on Jan 17th, 2012Continuous Integration Tests for REST APIs with Maven, Jetty and restfuse
As you might know from previous posts, most of my work time has something to do with the development of REST based systems. The systems we develop are mostly written in Java. To ensure that a system works, we have a step in our continuous integration process that executes integration tests before automated deployment is launched. With this short post I’d like to show you our setup for these integration tests because when I searched a few months ago the results were rare.
We write integration tests for REST systems with JUnit and restfuse. Check this post for a how-to on restfuse. Thanks to the Maven surefire plugin we can simply execute these tests in our maven build. Here is the build and dependency section of the test module’s pom.
<build> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-surefire-plugin</artifactId> <version>2.9</version> <executions> <execution> <id>test</id> <phase>test</phase> <configuration> <testClassesDirectory>${project.build.outputDirectory}</testClassesDirectory> </configuration> <goals> <goal>test</goal> </goals> </execution> </executions> </plugin> ... </plugins> </build> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.8.1</version> <scope>test</scope> </dependency> <dependency> <groupId>com.restfuse</groupId> <artifactId>com.eclipsesource.restfuse</artifactId> <version>1.0.0</version> </dependency> </dependencies>
Most of our Java-REST applications ship as war files. So, at this stage the question becomes, “How can I test the war file I just built?” One answer is to hot deploy the war file and run the tests against it. But, for a hot deployment we need a server running tomcat (or another servlet container), right? Actually, we don’t 
. We can simply embed a Jetty plugin into our maven build, start it and deploy our war file using the Maven Jetty plugin. The related section in the pom looks like this:
<build> <plugins> ... <plugin> <groupId>org.mortbay.jetty</groupId> <artifactId>maven-jetty-plugin</artifactId> <version>${jetty-version}</version> <configuration> <scanIntervalSeconds>10</scanIntervalSeconds> <stopKey>foo</stopKey> <stopPort>9090</stopPort> <contextPath>/</contextPath> <tmpDirectory>/tmp/work/</tmpDirectory> <webApp>/tmp/test.war</webApp> <daemon>true</daemon> <reload>manual</reload> </configuration> <executions> <execution> <id>start-jetty</id> <phase>test-compile</phase> <goals> <goal>deploy-war</goal> </goals> </execution> <execution> <id>stop-jetty</id> <phase>verify</phase> <goals> <goal>stop</goal> </goals> </execution> </executions> </plugin> ... </plugins> </build>
It is important that we deploy the war file before the actual test phase, in our example, during test-compile. To make this work we need to copy the new war file into the configured directory before we run the maven build. This can be accomplished with a simple shell script. The following snippet shows how it looked for our jenkins job:
rm -rf /tmp/work mkdir /tmp/work cp $WORKSPACE/../job/**/*.war /tmp/test.war
A few last points. In our setup we split the integration test build from the main build but you can merge them together as well. And, when using restfuse an important thing to keep in mind is that you need to configure the port to be the same as the one jetty uses to run the tests.
That’s it – short but efficient. Maybe you have a similar approach to share in a comment with us?
