Configure specific in memory database for testing purpose in Spring

How do I configure my Spring Boot application so that when I run unit tests it will use in-memory database such as H2/HSQL but when I run Spring Boot application it will use production database [Postgre/MySQL] ?

Spring profiles can be used for this. This would be a specific way:

Have environment specific properties files:

application.properties:

spring.profiles.active: dev

application-dev.properties

spring.jpa.database: MYSQL
spring.jpa.hibernate.ddl-auto: update

spring.datasource.url: jdbc:mysql://localhost:3306/dbname
spring.datasource.username: username
spring.datasource.password: password

application-test.properties

spring.jpa.database: HSQL

Have both MySQL and H2 drivers in pom.xml, like this:

<dependency>
	<groupId>mysql</groupId>
	<artifactId>mysql-connector-java</artifactId>
	<scope>runtime</scope>
</dependency>

<dependency>
    <groupId>org.hsqldb</groupId>
    <artifactId>hsqldb</artifactId>
    <scope>test</scope>
</dependency>

Last but not the least, annotate Test classes with @ActiveProfiles("test").

Another approach is to add the annotation @AutoConfigureTestDatabase to you test class. My tests usually look like this:

@RunWith(SpringRunner.class)
@DataJpaTest
@AutoConfigureTestDatabase(connection = EmbeddedDatabaseConnection.H2)
public class MyRepositoryTest {

    @Autowired
    MyRepository repository;

    @Test
    public void test() throws Exception {
        // Tests...
    }
}

Note that the embedded database dependency needs to be added in the pom.xml file. For embedded database this annotation is not necessary it will work even if only the dependency is added in pom file.

With @SpringBootTest magic, you just need to do following two changes.

1. Add 'h2' test dependency in pom.xml

> > com.h2database > h2 > test >

2. Use @AutoConfigureTestDatabase

> @RunWith(SpringRunner.class) > @SpringBootTest(classes = MySpringBootApplication.class) > @AutoConfigureTestDatabase > public class SpringBootTest{ > > @Autowired > private RequestRepository requestRepository; > }

Now all the spring jpa bean/repositories used in test will use h2 as backing database.

> 2019-04-26 13:13:34.198 INFO 28627 --- [ main] > beddedDataSourceBeanFactoryPostProcessor : Replacing 'dataSource' > DataSource bean with embedded version > > 2019-04-26 13:13:34.199 INFO 28627 --- [ main] > o.s.b.f.s.DefaultListableBeanFactory : Overriding bean definition > for bean 'dataSource' > > 2019-04-26 13:13:36.194 INFO 28627 --- [ main] > o.s.j.d.e.EmbeddedDatabaseFactory : Starting embedded database: > url='jdbc:h2:mem:2784768e-f053-4bb3-ab88-edda34956893;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=false', > username='sa'

Note: I still have 'spring-jpa' properties defined in 'application.properties' and I don't use any profiles. @AutoConfigureTestDatabase will override existing jpa configurations with test defaults AutoConfigureTestDatabase.Replace.

Simplest solution:

1. in src/main/resources have application.properties (production config):

   spring.datasource.url=jdbc:mysql://localhost:3306/somedb spring.datasource.username=root spring.datasource.password=password spring.datasource.driverClassName=com.mysql.jdbc.Driver spring.jpa.database-platform = org.hibernate.dialect.MySQL5Dialect

and application-test.properties with HSQL config like:

spring.jpa.hibernate.ddl-auto = create-drop
spring.jpa.database = HSQL
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.HSQLDialect
spring.datasource.driverClassName = org.hsqldb.jdbcDriver
spring.datasource.url= jdbc:hsqldb:mem:scratchdb
spring.datasource.username = sa
spring.datasource.password =

2) Add HSQL dependency in pom.xml if you don't have it already.

3. Annotate your test class with @ActiveProfiles("test").

Worked like charm in my case.

