Enabling code coverage : in Sonar, from Jenkins, with Maven, using Jacoco.

Let’s assume a few think before we begin.

• SonarQube is installed somewhere and works.
• The task « Invoke Standalone Sonar Analysis » is available in Jenkins.
• Your project is using Maven so it has a pom.xml.

To begin, we’ll add configuration in our pom.xml.

<properties>
  <sonar.core.codeCoveragePlugin>jacoco</sonar.core.codeCoveragePlugin>
  <sonar.jacoco.reportPath>${project.basedir}/../target/jacoco.exec</sonar.jacoco.reportPath>
  <sonar.language>java</sonar.language>
</properties>

We’re using JUnit to run tests.

<dependencies>
  <dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.11</version>
    <scope>test</scope>
  </dependency>
</dependencies>

Now, we configure our plugins.

<build>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-surefire-plugin</artifactId>
      <version>2.18.1</version>
    </plugin>
    <plugin>
      <groupId>org.jacoco</groupId>
      <artifactId>jacoco-maven-plugin</artifactId>
      <version>0.7.2.201409121644</version>
      <configuration>
        <append>true</append>
      </configuration>
      <executions>
        <execution>
          <goals>
            <goal>prepare-agent</goal>
          </goals>
        </execution>
        <execution>
          <id>post-unit-test</id>
          <phase>test</phase>
          <goals>
            <goal>report</goal>
          </goals>
        </execution>
      </executions>
    </plugin>
  </plugins>
</build>

Everything should be good regarding Maven configuration, so we’ll switch to Jenkins configuration. In your job, you should add the task « Invoke Standalone Sonar Analysis ». The interesting part is the « project properties » field.

# Metadata
sonar.projectName=${JOB_NAME}
sonar.projectVersion=1.0.0

# Source information
sonar.sources=src/main
sonar.sourceEncoding=UTF-8
sonar.language=java

# Tests
sonar.tests=src/test
sonar.junit.reportsPath=target/surefire-reports
sonar.surefire.reportsPath=target/surefire-reports
sonar.jacoco.reportPath=target/jacoco.exec
sonar.binaries=target/classes
sonar.java.coveragePlugin=jacoco

# Debug
sonar.verbose=true

Don’t forget sonar.binaries, otherwise, you might get something like « Project coverage is set to 0% since there is no directories with classes. » in your logs.

In addition, if I’m doing a mvn clean test, I get the following files in directory target (among others):

• classes/
• surefire-reports/
• jacoco.exec

Using this setup, I manage to display information regarding test coverage and test execution. Besides, there might be some duplicate as for sonar.surefire.reportsPath and sonar.junit.reportsPath in sonar properties.