Testing GWT Libraries with Selenium and Maven
On Tuesday, I wrote about Running Hosted Mode in GWT Libraries. Today I added an additional module to our project to run Selenium tests against our GWT library. In the process, I discovered some things I needed to modify in my GWT library's pom.xml. I'm writing this post so others can use this setup to write GWT libraries and package them for testing with Selenium.
First of all, I noticed that when you're using the GWT Maven Plugin with a JAR project, it doesn't automatically run gwt:compile or gwt:test in the compile and test phases. I had to explicitly configure the compile goal to run in the compile phase. I also had to add <webappDirectory> to the configuration to compile the JavaScript files into the war directory.
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>gwt-maven-plugin</artifactId>
<version>1.1</version>
<configuration>
<module>org.appfuse.gwt.core.CoreUI</module>
<runTarget>index.html</runTarget>
<webappDirectory>war</webappDirectory>
</configuration>
<executions>
<execution>
<phase>compile</phase>
<goals>
<goal>compile</goal>
</goals>
</execution>
</executions>
</plugin>
To package the generated JavaScript and index.html in the JAR, I added the following <resources> section to the maven-resources-plugin configuration I mentioned in my previous post.
<resource>
<directory>war</directory>
<includes>
<include>core.ui/**</include>
<include>index.html</include>
</includes>
</resource>
In addition, I discovered some javax.servlet.* classes in my JAR after running "mvn package". I believe this is caused by the GWT plugin sucking these in when it compiles my ProxyServlet. I excluded them by adding the maven-jar-plugin.
<plugin>
<artifactId>maven-jar-plugin</artifactId>
<configuration>
<excludes>
<exclude>javax/servlet/**</exclude>
</excludes>
</configuration>
</plugin>
After doing this, I was able to publish my JAR with all the contents I needed to run Selenium tests against it.
Testing the GWT Library with Selenium
The module that contains the Selenium tests is a WAR project that uses war overlays, Cargo and Selenium RC. You can read about the Maven setup I use for running Selenium tests in Packaging a SOFEA Application for Distribution.
The major difference when testing a JAR (vs. a WAR), is I had to use the maven-dependency-plugin to unpack the JAR so its contents would get included in the WAR for testing. Below is the configuration I used to accomplish this:
<plugin>
<artifactId>maven-dependency-plugin</artifactId>
<executions>
<execution>
<id>unpack</id>
<phase>generate-sources</phase>
<goals>
<goal>unpack</goal>
</goals>
<configuration>
<artifactItems>
<artifactItem>
<groupId>org.appfuse</groupId>
<artifactId>gwt-core</artifactId>
<version>1.0-SNAPSHOT</version>
<type>jar</type>
<overWrite>false</overWrite>
<excludes>META-INF/**,org/**,javax/**</excludes>
</artifactItem>
</artifactItems>
<outputDirectory>
${project.build.directory}/${project.build.finalName}
</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
Hopefully this will help you develop GWT libraries and run Selenium tests against them. If you have any suggestions for simplifying this configuration, please let me know.
NOTE: I did considering a couple of other options for running Selenium tests against our GWT library:
- Add something to the existing project that 1) creates a WAR and 2) fires up Cargo/Selenium in a profile to test it.
- Create the tests in a GWT (war) project that includes widgets from the library.
I decided on the solution documented above because it seemed like the best option.