Add tenant dynamically in multitenant database application using Spring MVC and Hibernate

Question

i am developing web application which uses multitenant database configuration.

I want to add tenant dynamically.

I added master controller to create master schem

Answer 1

Replace your MultitenantConnectionProviderImpl.java with this code. Use inject service for creating your tables using configuration class.

@SuppressWarnings("serial")
@Component
@PropertySource("classpath:application.properties")
public class MultiTenantConnectionProviderImpl extends AbstractDataSourceBasedMultiTenantConnectionProviderImpl implements ApplicationListener,ServiceRegistryAwareService {

   @Autowired
   private Environment springEnvironment;

   @Autowired
   private TenantDao tenantDao;

   @Autowired
   @Qualifier("dataSource1")
   DataSource masterDataSource;

   @Autowired
   MultiTenantConnectionProvider connectionProvider;

   @Autowired
   CurrentTenantIdentifierResolver tenantResolver;

   @Autowired
   TenantDatabaseConfig tenantDatabaseConfig;


   private final Map map = new HashMap<>();

   @Override
   public void onApplicationEvent(ContextRefreshedEvent contextRefreshedEvent) {
      init();
   }

   private void init() {
      List tenants = tenantDao.findAll();
      for (Tenant tenant : tenants) {
         map.put(tenant.getTenantKey(), constructDataSource(tenant.getTenantKey()));
      }
   }

   private DataSource constructDataSource(String dbName) {
      DriverManagerDataSource dataSource = new DriverManagerDataSource();
      dataSource.setDriverClassName(springEnvironment.getProperty("tenant.datasource.classname"));
      dataSource.setUrl(springEnvironment.getProperty("tenant.datasource.url") + dbName+"?createDatabaseIfNotExist=true");
      dataSource.setUsername(springEnvironment.getProperty("tenant.datasource.user"));
      dataSource.setPassword(springEnvironment.getProperty("tenant.datasource.password"));

      entityManagerFactory(dataSource,connectionProvider, tenantResolver);


      return dataSource;
   }

   public LocalContainerEntityManagerFactoryBean entityManagerFactory(DataSource dataSource,
           MultiTenantConnectionProvider connectionProvider,
           CurrentTenantIdentifierResolver tenantResolver) {
      LocalContainerEntityManagerFactoryBean emfBean = new LocalContainerEntityManagerFactoryBean();
      emfBean.setDataSource(dataSource);
      emfBean.setPackagesToScan("com.appointment.schedular.model.tenant");
      emfBean.setJpaVendorAdapter(new HibernateJpaVendorAdapter());
      emfBean.setPersistenceProviderClass(HibernatePersistenceProvider.class);
      Map properties = new HashMap<>();
      properties.put(org.hibernate.cfg.Environment.MULTI_TENANT, MultiTenancyStrategy.DATABASE);
      properties.put(org.hibernate.cfg.Environment.MULTI_TENANT_CONNECTION_PROVIDER, connectionProvider);
      properties.put(org.hibernate.cfg.Environment.MULTI_TENANT_IDENTIFIER_RESOLVER, tenantResolver);
      properties.put("hibernate.ejb.naming_strategy", "org.hibernate.cfg.ImprovedNamingStrategy");
        properties.put("hibernate.dialect", springEnvironment.getProperty("hibernate.dialect"
              , "org.hibernate.dialect.MySQLDialect"));
      properties.put("hibernate.show_sql", springEnvironment.getProperty("hibernate.show_sql"
              , "true"));
      properties.put("hibernate.format_sql", springEnvironment.getProperty("hibernate.format_sql"
              , "true"));
      properties.put("hibernate.hbm2ddl.auto", springEnvironment.getProperty("hibernate.hbm2ddl.auto"
              , "update"));
      emfBean.setJpaPropertyMap(properties);
      emfBean.setPersistenceUnitName(dataSource.toString());
      emfBean.afterPropertiesSet();
      //emfBean.setEntityManagerFactoryInterface((EntityMana)emfBean);
      //emfBean.setBeanName("srgsrohtak");
      return emfBean;
   }

   public JpaTransactionManager transactionManager(EntityManagerFactory tenantEntityManager) {
          JpaTransactionManager transactionManager = new JpaTransactionManager();
          transactionManager.setEntityManagerFactory(tenantEntityManager);
          transactionManager.afterPropertiesSet();
          return transactionManager;
   }

   @Override
   public void injectServices(ServiceRegistryImplementor serviceRegistry) {
       Map lSettings = serviceRegistry.getService(ConfigurationService.class).getSettings();
       DataSource localDs =  (DataSource) lSettings.get("hibernate.connection.datasource");
       masterDataSource = localDs;
   }

   @Override
   protected DataSource selectAnyDataSource() {
      return masterDataSource;
   }

   @Override
   protected DataSource selectDataSource(String key) {
      return map.get(key);
   }

   public void addTenant(String tenantKey) {
      map.put(tenantKey, constructDataSource(tenantKey));
   }
}