Camel+SpringBoot+JPA，多个数据源找不到正确的持久性单元

Question

我有一个spring-boot服务，使用JPA和Apachecamel。我配置了以下两个不同的数据源https://www.baeldung.com/spring-data-jpa-multiple-databases到目前为止，数据源本身似乎已经就位。然而，骆驼并不是根据persistenceUnit的名称来采摘它们的。当我删除所有与其中一个数据源相关的代码时，它就会突然工作起来。在我看来，persistenceUnit的名称设置不正确。我总是得到以下错误：

javax.persistence.PersistenceException: No Persistence provider for EntityManager named domain

我还将我的方法与带有多个数据源的Spring Boot+Camel JPA进行了比较

数据源1:

import org.hibernate.jpa.HibernatePersistenceProvider;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import javax.persistence.PersistenceContext;
import javax.sql.DataSource;
import java.util.HashMap;
@Configuration
@PropertySource({"classpath:database.properties"})
@EnableJpaRepositories(
basePackages = {"com.myapp.persistence.domain"},
entityManagerFactoryRef = "domainEntityManager",
transactionManagerRef = "domainTransactionManager")
public class PersistenceDomainAutoConfiguration {
@Autowired
private Environment env;
@Bean
@Primary
@ConfigurationProperties(prefix = "spring.datasource")
public DataSource domainDataSource() {
return DataSourceBuilder.create().build();
}
@Bean
@Primary
@PersistenceContext(unitName = "domain")
public LocalContainerEntityManagerFactoryBean domainEntityManager() {
final LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
em.setDataSource(domainDataSource());
em.setPackagesToScan("com.myapp.model.domain","com.myapp.legacy");
em.setPersistenceProviderClass(HibernatePersistenceProvider.class);
em.setPersistenceUnitName("domain");
final HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
em.setJpaVendorAdapter(vendorAdapter);
final HashMap<String, Object> properties = new HashMap<String, Object>();
properties.put("hibernate.hbm2ddl.auto", env.getProperty("hibernate.hbm2ddl.auto"));
properties.put("hibernate.dialect",
"org.hibernate.dialect.PostgreSQLDialect");
em.setJpaPropertyMap(properties);
return em;
}

@Bean
public PlatformTransactionManager domainTransactionManager() {
final JpaTransactionManager transactionManager = new JpaTransactionManager();
transactionManager.setEntityManagerFactory(domainEntityManager().getObject());
return transactionManager;
}
}

数据源2:

package com.myapp.configuration;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.env.Environment;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import javax.persistence.PersistenceContext;
import javax.sql.DataSource;
import java.util.HashMap;
@Configuration
@PropertySource({"classpath:database.properties"})
@EnableJpaRepositories(
basePackages = "com.myapp.persistence.lookup",
entityManagerFactoryRef = "lookupEntityManager",
transactionManagerRef = "lookupTransactionManager")
public class PersistenceLookupAutoConfiguration {
@Autowired
private Environment env;
@Bean
@ConfigurationProperties(prefix="spring.currency-datasource")
public DataSource lookupDataSource() {
return DataSourceBuilder.create().build();
}
@Bean
@PersistenceContext(unitName = "lookup")
public LocalContainerEntityManagerFactoryBean lookupEntityManager() {
final LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
em.setDataSource(lookupDataSource());
em.setPackagesToScan("com.myapp.model.lookup");
em.setPersistenceUnitName("lookup");
final HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
em.setJpaVendorAdapter(vendorAdapter);
final HashMap<String, Object> properties = new HashMap<String, Object>();
properties.put("hibernate.hbm2ddl.auto", env.getProperty("hibernate.hbm2ddl.auto"));
properties.put("hibernate.dialect", "org.hibernate.dialect.SQLServerDialect");
em.setJpaPropertyMap(properties);
return em;
}

@Bean
public PlatformTransactionManager lookupTransactionManager() {
final JpaTransactionManager transactionManager = new JpaTransactionManager();
transactionManager.setEntityManagerFactory(lookupEntityManager().getObject());
return transactionManager;
}
}

骆驼路线摘录：

...
.to("jpa:com.myapp.model.domain.Event?entityType=java.util.ArrayList&persistenceUnit=domain")

Answer 1

使用persistenceUnit 的entityManagerFactory选项实例