- Cucable Maven Plugin
- Typical workflow
- Example project
- Additional Information
Cucable is a Maven plugin for Cucumber scenarios that simplifies fine-grained and efficient parallel test runs.
This plugin does the following:
- Generate single Cucumber features containing one single scenario each
- Convert scenario outlines into separate scenarios
- Generating Cucumber runners for every generated "single scenario" feature file
Those generated runners and features can then be used with Maven Failsafe in order to parallelize test runs.
Note: From version 0.1.7 on this also works for non-english feature files!
- plugin-code contains the full plugin source code.
- example-project contains an example Maven project to see the plugin in action.
All changes are documented in the full changelog.
<dependency>
<groupId>com.trivago.rta</groupId>
<artifactId>cucable-plugin</artifactId>
<version>(check version on top of the page)</version>
</dependency>
- Generation of runners and features
- Running the generated tests with Maven failsafe
- Aggregation of a single test report after all test runs
The following sections break down the above steps.
<plugin>
<groupId>com.trivago.rta</groupId>
<artifactId>cucable-plugin</artifactId>
<version>${cucable-plugin.version}</version>
<executions>
<execution>
<id>generate-test-resources</id>
<phase>generate-test-resources</phase>
<goals>
<goal>parallel</goal>
</goals>
</execution>
</executions>
<configuration>
<!-- Required properties -->
<sourceRunnerTemplateFile>src/test/resources/parallel/cucable.template</sourceRunnerTemplateFile>
<sourceFeatures>src/test/resources/features</sourceFeatures>
<generatedFeatureDirectory>src/test/resources/parallel/features</generatedFeatureDirectory>
<generatedRunnerDirectory>src/test/java/parallel/runners</generatedRunnerDirectory>
<!-- Optional properties -->
<numberOfTestRuns>1</numberOfTestRuns>
<includeScenarioTags>
<param>@includeMe</param>
<param>@includeMeAsWell</param>
</includeScenarioTags>
<excludeScenarioTags>
<param>@skip</param>
</excludeScenarioTags>
<logLevel>compact</logLevel>
</configuration>
</plugin>
The specified file will be used to generate runners for every generated feature file.
This can be either a text file or a Java class. The difference is outlined below:
If you use a java file (e.g. src/test/java/some/template/CucableJavaTemplate.java), all [FEATURE_FILE_NAME] placeholders as well as the class name will be substituted for the generated feature file name. Also, the package declaration will be stripped.
Example:
package some.template; import cucumber.api.CucumberOptions; @CucumberOptions( features = {"target/parallel/features/[FEATURE_FILE_NAME].feature"}, plugin = {"json:target/cucumber-report/[FEATURE_FILE_NAME].json"} ) public class CucableJavaTemplate { }
will turn into
import cucumber.api.CucumberOptions; @CucumberOptions( features = {"target/parallel/features/MyFeature_scenario001_run001_IT.feature"}, plugin = {"json:target/cucumber-report/MyFeature_scenario001_run001_IT.json"} ) public class MyFeature_scenario001_run001_IT { }
If you use a text file (e.g. src/test/resources/cucable.template), all [FEATURE_FILE_NAME] placeholders will be substituted for the generated feature file name.
Example:
import cucumber.api.CucumberOptions; @CucumberOptions( features = {"target/parallel/features/[FEATURE_FILE_NAME].feature"}, plugin = {"json:target/cucumber-report/[FEATURE_FILE_NAME].json"} ) public class [FEATURE_FILE_NAME] { }
will turn into
import cucumber.api.CucumberOptions; @CucumberOptions( features = {"target/parallel/features/MyFeature_scenario001_run001_IT.feature"}, plugin = {"json:target/cucumber-report/MyFeature_scenario001_run001_IT.json"} ) public class MyFeature_scenario001_run001_IT { }
This can specify
- the root path of your existing Cucumber .feature files (e.g.
src/test/resources/features
) - the path to a specific existing Cucumber .feature file (e.g.
src/test/resources/features/MyFeature.feature
) - the path to a specific existing Cucumber .feature file including line numbers of specific scenarios/scenario outlines inside this file (e.g.
src/test/resources/features/MyFeature.feature:12:19
would only convert the scenarios starting at line 12 and 19 inside MyFeature.feature)
The path where the generated Cucumber .feature files should be located (e.g. src/test/resources/parallel).
