Starting an H2 Database Server from Maven?

Question

Sorry if this question is nonsensical, I'm still wrapping my head around new concepts.

Suppose I want to create and use an H2 database for my integration tests. Maven has a command to run tests: mvn test. Is there a way to tell maven to start an H2 database server for the tests and stop it when it's done? I imagine this working similar to how I can run tomcat via a Maven command (mvn tomcat:run).

Answer 1

Since H2 doesn't provide Maven plugin you should start it using maven-antrun-plugin. Write code for start and stop h2 engine in ant task and call it when your integration test starts and stop.

See details on http://docs.codehaus.org/display/MAVENUSER/Maven+and+Integration+Testing

Answer 2

In my project, for unit testing, I asked Spring to handle this database creation and initialization. As stated in the H2 documentation, you can create a bean for that:

<bean id = "org.h2.tools.Server"
    class="org.h2.tools.Server"
    factory-method="createTcpServer"
    init-method="start"
    destroy-method="stop">
    <constructor-arg value="-tcp,-tcpAllowOthers,true,-tcpPort,8043" />
</bean>

You simply need to start the Spring context with this configuration when you start your unit tests.

Answer 3

you can create 2 small classes with main methods that start and stop the database. the idea is to run the StartServer class before the integration tests are run and then class StopServer after the tests have run.

you should do the same for your DB server as described somewhere in this document (description is for starting and stopping Jetty in integration tests)

in your pom.xml you should define the maven-exec-plugin to run the exec:java goal and create 2 executions (1 for calling StartServer and 1 for StopServer):

<plugin>
  <groupId>org.codehaus.mojo</groupId>
  <artifactId>exec-maven-plugin</artifactId>
  <version>1.1.1</version>
  <executions>
    <execution>
      <!-- start server before integration tests -->
      <id>start</id>
      <phase>pre-integration-test</phase>
      <goals>
        <goal>java</goal>
      </goals>
      <configuration>
        <mainClass>com.foo.StartServer</mainClass>
      </configuration>
     </execution>
     <execution>
      <!-- stop server after integration tests -->
      <id>stop</id>
      <phase>post-integration-test</phase>
      <goals>
        <goal>java</goal>
      </goals>
      <configuration>
        <mainClass>com.foo.StopServer</mainClass>
      </configuration>
     </execution>
   </executions>
 </plugin>

hope that's what you want

Answer 4

I was able to get it to work without using an external server just by adding the dependency to H2 via Maven and then using this bean:

<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="org.h2.Driver"/>
    <property name="url" value="jdbc:h2:file:h2\db"/>
    <property name="username" value="sa"/>
    <property name="password" value=""/>        
</bean>

Then again, this required that I use a file-based DB instead of in-memory. But it does the trick.