External Rules
This rule will provide rules configuration from an external resource.
It can be a classpath resource present in a maven-enforcer-plugin dependency or a local file.
Sample Plugin Configuration:
<project>
[...]
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-enforcer-plugin</artifactId>
<version>3.5.0</version>
<dependencies>
<!-- Dependency containing the enforcer/rules.xml file -->
<dependency>
<groupId>org.foo</groupId>
<artifactId>foobar-rules</artifactId>
<version>1.0.0</version>
</dependency>
</dependencies>
<executions>
<execution>
<id>enforce</id>
<goals>
<goal>enforce</goal>
</goals>
<configuration>
<rules>
<externalRules>
<!-- enforcer/rules.xml is supposed to be a classpath resource present -->
<!-- in org.foo:foobar-rules dependency of maven-enforcer-plugin defined above -->
<location>classpath:enforcer/rules.xml</location>
</externalRules>
<externalRules>
<!-- You can add multiple <ExternalRules> elements if you need to enforce -->
<!-- rules from multiple resources. -->
<!-- src/build/rules.xml is a local file path relative to ${project.basedir} -->
<location>src/build/rules.xml</location>
</externalRules>
</rules>
<fail>true</fail>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
[...]
</project>The External Enforcer Rule Descriptor
Here is a sample rules file. The rules element expects the same content as in the Enforcer Mojo rules configuration:
<enforcer>
<rules>
<dependencyConvergence/>
<bannedDependencies>
<excludes>
<exclude>org.jboss.spec.javax.annotation:jboss-annotations-api_1.2_spec</exclude>
</excludes>
<includes>
<include>jakarta.xml.bind:jakarta.xml.bind-api:*:*:test</include>
</includes>
</bannedDependencies>
</rules>
</enforcer>