JarCasting
cucumber2junit-maven-plugin
Background
There are various cloud services which allow running automated tests on simulated or real mobile devices. One of them is AWS Device Farm. Their solution requires uploading the whole test code including all dependencies. This reduces the execution time but also limits the flexibility of how to execute tests.
One major drawback is that when using Appium and JUnit there is no support for custom test runners. However, a custom runner (namely cucumber.api.junit.Cucumberor an extension of it) is the default way to run Cucumber features with JUnit. Until AWS officially supports Cucumber, there is no straightforward way to run them on their public device farm. They offer dedicated private devices as well which give you full access and therefore also allow running Cucumber tests against. This, however, comes at a different price tag.
Solution
This Maven plugin offers a workaround. It parses the feature files in a Java project and generates plain JUnit test classes which can be run on public devices within the AWS Device Farm.
Configuration
Add the following configuration in the pom.xml of your project:
<profiles>
<profile>
<id>aws</id>
<build>
<plugins>
<plugin>
<groupId>io.github.martinschneider</groupId>
<artifactId>cucumber2junit-maven-plugin</artifactId>
<version>1.2</version>
<executions>
<execution>
<id>aws</id>
<phase>generate-sources</phase>
<goals>
<goal>generate</goal>
</goals>
<configuration>
<packageName>io.github.martinschneider.demo.tests</packageName>
<stepsPackageName>io.github.martinschneider.demo.steps</stepsPackageName>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</profile>
</profiles>
packageName and stepsPackageName are the only mandatory parameters but in almost all cases you want to overwrite the default template too:
<templatePath>/path/to/custom/template.vm</templatePath>
This is the path to a velocity template which will be used for generating the JUnit test code. See junitTestClass.vm for the default.
Here are the other possible configuration parameter with their respective default values:
<featuresSourceDirectory>${project.basedir}/src/test/resources/features</featuresSourceDirectory>
<javaOutputDirectory>${project.basedir}/src/test/java</javaOutputDirectory>
<featuresClasspath>features</featuresClasspath>
<featuresOutputDirectory>"/tmp/features"</featuresOutputDirectory>
Make sure that the featuresOutputDirectory points to a directory that you are allowed to write to in your AWS setup.
Also, add the configuration detailed in the AWS documentation to package your project and all dependencies into a single zip-file.
Usage
Then simply run mvn -Paws package -DskipTests=true. This will result in a zip-file which can be used to run your tests within the AWS Device Farm.
Additional documentation
Customising the Velocity template
This plugin uses Apache Velocity to generate Java source code. You can customise the template to the specific needs of your project. For example you might to execute custom code before every test execution.
You can use the following placeholders within the template:
classNamethe name of the test class (derived from the name of the feature)packageNamethe package for the JUnit testsfeaturesSourceDirectorythe absolute path to the feature filesjavaOutputDirectorythe absolute path to write the JUnit tests tofeaturethe feature object (see ... for the public methods it exposes)featuresOutputDirectorythe absolute path to write the feature files tofeaturesClasspath, the classpath to load the feature files fromscenariosthe scenarios (see ... for the Java code)stepsPackagethe package including the glue code (steps)
The (absolute) path to the template file can be set in the configuration of the plugin.
<templatePath>/path/to/custom/template.vm</templatePath>
If it is not specified the default will be used.
Additional placeholders
You can also define a map of additional placeholders for the velocity template:
<configuration>
...
<additionalPlaceholders>
<key1>value1</key1>
<key2>value2</key2>
</additionalPlaceholders>
...
</configuration>
Maven resolves system properties within the values so the following example works as well:
<additionalPlaceholders>
<key>${someSystemProp}</key>
</additionalPlaceholders>
You can then pass the value as a parameter when packaging your project: mvn -Paws -DsomeSystemProp=value package -DskipTests=true.
All occurences of $key will then be replaced with value when processing the template..
Contact
Martin Schneider, [email protected]
