Testcontainers PostgreSQLContainer Sınıfı

Giriş

Şu satırı dahil ederiz

import org.testcontainers.containers.PostgreSQLContainer;

Üç tane bağımlılık gerekiyor. Açıklaması şöyle

1. org.testcontainers:testcontainers

includes core packages.

2. org.testcontainers:postgresql

includes PostgreSQL-specific packages. This dependency depends on database which your application is using. You will find the list of supported databases here.

3. org.testcontainers:junit-jupiter

integrates JUnit with Testcontainers.

Maven

Şu satırı dahil ederiz

<properties>
  <testcontainers.version>1.16.0</testcontainers.version>
</properties>

<dependency>
  <groupId>org.testcontainers</groupId>
  <artifactId>junit-jupiter</artifactId>
  <scope>test</scope>
</dependency>

<dependency>
  <groupId>org.testcontainers</groupId>
  <artifactId>postgresql</artifactId>
  <scope>test</scope>
</dependency>

<dependencyManagement>
  <dependencies>
    <dependency>
      <groupId>org.testcontainers</groupId>
      <artifactId>testcontainers-bom</artifactId>
      <version>${testcontainers.version}</version>
      <type>pom</type>
      <scope>import</scope>
    </dependency>
  </dependencies>
</dependencyManagement>

Gradle

Şöyle yaparız

dependencies {
 ...
 testImplementation 'org.testcontainers:testcontainers'
 testImplementation 'org.testcontainers:postgresql' 
 testImplementation 'org.testcontainers:junit-jupiter'
 ...
}

dependencyManagement {
 imports {
  mavenBom "org.testcontainers:testcontainers-bom:1.17.6"
 }
}

1. DriverManager.getConnection İle Kullanımı

PostgreSQLContainer nesnesi yaratıldıktan sonra JDBC ile iş yapacaksak DriverManager nesnesini kullanarak JDBC Connection elde etmek lazım. 

Örnek - URL + UserName + Password

DriverManager.getConnection() çağrısına kullanıcı adı ve şifre geçeceksek şöyle yaparız

DockerImageName POSTGRES_IMAGE =
  DockerImageName.parse("debezium/example-postgres:1.7")
  .asCompatibleSubstituteFor("postgres");

PostgreSQLContainer container = new PostgreSQLContainer<>(POSTGRES_IMAGE)
  .withDatabaseName("postgres")
  .withUsername("postgres")
  .withPassword("postgres")
  .withConnectTimeoutSeconds(300)
  .withStartupTimeoutSeconds(300)
  .withStartupAttempts(5)
  .withCreateContainerCmdModifier(createContainerCmd -> {...})

container.start();

 try (Connection connection = DriverManager.getConnection(container.getJdbcUrl(), 
                                                          container.getUsername(),
                                                          container.getPassword())) {
  connection.setSchema("inventory");
  try (Statement statement = connection.createStatement()) {
    ...
  }
}

Örnek - URL İçinde UserName ve Password

Eğer DriverManager.getConnection() ile sadece URL kullanacaksak şöyle yapmak gerekiyor

String jdbcUrl = container.getJdbcUrl() + "&user=" + container.getUsername() +
                                  "&password=" + container.getPassword();
// Output
jdbc:postgresql://localhost:52135/test?loggerLevel=OFF&user=test&password=test

 2. PostgreSQLContainer Metodlar

Çok fazla metod var. Bazı örnekler aşağıda

getDriverClassName metodu

Örnek - Eski Spring Kodu

Şöyle yaparız.  Yeni Spring ile artık @DynamicPropertySource anotasyonuna gerek yok

@Testcontainers
@ContextConfiguration(classes = {PersistenceConfig.class})
@DataJpaTest
@AutoConfigureTestDatabase(replace = AutoConfigureTestDatabase.Replace.NONE)
public class StudentRepositoryJpaIT extends StudentRepositoryTest {

  @Container
  public static PostgreSQLContainer container = new PostgreSQLContainer("postgres:latest")
    .withDatabaseName("students_db")
    .withUsername("sa")
    .withPassword("sa");


  @DynamicPropertySource
  public static void overrideProperties(DynamicPropertyRegistry registry){
    registry.add("spring.datasource.url", container::getJdbcUrl);
    registry.add("spring.datasource.username", container::getUsername);
    registry.add("spring.datasource.password", container::getPassword);
    registry.add("spring.datasource.driver-class-name", container::getDriverClassName);
  }
  ...
}

getFirstMappedPort

Örnek

Şöyle yaparız

Integer hostPort = container.getFirstMappedPort();

getHost metodu

Örnek

Şöyle yaparız

String host = container.getHost()

getJdbcUrl metodu

Şöyle yaparız

import org.junit.jupiter.api.Test;
import org.testcontainers.containers.PostgreSQLContainer;

public class PostgresIntegrationTest {
  @Container
  private static final PostgreSQLContainer<?> postgresContainer =
    new PostgreSQLContainer<>("postgres:latest");

  @Test
  void testDatabaseConnection() {
    // Get database connection properties from the container instance
    String jdbcUrl = postgresContainer.getJdbcUrl();
    String username = postgresContainer.getUsername();
    String password = postgresContainer.getPassword();

    // Perform database tests using the connection properties
    // ...
  }
}

getMappedPort metodu

Açıklaması şöyle

You cannot choose which actual port is used on the host machine. TestContainers chooses one automatically and makes it accessible through getMappedPort(containerPort) method on the container instance. You can also use getFirstMappedPort() if you only have one.

Örnek

Şöyle yaparız

Integer hostPort = container.getMappedPort(8080);

Örnek

Şöyle yaparız. PostgreSQLContainer.POSTGRESQL_PORT değişkenin değeri 5432

Integer hostPort = container.getMappedPort(PostgreSQLContainer.POSTGRESQL_PORT);

withCommand metodu

Örnek

Şöyle yaparız

public static PostgreSQLContainer container = new PostgreSQLContainer<>("postgres:12.1")
  .withCommand("postgres -c max_prepared_transactions=10")
  .withCommand("postgres -c max_connections=500");

Aynı şeyi şöyle yaparız

public static PostgreSQLContainer container = new PostgreSQLContainer<>("postgres:12.1")
  .withCommand("postgres -c max_prepared_transactions=10 -c max_connections=500");

withTmpFs metodu

Örnek

Şöyle yaparız. Burada PGDATA ortam değişkeni de /var/lib/postgresql/data olarak değiştiriliyor ama bence gerek yok. Çünkü varsayılan değer zaten böyle

var container = PostgreSQLContainer(postgresDockerImage)
  .withDatabaseName("dataBaseName")
  .withUsername("username")
  .withPassword("password")
  .withEnv(mapOf("PGDATA" to "/var/lib/postgresql/data"))
  .withTmpFs(mapOf("/var/lib/postgresql/data" to "rw"))

withUsername metodu

Şöyle yaparız

@Container
private static final PostgreSQLContainer<?> postgresContainer =
  new PostgreSQLContainer<>(DockerImageName.parse("postgres:latest"))
    .withDatabaseName("mydb")
    .withUsername("user")
    .withPassword("password");