Using a new PostgreSQLContainer test container for each class in a test suite

Question

I am new to integration testing and I am trying to run a suite of tests in a spring boot project using PostgreSQLContainers from the Testcontainers library.

The structure of the suite looks like this:

• Suite
  • @SpringBootTest First Class
    • @Test method
    • @Test method
    • etc.
  • @SpringBootTest Second Class
    • @Test method
    • @Test method
    • etc.

I want to be able to spin up a new, empty container for each class, fill it with a .sql script, run some tests and tear down the container. The issue I am experiencing is that when I try to make the container for the second class the data from the first class is still in the container and I get sql errors because it's trying to re use primary keys.

I am able to run each class individually and the containers work as expected because they are isolated. As soon as I try to run them together in the suite the data seems like it is persisting between the containers.

The general structure of each class is like this:

@ExtendWith(SpringExtension.class)
@SpringBootTest
@AutoConfigureTestDatabase
@TestInstance(TestInstance.Lifecycle.PER_CLASS)
@Testcontainers
public class TestClass1 {
    @Container
    private static PostgreSQLContainer postgresqlContainer = new PostgreSQLContainer()
            .withDatabaseName("foo")
            .withUsername("foo")
            .withPassword("secret");

    @Test
    @Sql("classpath:sql/script.sql")
    void testMethod1() {
        ...
    }    
    
    @Test
    void testMethod2() {
        ...
    }
}

Like I said, I am new to Testcontainers so I am wondering if I am using it wrong or if it is suited to doing these types of suites.