原因：org.springframework.beans.factory.NoSuchBeanDefinitionException：没有名为'entityManagerFactory'的bean可用

Question

我想将Spring Boot配置为使用2个JNDI数据源。我尝试了以下配置：

application.properties

spring.production.datasource.jndi-name=java:/global/production_gateway
spring.production.datasource.driver-class-name=org.mariadb.jdbc.Driver
spring.production.datasource.jpa.properties.hibernate.dialect=org.hibernate.dialect.MariaDBDialect
spring.production.datasource.jpa.show-sql = true
spring.production.datasource.jpa.hibernate.ddl-auto = update

spring.warehouse.datasource.jndi-name=java:/global/production_warehouse
spring.warehouse.datasource.driver-class-name=org.mariadb.jdbc.Driver
spring.warehouse.datasource.jpa.properties.hibernate.dialect=org.hibernate.dialect.MariaDBDialect
spring.warehouse.datasource.jpa.show-sql = true
spring.warehouse.datasource.jpa.hibernate.ddl-auto = update

主数据库

    @Configuration
@EnableJpaRepositories(
        basePackages = "org.datalis.plugin.production.entity", 
        entityManagerFactoryRef = "productionEntityManagerFactory", 
        transactionManagerRef = "productionTransactionManager"
    )
@EnableTransactionManagement
public class ContextProductionDatasource {

    @Primary
    @Bean(name = "productionDataSourceProperties")
    @ConfigurationProperties(prefix="spring.production.datasource")
    public JndiPropertyHolder productionDataSourceProperties() {
        return new JndiPropertyHolder();
    }

    @Primary
    @Bean(name = "productionDataSource")
    @ConfigurationProperties(prefix="spring.production.datasource")
    public DataSource productionDataSource() {        
        JndiDataSourceLookup dataSourceLookup = new JndiDataSourceLookup();
        DataSource dataSource = dataSourceLookup.getDataSource(productionDataSourceProperties().getJndiName());
        return dataSource;
    }

    @Primary
    @Bean(name = "productionEntityManager") 
    public EntityManager productionEntityManager(EntityManagerFactory emf) {
        return emf.createEntityManager();
    }

    @Primary
    @Bean(name = "productionEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean productionEntityManagerFactory(
            EntityManagerFactoryBuilder builder) {
        Map<String, Object> properties = new HashMap<String, Object>();
        properties.put("hibernate.hbm2ddl.auto", "update");
        return builder
                .dataSource(productionDataSource())
                .packages("org.datalis.plugin.production.entity")
                .persistenceUnit("production")
                .properties(properties)
                .build();
    }

    @Primary
    @Bean(name = "productionTransactionManager")    
    public PlatformTransactionManager productionTransactionManager(final EntityManagerFactory emf) {
        final JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(emf);
        return transactionManager;
    }

    @Primary
    @Bean(name = "productionExceptionTranslation")
    public PersistenceExceptionTranslationPostProcessor productionExceptionTranslation() {
        return new PersistenceExceptionTranslationPostProcessor();
    }

    private static class JndiPropertyHolder {
        private String jndiName;

        public String getJndiName() {
            return jndiName;
        }

        public void setJndiName(String jndiName) {
            this.jndiName = jndiName;
        }
    }
}

第二个数据源：

    @Configuration
@EnableJpaRepositories(
        basePackages = "org.datalis.plugin.warehouse.entity", 
        entityManagerFactoryRef = "warehouseEntityManagerFactory", 
        transactionManagerRef = "warehouseTransactionManager"
    )
@EnableTransactionManagement
public class ContextWarehouseDatasource {

    @Bean(name = "warehouseDataSourceProperties")
    @ConfigurationProperties(prefix="spring.warehouse.datasource")
    public JndiPropertyHolder warehouseDataSourceProperties() {
        return new JndiPropertyHolder();
    }

    @Bean(name = "warehouseDataSource")
    @ConfigurationProperties(prefix="spring.warehouse.datasource")
    public DataSource warehouseDataSource() {
        JndiDataSourceLookup dataSourceLookup = new JndiDataSourceLookup();
        DataSource dataSource = dataSourceLookup.getDataSource(warehouseDataSourceProperties().getJndiName());
        return dataSource;
    }

    @Bean(name = "warehouseEntityManager")  
    public EntityManager warehouseEntityManager(EntityManagerFactory emf) {
        return emf.createEntityManager();
    }

    @Bean(name = "warehouseEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean warehouseEntityManagerFactory(
            EntityManagerFactoryBuilder builder) {
        Map<String, Object> properties = new HashMap<String, Object>();
        properties.put("hibernate.hbm2ddl.auto", "update");
        return builder
                .dataSource(warehouseDataSource())
                .packages("org.datalis.plugin.warehouse.entity")
                .persistenceUnit("warehouse")
                .properties(properties)
                .build();
    }

    @Bean(name = "warehouseTransactionManager")
    public PlatformTransactionManager warehouseTransactionManager(final EntityManagerFactory emf) {
        final JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(emf);
        return transactionManager;
    }

    @Bean(name = "warehouseExceptionTranslation")
    public PersistenceExceptionTranslationPostProcessor warehouseExceptionTranslation() {
        return new PersistenceExceptionTranslationPostProcessor();
    }

    private static class JndiPropertyHolder {
        private String jndiName;

        public String getJndiName() {
            return jndiName;
        }

        public void setJndiName(String jndiName) {
            this.jndiName = jndiName;
        }
    }
}

部署代码时出现异常：

    Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'entityManagerFactory' available

完整的错误堆栈：https：
//pastebin.com/bBZPZGfu

你知道我该怎么解决吗？

当我删除时：

@Primary
    @Bean(name = "productionEntityManagerFactory")
    public LocalContainerEntityManagerFactoryBean productionEntityManagerFactory(
            EntityManagerFactoryBuilder builder) {
        Map<String, Object> properties = new HashMap<String, Object>();
        properties.put("hibernate.hbm2ddl.auto", "update");
        return builder
                .dataSource(productionDataSource())
                .packages("org.datalis.plugin.production.entity")
                .persistenceUnit("production")
                .properties(properties)
                .build();
    }

该软件包已正确部署。知道为什么吗？

Answer 1

主要问题是要有2个不同的实体管理器，它们可以访问不同的数据库。

因此，产生异常的原因是：Spring Data JPA尝试创建一组存储库，但不知道要使用哪个实体管理器工厂。默认情况下，Spring Data
JPA期望只使用一个实体管理器工厂bean（最好命名为）entityManagerFactory，但是您没有这样的名字。

因此，您必须非常精确地进行配置：例如，您可以将代码组织为2个软件包：...warehouse.*和app.production.*，然后可以指定Spring
Data JPA：@EnableJpaRepositories(basePackages = "...warehouse.**", entityManagerFactoryRef = "warehouseEntityManagerFactory")
和供生产使用的精确配置@EnableJpaRepositories(basePackages = "...production.**", entityManagerFactoryRef = "productionEntityManagerFactory")。

第二步是确保不执行默认的Data
JPA实例化：添加配置属性spring.data.jpa.repositories.enabled=false将解决此问题。

并通过配置查看禁用任何其他类型@EnableJpaRepositories或@EntityScan以上定义的 精确配置 。

并且在创建过程中LocalContainerEntityManagerFactoryBean不要使用注入EntityManagerFactoryBuilder：死简单new LocalContainerEntityManagerFactoryBean()将更好地工作。

最后但并非最不重要的一点是，它通常与应用程序有关：您必须考虑两阶段提交事务：您有2个数据源，可以在单个事务中访问这些数据源，但是每个数据源都由不同的事务管理器管理。