sample testconfiguration for spring

initial.sql

-- script to create things that are supposed to be there even _before_ liquibase kicks in
create schema myapp;

TCApplicationTests.kt

package sample.example

import org.hamcrest.CoreMatchers
import org.hamcrest.MatcherAssert
import org.junit.jupiter.api.Assertions
import org.junit.jupiter.api.Test
import org.springframework.beans.factory.annotation.Autowired
import org.springframework.boot.test.context.SpringBootTest
import org.springframework.context.annotation.Import
import org.springframework.data.domain.PageRequest
import org.springframework.test.context.ActiveProfiles

import sample.example.config.TCConfiguration
import sample.example.config.JPAConfig
import sample.example.config.JDBCConfig

@SpringBootTest
@ActiveProfiles("test")
@Import(value = [TCConfiguration::class, JPAConfig::class, JDBCConfig::class])
class TCApplicationTests {
  
    @Test
    fun contextLoads() {
    }
    
    // other data-related tests
}

TCConfiguration.kt

package sample.example.config

import org.springframework.boot.test.context.TestConfiguration
import org.springframework.boot.testcontainers.service.connection.ServiceConnection
import org.springframework.context.annotation.Bean
import org.testcontainers.containers.PostgreSQLContainer
import org.testcontainers.utility.DockerImageName

@TestConfiguration(proxyBeanMethods = false)
class TCConfiguration {

	@Bean
	@ServiceConnection
	fun postgresContainer(): PostgreSQLContainer<*> {
		return PostgreSQLContainer(
			DockerImageName
				.parse("postgres:13-alpine")
		)
			.withEnv(
				mapOf(
					"POSTGRES_DB" to "mydatabase",
					"POSTGRES_USER" to "postgres",
					"POSTGRES_PASSWORD" to "postgres"
				)
			)
			.withInitScript("initial.sql")
	}

}