@Sanjay has one way to put it but I find it confusing. You could just as well have only a production profile that you enable when you're in production, something like:

spring.jpa.hibernate.ddl-auto: update
spring.datasource.url: jdbc:mysql://localhost:3306/dbname
spring.datasource.username: username
spring.datasource.password: password

And don't specify anything else. If you add an embedded database in test scope, it will be available in your tests. If you run your tests with the default profile (no customization whatsoever), it won't find any database information (since these are stored in the production profile). In that case, it will try to find an embedded database and start it for you. If you need more customization for some reason, you can have a application-test.properties for those (you'll need to add ActiveProfiles("test") to your test(s).

Simple solution if building with maven: just place an application.properties file under src/test/resources and edit as appropriate for testing.

The Spring (Boot) Profile mechanism is a pretty powerful tool that, in scope, goes way beyond "swapping settings between test time and run time". Although, clearly, as demonstrated, it can do that also :)

This solution enables common settings for develop and test. Is based on this solution: Override default Spring-Boot application.properties settings in Junit Test

1. application.properties in src/main/resources/application.properties

    #common settings for DEVELOPMENT and TEST:
    ......
    ......

    ## Spring DATASOURCE (DataSourceAutoConfiguration & DataSourceProperties)
    spring.datasource.url=jdbc:postgresql://localhost:5432/databasename
    spring.datasource.username=postgres
    spring.datasource.password=somepassword

    # The SQL dialect makes Hibernate generate better SQL for the chosen database
    spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect
    spring.jpa.properties.hibernate.jdbc.time_zone=UTC

    # Hibernate ddl auto (create, create-drop, validate, update)
    spring.jpa.hibernate.ddl-auto = none
    spring.jpa.properties.hibernate.jdbc.lob.non_contextual_creation=true

2. test.properties (src/main/resources/application.properties) which overrides and adds properties in application.properties:

    spring.datasource.url=jdbc:h2:mem:testdb;MODE=PostgreSQL
    spring.datasource.driverClassName=org.h2.Driver
    spring.datasource.username=sa
    spring.datasource.password=
    spring.jpa.hibernate.ddl-auto=update
    spring.h2.console.enabled=false

3. settings in pom.xml for H2 and Postgre databases

      <!-- h2 -->
      <dependency>
        <groupId>com.h2database</groupId>
        <artifactId>h2</artifactId>
      </dependency>

    <!-- postgress -->
      <dependency>
         <groupId>org.postgresql</groupId>
         <artifactId>postgresql</artifactId>
      </dependency>

4. In test class:

    @RunWith(SpringRunner.class)
    @SpringBootTest
    @TestPropertySource(locations = "classpath:test.properties")
    public class ModelTest { 

    }

I have a multi-module Gradle SpringBootApplication with below Modules

1. employeemanagerApp - Where my SpringApplication main class
2. employeemanagerIntTests - Where i have my cucumber tests

My requirement was to use MySQL DB when the application boots up and H2 during my Cucumber Integration testing

Solution: In my employeemanagerApp module, src/main/resources i placed the application.properties with below content

#My SQL Configuration
spring.datasource.url=jdbc:mysql://localhost:3306/employeemanager
spring.datasource.username=root
spring.datasource.password=password
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=update  spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect

And in the Integration Test Module (employeemanagerIntTests) src/test/resources I placed the application.properties with below content

#H2 In-Memory DB Configuration
spring.datasource.url=jdbc:h2://mem:db;DB_CLOSE_DELAY=-1
spring.datasource.username=sa
spring.datasource.password=sa
spring.datasource.driver-class-name=org.h2.Driver
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
spring.jpa.properties.hibernate.format_sql=true

And in my Step Definition Class i added only these annotations

@CucumberContextConfiguration
@SpringBootTest(classes = SpringBootApplicationMainClass.class, webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)

In the build.gradle file i added H2 dependency

testImplementation 'com.h2database:h2:1.4.200'

So when I ran my tests, H2 was active and all tests with Create, Update, Read and Delete were successful