Note: This directory should be located under a valid resource folder to be included as a test source by Maven. If you want to use a directory inside Maven's target folder, check this example.
Caution: This directory will be wiped prior to the feature file generation!
The path where the generated runner classes should be located (e.g. src/test/java/parallel/runners).
Note: This directory should be located under a valid source folder to be included as a test source by Maven. If you want to use a directory inside Maven's target folder, check this example.
Caution: This directory will be wiped prior to the runner file generation!
Optional number of test runs. If it is not set, its default value is 1. For each test run, the whole set of features and runners is generated like this:
- MyFeature_scenario001_run001_IT.feature
- MyFeature_scenario001_run002_IT.feature
- MyFeature_scenario001_run003_IT.feature
- etc.
Note: Characters other than letters from A to Z, numbers and underscores will be stripped out of the feature file name.
Optional scenario tags that should be included in the feature and runner generation.
To include multiple tags, just add each one into as its own <param>
:
<includeScenarioTags>
<param>@scenario1Tag1</param>
<param>@scenario1Tag2</param>
</includeScenarioTags>
Note: When using includeScenarioTags and excludeScenarioTags together, the excludeScenarioTags will override the includeScenarioTags. This means that a scenario containing an included tag and an excluded tag will be excluded!
Optional scenario tags that should not be included in the feature and runner generation.
To include multiple tags, just add each one into as its own <param>
:
<excludeScenarioTags>
<param>@tag1</param>
<param>@tag2</param>
</excludeScenarioTags>
Note: When using includeScenarioTags and excludeScenarioTags together, the excludeScenarioTags will override the includeScenarioTags. This means that a scenario containing an included tag and an excluded tag will be excluded!
By default, Cucable logs all information including
- its own name and version
- all passed property values
- a list of processed feature paths
This can be configured by passing the logLevel
property:
<logLevel>default|compact|minimal|off</logLevel>
- default will log all the mentioned information
- compact will only log the plugin name, version, properties and one line of summary
- minimal will only log a summary line
- off will prevent any logging
It may be desirable for you to generate the Cucable features and runners in Maven's target
directory.
The advantage of this is that this directory is wiped by the mvn clean
command and older generated files do not reside in your src
directory.
In order to achieve this, you can specify subdirectories under target (${project.build.directory}
) for Cucable, e.g. ${project.build.directory}/parallel/runners
and ${project.build.directory}/parallel/features
After this step, use the build-helper-maven-plugin in your POM file in order to consider the generated runner classes test sources:
<plugins>
<plugin>
<groupId>com.trivago.rta</groupId>
<artifactId>cucable-plugin</artifactId>
<version>${cucable.plugin.version}</version>
<executions>
<execution>
<id>generate-test-resources</id>
<phase>generate-test-resources</phase>
<goals>
<goal>parallel</goal>
</goals>
</execution>
</executions>
<configuration>
<sourceRunnerTemplateFile>path_to_template_file</sourceRunnerTemplateFile>
<sourceFeatures>path_to_features</sourceFeatures>
<generatedFeatureDirectory>${project.build.directory}/parallel/features</generatedFeatureDirectory>
<generatedRunnerDirectory>${project.build.directory}/parallel/runners</generatedRunnerDirectory>
</configuration>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>build-helper-maven-plugin</artifactId>
<version>${build.helper.plugin.version}</version>
<executions>
<execution>
<id>add-test-source</id>
<phase>generate-test-sources</phase>
<goals>
<goal>add-test-source</goal>
</goals>
</execution>
</executions>
<configuration>
<sources>
<source>${project.build.directory}/parallel/runners</source>
</sources>
</configuration>
</plugin>
</plugins>
Below, you can see a full example of what Cucable does.
This is our source feature file. It contains a scenario and a scenario outline with two examples.
MyFeature.feature
Feature: This is the feature name
Scenario: First scenario
Given I am on the start page
And I click the login button
Then I see an error message
Scenario Outline: Second scenario with an amount of <amount>
Given I am on the start page
And I add <amount> items
And I navigate to the shopping basket
Then I see <amount> items
Examples:
| amount |
| 12 |
| 85 |
This is the runner template file that is used to generate single scenario runners. The placeholder [FEATURE_FILE_NAME] will be replaced with generated feature names by Cucable.
import cucumber.api.CucumberOptions; @CucumberOptions( features = {"target/parallel/features/[FEATURE_FILE_NAME].feature"}, plugin = {"json:target/cucumber-report/[FEATURE_FILE_NAME].json"} ) public class [FEATURE_FILE_NAME] { }
Note: The specified plugin generates Cucumber JSON files which are needed for custom aggregated test reports.
For each scenario, a single feature file is created:
MyFeature_scenario001_run001_IT.feature
Feature: This is the feature name
Scenario: First scenario
Given I am on the start page
And I click the login button
Then I see an error message
Note that for the scenario outlines, each example is converted to its own scenario and feature file:
MyFeature_scenario002_run001_IT.feature
Feature: This is the feature name Scenario: Second scenario with an amount of 12 Given I am on the start page And I add 12 items And I navigate to the shopping basket Then I see 12 items
MyFeature_scenario003_run001_IT.feature
Feature: This is the feature name Scenario: Second scenario with an amount of 85 Given I am on the start page And I add 85 items And I navigate to the shopping basket Then I see 85 items
The generated runners point to each one of the generated feature files.
This is an example for one of the generated runners - note how the placeholders are now replaced with the name of the feature to run:
MyFeature_scenario001_run001_IT.java
import cucumber.api.CucumberOptions; @CucumberOptions( features = {"target/parallel/features/MyFeature_scenario001_run001_IT.feature"}, plugin = {"json:target/cucumber-report/MyFeature_scenario001_run001_IT.json"} ) public class MyFeature_scenario001_run001_IT { }
This will skip the unit tests (if any) and run the generated runner classes with Failsafe. Since all generated runner classes from the step before end with _IT, they are automatically considered integration tests and run with failsafe.
Note: If all tests should be run regardless of their result, it is important to set <testFailureIgnore>true</testFailureIgnore>
for Failsafe - otherwise the plugin execution will stop on failing tests.
However, if this is specified, the build will not fail in case of failing tests!
To circumvent that, it is possible to specify a custom rule for Maven enforcer that passes or fails the build depending on custom conditions.
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<skipTests>true</skipTests>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-failsafe-plugin</artifactId>
<executions>
<execution>
<id>Run parallel tests</id>
<phase>integration-test</phase>
<goals>
<goal>integration-test</goal>
</goals>
</execution>
</executions>
<configuration>
<testFailureIgnore>true</testFailureIgnore>
<forkCount>${maven.fork.count}</forkCount>
<reuseForks>false</reuseForks>
<argLine>-Dfile.encoding=UTF-8</argLine>
<disableXmlReport>true</disableXmlReport>
</configuration>
</plugin>
</plugins>
We use the Cluecumber plugin to aggregate all generated .json report files into one overall test report.
<plugins>
<plugin>
<groupId>com.trivago.rta</groupId>
<artifactId>cluecumber-report-plugin</artifactId>
<version>${cluecumber.report.version}</version>
<executions>
<execution>
<id>report</id>
<phase>post-integration-test</phase>
<goals>
<goal>reporting</goal>
</goals>
</execution>
</executions>
<configuration>
<sourceJsonReportDirectory>${project.build.directory}/cucumber-report</sourceJsonReportDirectory>
<generatedHtmlReportDirectory>${project.build.directory}/test-report</generatedHtmlReportDirectory>
</configuration>
</plugin>
</plugins>
You can test the complete flow and POM configuration by checking out the Cucable example project.
Cucable requires Java >= 8 and Maven >= 3.3.9. It is available in Maven central.
Copyright 2017 trivago N.V.
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
This plugin was inspired by the Cucumber Slices Maven Plugin.
This project is being tested on