Question

在我要保存到两个数据源的持续努力中，我试图通过给它们两个自定义前缀添加两个数据源到我的application.properties文件中，就像在官方spring文档中所做的那样：https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#howto-two-datasources。当我这样做并插入数据时，该数据将不会保存到mysql数据库中，最终会出现空数据集和错误（请参见下文）。但是，如果我在数据源上使用原始前缀，而在另一个数据库上使用更改的前缀，则确实会保存，但只能在前缀未更改的数据库中保存。

这是我对用户（db1）的配置：

import com.zaxxer.hikari.HikariDataSource;
import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Primary;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;

public class UserConfiguration {


    @Bean
    @Primary
    @ConfigurationProperties(prefix="spring.datasource.db1")
    public DataSourceProperties firstDataSourceProperties() {
        return new DataSourceProperties();
    }

    @Bean
    @Primary
    @ConfigurationProperties("spring.datasource.db1.configuration")
    public HikariDataSource firstDataSource() {
        return firstDataSourceProperties().initializeDataSourceBuilder()
                .type(HikariDataSource.class).build();

    }

    @Primary
    @Bean
    public LocalContainerEntityManagerFactoryBean userEntityManagerFactory(
            EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(firstDataSource())
                .packages("User.class")//User.class
                .persistenceUnit("users")
                .build();
    }
}

产品（db2）的配置

import org.apache.commons.dbcp.BasicDataSource;
import org.springframework.boot.autoconfigure.jdbc.DataSourceProperties;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;


public class ProductConfiguration {

    @Bean
    @ConfigurationProperties(prefix="spring.datasource.db2")
    public DataSourceProperties secondDataSourceProperties() {
        return new DataSourceProperties();
    }

    @Bean
    @ConfigurationProperties("spring.datasource.db2.configuration")
    public BasicDataSource secondDataSource() {
        return secondDataSourceProperties().initializeDataSourceBuilder()
                .type(BasicDataSource.class).build();
    }

    @Bean
    public LocalContainerEntityManagerFactoryBean productEntityManagerFactory(
            EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(secondDataSource())
                .packages("Product.class")//Product.class
                .persistenceUnit("products")
                .build();
    }
}

application.properties文件不起作用

spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.show-sql=true

logging.level.org.hibernate.SQL=DEBUG
logging.level.org.hibernate.type.descriptor.sql.BasicBinder=TRACE

spring.datasource.db1.url=jdbc:mysql://localhost/db1?autoReconnect=true&useSSL=false
spring.datasource.db1.username=user
spring.datasource.db1.password=pass
spring.datasource.db1.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.db1.configuration.maximum-pool-size=30

spring.datasource.db2.url=jdbc:mysql://localhost/db2?autoReconnect=true&useSSL=false
spring.datasource.db2.username=user
spring.datasource.db2.password=pass
spring.datasource.db2.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.db2.max-total=30

错误

***************************
APPLICATION FAILED TO START
***************************

Description:

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.

Reason: Failed to determine a suitable driver class


Action:

Consider the following:
    If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
    If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

application.properties文件起作用一半。仅保存到db 1的数据。

spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.show-sql=true

logging.level.org.hibernate.SQL=DEBUG
logging.level.org.hibernate.type.descriptor.sql.BasicBinder=TRACE

spring.datasource.url=jdbc:mysql://localhost/db1?autoReconnect=true&useSSL=false
spring.datasource.username=user
spring.datasource.password=pass
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.configuration.maximum-pool-size=30

spring.datasource.db2.url=jdbc:mysql://localhost/db2?autoReconnect=true&useSSL=false
spring.datasource.db2.username=user
spring.datasource.db2.password=pass
spring.datasource.db2.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.db2.max-total=30

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.test.multidb</groupId>
    <artifactId>multipledb</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.3.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>

        <dependency>
            <groupId>commons-dbcp</groupId>
            <artifactId>commons-dbcp</artifactId>
            <version>1.2.2</version>
        </dependency>
    </dependencies>

</project>

因此，这使我相信我的应用程序不接受更改的前缀。我在这里想念什么？我尝试使用不同的Maven依赖版本，不同的驱动程序符号，并尝试添加H2数据库依赖项。但是我在一个错误中绊倒。

Answer 1

确定尝试这样做：

您必须像这样拆分存储库：

src/main/java
- com.foobar   
  - user
    - domain
    - repo
  - products
    - domain
    - repo

在仓库中放置您的@Repository接口，并在域中放置您的实体。

application.properties

spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.show-sql=true

logging.level.org.hibernate.SQL=DEBUG
logging.level.org.hibernate.type.descriptor.sql.BasicBinder=TRACE

spring.datasource.url=jdbc:mysql://localhost/db1?autoReconnect=true&useSSL=false
spring.datasource.username=user
spring.datasource.password=pass
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.configuration.maximum-pool-size=30

db2.datasource.url=jdbc:mysql://localhost/db2?autoReconnect=true&useSSL=false
db2.datasource.username=user
db2.datasource.password=pass
db2.datasource.driver-class-name=com.mysql.jdbc.Driver
db2.datasource.max-total=30

DB1的配置（第一个数据源）

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
  entityManagerFactoryRef = "entityManagerFactory",
  basePackages = { "com.foobar.user.repo" }
)
public class UserConfiguration {

  @Primary
  @Bean(name = "dataSource")
  @ConfigurationProperties(prefix = "spring.datasource")
  public DataSource dataSource() {
    return DataSourceBuilder.create().build();
  }

  @Primary
  @Bean(name = "entityManagerFactory")
  public LocalContainerEntityManagerFactoryBean entityManagerFactory(EntityManagerFactoryBuilder builder, @Qualifier("dataSource") DataSource dataSource) {
    return builder
      .dataSource(dataSource)
      .packages("com.foobar.user.domain")
      .persistenceUnit("userPU")
      .build();
  }

  @Primary
  @Bean(name = "transactionManager")
  public PlatformTransactionManager transactionManager(@Qualifier("entityManagerFactory") EntityManagerFactory entityManagerFactory) {
    return new JpaTransactionManager(entityManagerFactory);
  }
}

DB2的配置（Secondy数据源）

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
  entityManagerFactoryRef = "db2EntityManagerFactory",
  transactionManagerRef = "db2TransactionManager",
  basePackages = { "com.foobar.products.repo" }
)
public class ProductConfiguration {

  @Bean(name = "db2DataSource")
  @ConfigurationProperties(prefix = "db2.datasource")
  public DataSource dataSource() {
    return DataSourceBuilder.create().build();
  }

  @Bean(name = "db2EntityManagerFactory")
  public LocalContainerEntityManagerFactoryBean 
  db2EntityManagerFactory(EntityManagerFactoryBuilder builder, @Qualifier("barDataSource") DataSource dataSource) {
    return
      builder
        .dataSource(dataSource)
        .packages("com.foobar.products.domain")
        .persistenceUnit("productPU")
        .build();
  }
  @Bean(name = "db2TransactionManager")
  public PlatformTransactionManager db2TransactionManager(@Qualifier("db2EntityManagerFactory") EntityManagerFactory db2EntityManagerFactory) {
    return new JpaTransactionManager(db2EntityManagerFactory);
  }
}

希望这会有所帮助！

application.properties数据源问题

1 个答案: