Using Coverage in Maven

Since MUnit 2.x, the coverage report goal is integrated with the maven reporting section. Coverage Reports are generated during Maven’s site lifecycle, during the coverage-report goal.

<plugin>
    <groupId>com.mulesoft.munit.tools</groupId>
    <artifactId>munit-maven-plugin</artifactId>
    <version>${project.version}</version>
    <executions>
        <execution>
            <id>test</id>
            <phase>test</phase>
            <goals>
                <goal>test</goal>
                <goal>coverage-report</goal>
            </goals>
        </execution>
    </executions>
    <configuration>
        <coverage>
            <runCoverage>true</runCoverage>
            <failBuild>false</failBuild>
            <requiredApplicationCoverage>0</requiredApplicationCoverage>
            <requiredResourceCoverage>0</requiredResourceCoverage>
            <requiredFlowCoverage>0</requiredFlowCoverage>
            <formats>
                <format>console</format>
                <format>html</format>
            </formats>
        </coverage>
    </configuration>
</plugin>

Coverage Report Types

When enabling MUnit Coverage, you see a summary report in the console. By default, no other action is taken:

[INFO] ===============================================================================
[INFO] 				MUnit Coverage Report
[INFO] ===============================================================================
[NOTE]
[INFO] -------------------------------------------------------------------------------
[INFO] Resource File: mule-app.xml - Flows: 1 - Weight: 100.00 -  Coverage: 100.00%
[INFO] -------------------------------------------------------------------------------
[INFO]   * Flow: muleFlow - Covered (MP): 2 - Total (MP): 2 - Coverage: 100.00%
[NOTE]
[INFO] ===============================================================================
[INFO] 					Summary
[INFO] ===============================================================================
[INFO]   * CMPs: 2
[INFO]   * MPs: 2
[INFO]   * Flows: 1
[INFO]   * Resources: 1
[INFO] ===============================================================================
[INFO] 				** Application Coverage: 100.00% **
[INFO] ===============================================================================
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 27.462 s
[INFO] Finished at: yyyy-mm-ddThh:mm:ss
[INFO] Final Memory: 20M/379M
[INFO] ------------------------------------------------------------------------

MUnit Coverage offers three types of reports:

The Console report is printed to the console. It works with the summary report and shows an overview of the MUnit run, with a count of all resources, flows, and processors, as well as the overall application coverage level, and warnings and errors if any.
The HTML report shows the same information but formatted to fit any web browser.
To access the report, browse your application folder structure to the ${application.path}/target/site/munit/coverage/ path and locate the file summary.html at the starting point of the report and to navigate through all the data.
The JSON report shows the same information as the HTML report, in a JSON format.
To access the JSON report locate the ${application.path}/target/site/munit/coverage/munit-coverage.json fileinside your application folder structure.

To enable the report generation, add the following configuration:

MUnit Coverage - Report Configuration

<coverage>
  <runCoverage>true</runCoverage>

  <formats>
    <format>console</format>  (1)
    <format>html</format>     (2)
    <format>json</format>     (3)
  </formats>
</coverage>

1	Console report
2	HTML report
3	JSON report

You can have none, one, or all the report types added to your configuration.

To configure, for example, the JSON report generation, you need to add the following configuration in your pom.xml file:

<coverage>
<runCoverage>true</runCoverage>
  <formats>
    <format>json</format>
  </formats>
</coverage>

Configuring Coverage Requirements

One of the features of MUnit Coverage is to fail the build if a certain coverage level is not reached.

MUnit Coverage handles three different levels:

Application: The overall coverage of all your application.
Resource: The coverage level of each individual Mule configuration file.
Flow: The coverage of event processors in each flow.

To define the required coverage levels:

MUnit Coverage - Require Coverage

<coverage>
    <runCoverage>true</runCoverage>
    <failBuild>true</failBuild>

    <requiredApplicationCoverage>75</requiredApplicationCoverage> (1)
    <requiredResourceCoverage>50</requiredResourceCoverage>
    <requiredFlowCoverage>50</requiredFlowCoverage>
</coverage>

1	Each value represents a percentage. If a percentage is not defined, it defaults to -1, which indicates that no requirements are defined for said level so the build will not fail due to low coverage.

If you define coverage levels but set the property failBuild to false, and then the levels are not reached, a warning shows up in the MUnit coverage summary:

===============================================================================
MUnit Coverage Summary
===============================================================================
 * Resources: 2 - Flows: 3 - Processors: 4
 * Application Coverage: 75.00%

----------------------------- WARNING --------------------------------------
 * Flow: file2.xml -> file2Flow1 coverage is below defined limit. Required: 50.0% - Current: 00.00% (1)
====================================================================================

1	Warning detailing which coverage level was not met, and where it happened.

Ignoring a flow or a file

Another feature is the ability to ignore either a flow or a file. This way, the ignored resource:

Does not count as coverage data.
Does not affect the overall number of message processors.
Does not cause a build to fail if the flow is not tested or if the flow does not reach coverage metrics.

To ignore flows and files:

MUnit Coverage - Ignore both flows and files

<coverage>
    <runCoverage>true</runCoverage>
    <failBuild>true</failBuild>

    <requiredApplicationCoverage>100</requiredApplicationCoverage>
    <requiredResourceCoverage>100</requiredResourceCoverage>
    <requiredFlowCoverage>100</requiredFlowCoverage>

    <ignoreFlows>
        <ignoreFlow>flow-1</ignoreFlow>
        <ignoreFlow>flow-2</ignoreFlow>
        ...
        <ignoreFlow>flow-n</ignoreFlow>
    </ignoreFlows>

    <ignoreFiles>
        <ignoreFile>mule-config-1.xml</ignoreFile>
        <ignoreFile>mule-config-2.xml</ignoreFile>
        ...
        <ignoreFile>mule-config-n.xml</ignoreFile>
    </ignoreFiles>
</coverage>