Spring Boot insert sample data into database upon startup

Question

What is the right way for creating test data upon server startup and inserting them into the database (I\'m using a JPA/JDBC backed Postgres instance).

Preferably in

Answer 1

You can catch ApplicationReadyEvent then insert demo data, for example:

@Component
public class DemoData {

    @Autowired
    private final EntityRepository repo;

    @EventListener
    public void appReady(ApplicationReadyEvent event) {

        repo.save(new Entity(...));
    }
}

Or you can implement CommandLineRunner or ApplicationRunner, to load demo data when an application is fully started:

@Component
public class DemoData implements CommandLineRunner {

    @Autowired
    private final EntityRepository repo;

    @Override
    public void run(String...args) throws Exception {

        repo.save(new Entity(...));
    }
}

@Component
public class DemoData implements ApplicationRunner {

    @Autowired
    private final EntityRepository repo;

    @Override
    public void run(ApplicationArguments args) throws Exception {

        repo.save(new Entity(...));
    }
}

Or even implement them like a Bean right in your Application (or other 'config') class:

@SpringBootApplication
public class Application {

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

    @Bean
    public CommandLineRunner demoData(EntityRepository repo) {
        return args -> { 

            repo.save(new Entity(...));
        }
    }
}