布时间】：2018-04-18 17:09:15

【问题描述】：

我正在使用 AbstractRoutingDatasource 在运行时在数据库之间进行路由。在informix 数据库的实际情况下，一切正常。

对于测试，我创建了一个弹簧配置文件以在内存 H2 数据库中使用。 在使用测试配置文件运行 spring 应用程序后，我使用 h2 控制台检查了本地数据库。未创建架构。

我尝试在资源和休眠中使用 schema.sql：

generate-ddl: true
hibernate:
  ddl-auto: create-drop

休眠抛出

java.lang.IllegalStateException: Cannot determine target DataSource for lookup key [null]

据我了解，hibernate 试图仅生成“路由”数据源。由于没有设置 DatabaseContextHolder (null)，因此失败。

所以两种方式都失败了。

有没有办法用（相同的）架构初始化所有数据库？

我在下面列出了我的配置。

bootstrap.yml：

spring:
  profiles: acceptanceTest
  config:
    name: standalone
  cloud:
    config:
      enabled: false
      discovery:
        enabled: false
  jpa:
    database-platform: org.hibernate.dialect.H2Dialect
    generate-ddl: true
    hibernate:
      ddl-auto: create-drop
    properties:
      hibernate:
        show_sql: false
        use_sql_comments: false
        format_sql: false
  h2:
    console:
      enabled: true
      path: /h2
datasource:
  mc:
    driver-class-name: 'org.h2.Driver'
    url: 'jdbc:h2:mem:test-mc-db;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE'
    username: sa
    password: ''
    platform: h2
    initialize: true
    type: com.zaxxer.hikari.HikariDataSource
    hikari:
      maximum-pool-size: 10
      minimum-idle: 0
      idle-timeout: 60000
      pool-name: MarkHikariPool
  cw:
    driver-class-name: 'org.h2.Driver'
    url: 'jdbc:h2:mem:test-cw-db'
    username: sa
    password: ''
    type: com.zaxxer.hikari.HikariDataSource
    hikari:
      maximum-pool-size: 10
      minimum-idle: 0
      idle-timeout: 60000
      pool-name: MarkHikariPool

MainApp.java：

@ComponentScan( "de.md.mark" )
@EnableDiscoveryClient
@SpringBootApplication(
    exclude =
        
            DataSourceAutoConfiguration.class,
            DataSourceTransactionManagerAutoConfiguration.class,
            HibernateJpaAutoConfiguration.class
        
)
public class MainApp

    public static void main(String[] args)
    

DataSourceConfiguration.java：

@Configuration
@EnableJpaRepositories(
    basePackageClasses =  MarkTypeRepository.class, MarkRepository.class , entityManagerFactoryRef = "markEntityManager",
    transactionManagerRef = "markTransactionManager"
)
@EnableTransactionManagement
public class DataSourceConfiguration

    @Autowired(required = false)
    private PersistenceUnitManager persistenceUnitManager;

    @Bean
    @ConfigurationProperties("app.jpa")
    @Primary
    public JpaProperties jpaProperties()
    
        return new JpaProperties();
    

    @Bean
    @ConfigurationProperties(prefix = "datasource.mc")
    public DataSource mcDataSource()
    
        return DataSourceBuilder.create().build();
    

    @Bean
    @ConfigurationProperties(prefix = "datasource.cw")
    public DataSource cwDataSource()
    
        return DataSourceBuilder.create().build();
    

    @Bean
    @Primary
    public DataSource dataSource()
    
        DataSourceRouter router = new DataSourceRouter();

        final HashMap<Object, Object> map = new HashMap<>(DatabaseEnvironment.values().length);
        map.put(DatabaseEnvironment.MC, mcDataSource());
        map.put(DatabaseEnvironment.CW, cwDataSource());
        router.setTargetDataSources(map);
        return router;
    

    @Bean
    @Primary
    public LocalContainerEntityManagerFactoryBean markEntityManager(final JpaProperties jpaProperties)
    
        EntityManagerFactoryBuilder builder = createEntityManagerFactoryBuilder(jpaProperties);

        return builder.dataSource(dataSource()).packages(MarkTypeEntity.class).persistenceUnit("markEntityManager").build();
    

    @Bean
    @Primary
    public JpaTransactionManager markTransactionManager(@Qualifier("markEntityManager") final EntityManagerFactory factory)
    
        return new JpaTransactionManager(factory);
    

    private EntityManagerFactoryBuilder createEntityManagerFactoryBuilder(JpaProperties jpaProperties)
    
        JpaVendorAdapter jpaVendorAdapter = createJpaVendorAdapter(jpaProperties);
        return new EntityManagerFactoryBuilder(jpaVendorAdapter, jpaProperties.getProperties(), this.persistenceUnitManager);
    

    private JpaVendorAdapter createJpaVendorAdapter(JpaProperties jpaProperties)
    
        AbstractJpaVendorAdapter adapter = new HibernateJpaVendorAdapter();
        adapter.setShowSql(jpaProperties.isShowSql());
        adapter.setDatabase(jpaProperties.getDatabase());
        adapter.setDatabasePlatform(jpaProperties.getDatabasePlatform());
        adapter.setGenerateDdl(jpaProperties.isGenerateDdl());
        return adapter;
    

【参考方案1】：

经过这两天的大量研究，我找到了一个初始化所有数据源的解决方案。 我创建了一个使用hibernate的SchemaExport.class创建和初始化本地H2数据库的方法。 由于我只需要本地数据库进行测试，因此我在 @Before 黄瓜方法中调用每个 DatabaseEnvirement 的方法。

public void createDatabase(DatabaseEnvironment environment)
throws Exception

    // load hibernate configuration from hibernate.cfg.xml in classpath
    Configuration configuration = new Configuration().configure();
    MetadataSources metadata =
    new MetadataSources(new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build());

    ClassPathScanningCandidateComponentProvider scanner = new ClassPathScanningCandidateComponentProvider(true);
    scanner.addIncludeFilter(new AnnotationTypeFilter(Entity.class));

    for (BeanDefinition def : scanner.findCandidateComponents(MarkEntity.class.getPackage().getName()))
    
        metadata.addAnnotatedClass(Class.forName(def.getBeanClassName()));
    

    Connection connection = DriverManager.getConnection("jdbc:h2:mem:test-" + environment.name().toLowerCase(), "sa", "");

    SchemaExport export = new SchemaExport((MetadataImplementor) metadata.buildMetadata(), connection);
    export.create(true, true);



@Before
public void beforeTest()
    throws Exception

    // initialise databases
    for (DatabaseEnvironment env : DatabaseEnvironment.values())
    
        createDatabase(env);
    

这就是我的 hibernate.cfg.xml 的样子：

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>

        <property name="dialect">org.hibernate.dialect.H2Dialect</property>

        <property name="show_sql">true</property>

        <property name="hbm2ddl.auto">create-drop</property>

    </session-factory>
</hibernate-configuration>