Spring引导-加载初始数据

我想知道在应用程序启动之前加载初始数据库数据的最佳方法是什么?我要找的是一些东西，将填补我的H2数据库与数据。

例如，我有一个域模型“User”，我可以通过访问/users访问用户，但最初在数据库中不会有任何用户，所以我必须创建它们。有没有办法自动用数据填充数据库?

目前，我有一个Bean，它由容器实例化并为我创建用户。

例子:

@Component
public class DataLoader {

    private UserRepository userRepository;

    @Autowired
    public DataLoader(UserRepository userRepository) {
        this.userRepository = userRepository;
        LoadUsers();
    }

    private void LoadUsers() {
        userRepository.save(new User("lala", "lala", "lala"));
    }
}

但我非常怀疑这是不是最好的办法。真的是这样吗?

当前回答

对于那些使用MysqlDriver的人，我尝试使用@bean注释的Init属性，它是有效的。

在resources\Scripts路径下创建Schema和Data sql文件后

在application.properties中添加该行

spring.jpa.hibernate.ddl-auto=none

编辑应用程序内容:

package com.spring_mvaen.demo;

import org.springframework.boot.CommandLineRunner;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.jdbc.datasource.init.DatabasePopulator;
import org.springframework.jdbc.datasource.init.DatabasePopulatorUtils;
import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator;

@SpringBootApplication
public class DemoApplication implements CommandLineRunner {

  public static void main(String[] args) {
    SpringApplication.run(DemoApplication.class, args);
  }
  @Override
  public void run(String... arg0) throws Exception {
    System.out.println("Hello world from Command Line Runner");
  }

  @Bean(name = "dataSource")
  public DriverManagerDataSource dataSource() {
    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");
    dataSource.setUrl("jdbc:mysql://localhost:3306/db_spring_rest?useUnicode=true&useLegacyDatetimeCode=fa    lse&serverTimezone=UTC&createDatabaseIfNotExist=true&allowPublicKeyRetrieval=true&useSSL=false");
    dataSource.setUsername("root");
    dataSource.setPassword("root");

    // schema init
    Resource initSchema = new ClassPathResource("scripts/schema.sql");
    Resource initData = new ClassPathResource("scripts/data.sql");
    DatabasePopulator databasePopulator = new ResourceDatabasePopulator(initSchema, initData);
    DatabasePopulatorUtils.execute(databasePopulator, dataSource);

    return dataSource;
  }


}

2021-09-13 15:46:05

其他回答

您可以使用下面的代码。在下面的代码中，数据库插入发生在spring引导应用程序启动期间。

@SpringBootApplication
public class Application implements CommandLineRunner {
    
    @Autowired
    private IService<Car> service;

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Override
    public void run(String... args) throws Exception {
        for(int i=1; i<=1000; i++) {
            Car car = new Car();
            car.setName("Car Name "+i);
            book.setPrice(50 + i);
            service.saveOrUpdate(car);
        }
    }

}

2020-06-27 13:35:46

最紧凑的(对于动态数据)将@mathias-dpunkt解决方案放入MainApp(使用Lombok @AllArgsConstructor):

@SpringBootApplication
@AllArgsConstructor
public class RestaurantVotingApplication implements ApplicationRunner {
  private final VoteRepository voteRepository;
  private final UserRepository userRepository;

  public static void main(String[] args) {
    SpringApplication.run(RestaurantVotingApplication.class, args);
  }

  @Override
  public void run(ApplicationArguments args) {
    voteRepository.save(new Vote(userRepository.getOne(1), LocalDate.now(), LocalTime.now()));
  }
}

2018-08-10 13:05:46

对于那些使用MysqlDriver的人，我尝试使用@bean注释的Init属性，它是有效的。

在resources\Scripts路径下创建Schema和Data sql文件后

在application.properties中添加该行

spring.jpa.hibernate.ddl-auto=none

编辑应用程序内容:

package com.spring_mvaen.demo;

import org.springframework.boot.CommandLineRunner;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.jdbc.datasource.DriverManagerDataSource;
import org.springframework.jdbc.datasource.init.DatabasePopulator;
import org.springframework.jdbc.datasource.init.DatabasePopulatorUtils;
import org.springframework.jdbc.datasource.init.ResourceDatabasePopulator;

@SpringBootApplication
public class DemoApplication implements CommandLineRunner {

  public static void main(String[] args) {
    SpringApplication.run(DemoApplication.class, args);
  }
  @Override
  public void run(String... arg0) throws Exception {
    System.out.println("Hello world from Command Line Runner");
  }

  @Bean(name = "dataSource")
  public DriverManagerDataSource dataSource() {
    DriverManagerDataSource dataSource = new DriverManagerDataSource();
    dataSource.setDriverClassName("com.mysql.cj.jdbc.Driver");
    dataSource.setUrl("jdbc:mysql://localhost:3306/db_spring_rest?useUnicode=true&useLegacyDatetimeCode=fa    lse&serverTimezone=UTC&createDatabaseIfNotExist=true&allowPublicKeyRetrieval=true&useSSL=false");
    dataSource.setUsername("root");
    dataSource.setPassword("root");

    // schema init
    Resource initSchema = new ClassPathResource("scripts/schema.sql");
    Resource initData = new ClassPathResource("scripts/data.sql");
    DatabasePopulator databasePopulator = new ResourceDatabasePopulator(initSchema, initData);
    DatabasePopulatorUtils.execute(databasePopulator, dataSource);

    return dataSource;
  }


}

2021-09-13 15:46:05

您可以简单地创建一个导入。在src/main/resources中创建一个sql文件，Hibernate将在创建模式时执行它。

2017-01-13 10:28:59

我创建了一个库，用于在Spring Boot应用程序中加载初始/演示数据。你可以在https://github.com/piotrpolak/spring-boot-data-fixtures上找到它

一旦数据fixture启动器位于类路径上，它将在应用程序启动时自动尝试加载DICTIONARY数据(此行为可以由属性控制)—您所需要做的就是注册一个实现DataFixture的bean。

我发现通过代码加载初始数据优于使用SQL脚本加载:

fixture的逻辑与应用程序逻辑/领域模型非常接近，随着领域的发展，它也会进行重构你可以从增量的演示数据更新中获益——想象一个QA环境中有一些用户数据(在应用程序部署后不需要丢失)，但同时你想为你开发的新功能添加数据

数据夹具示例:

/**
 * You can have as many fixture classes as you want.
 * @Order annotation is respected for the fixtures belonging to the same set.
 * You can make your demo database to be incrementally updated with fresh data
 * each time the application is redeployed - all you need to do is to write
 * a good condition in `canBeLoaded()` method.
 */
@Component
public class InitialDataFixture implements DataFixture {

    private final LanguageRepository languageRepository;

    // ...

    @Override
    public DataFixtureSet getSet() {
      return DataFixtureSet.DICTIONARY;
    }

    /**
     * We want to make sure the fixture is applied once and once only.
     * A more sophisticated condition can be used to create incremental demo data
     * over time without the need to reset the QA database (for example).
     */
    @Override
    public boolean canBeLoaded() {
      return languageRepository.size() == 0;
    }

    /**
     * The actual application of the fixture.
     * Assuming that data fixtures are registered as beans, this method can call
     * other services and/or repositories.
     */
    @Override
    public void load() {
      languageRepository.saveAll(Arrays.asList(
          new Language("en-US"), new Language("pl-PL")));
    }
}

这个概念的灵感来自Symfony Doctrine数据fixture包。

2020-10-14 18:38:06

Spring引导-加载初始数据

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