Introduction

Galvan is an integration test framework that lets developers test their code with a real Terracotta server. Galvan provides several APIs that will lets you control a Terracotta cluster from within your client test code. This document covers the configurations required and the basic usage of the APIs.

Configurations

Maven configuration

Add the following dependency to your project.

<dependency>
  <groupId>org.terracotta</groupId>
  <artifactId>galvan-support</artifactId>
  <version>1.0.3-beta</version>
  <scope>test</scope>
</dependency>

That’s all you’d need to use the Galvan APIs to control the cluster. Galvan provides a JUnit Rule implementation called BasicExternalCluster that you can use to easily manipulate a cluster. The following code sample demonstrates the usage of this rule:

public class GalvanTest {

  @Rule
  public static Cluster CLUSTER = new BasicExternalCluster(new File("target/cluster"), 2);  //(1)

  @Test
  public void testGalvanInteraction() throws Exception {
    IClusterControl clusterControl = CLUSTER.getClusterControl();  //(2)
    clusterControl.waitForActive(); //(3)
    clusterControl.waitForRunningPassivesInStandby();
    //Do your client behavior testing
    clusterControl.terminateOnePassive();
    clusterControl.terminateActive();
  }

1. Define the BasicExternalCluster rule by providing a working directory for the cluster and the number of servers you want in the stripe. This rule will start the cluster before each test method is executed and shutdown the cluster after the test execution completes, irrespective of the test result. If you don’t want the cluster to be started up and shutdown for every test, but only once for the entire test class, define it as a ClassRule.

2. Get hold of the IClusterControl instance from the cluster that really lets you control the servers in the cluster.

3. Invoke this method if you want to wait till the active server node is available before proceeding with your test.

BasicExternalCluster requires one mandatory configuration which is the path to a Terracotta server kit which it uses to startup the servers. Galvan looks up for a system property named kitInstallationPath for the kit location. This property can be provided by configuring the maven-surefire-plugin that runs the unit tests in your code base. Just add the following plugin configuration to your build:

      <plugin>
        <artifactId>maven-surefire-plugin</artifactId>
        <configuration>
          <systemPropertyVariables>
            <kitInstallationPath>${kitInstallationPath}</kitInstallationPath>
          </systemPropertyVariables>
        </configuration>
      </plugin>

Just replace ${kitInstallationPath} with the path to your kit location.

Auto downloading kit

Since BasicExternalCluster requires a kit location to run tests, it is advisable to have your build configured to auto download the kit as part of the build process. That can be done by configuring the maven-dependency-plugin for your build. The following configuration will download the kit and unzip it at a specified location during the process-test-resources phase so that the kit is available during the test phase.

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-dependency-plugin</artifactId>
  <executions>
    <execution>
      <id>unpack</id>
      <phase>process-test-resources</phase>
      <goals>
        <goal>unpack</goal>
      </goals>
      <configuration>
        <artifactItems>
          <artifactItem>
            <groupId>org.terracotta.internal</groupId>
            <artifactId>terracotta-kit</artifactId>
            <version>${kitVersion}</version>
            <type>zip</type>
            <outputDirectory>${kitUnzipLocation}</outputDirectory>
          </artifactItem>
        </artifactItems>
      </configuration>
    </execution>
  </executions>
</plugin>

Replace ${kitVersion} and ${kitUnzipLocation} to the values of your choice. The kitInstallationPath system property configuration value of the maven-surefire-plugin can be altered relative to the ${kitUnzipLocation} specified here.