How to re-create database before each test in Spring?

Question

My Spring-Boot-Mvc-Web application has the following database configuration in application.properties file:

spring.datasource.url=jdbc:h2:tcp://         


        

Answer 1

You can annotate your test class with @Transactional:

import org.springframework.transaction.annotation.Transactional;
...

...
@RunWith(SpringRunner.class)
@Transactional
public class MyClassTest {

    @Autowired
    private SomeRepository repository;

    @Before
    public void init() {
       // add some test data, that data would be rolled back, and recreated for each separate test
       repository.save(...);
    }

    @Test
    public void testSomething() {
       // add some more data
       repository.save(...);
       // update some base data
       repository.delete(...);
       // all the changes on database done in that test would be rolled back after test finish
    }
}

All tests are wrapped inside a transaction, that is rolled back at the end of each test. There are unfortunately some problems with that annotation of course, and you need to pay special attention, when for example your production code uses transactions with different score.