Examples

Usage Example

If we take a real project and add the configuration for the Maven License Verifier Plugin into its pom like the following:

  <plugin>
    <groupId>com.soebes.maven.plugins.mlv</groupId>
    <artifactId>maven-license-verifier-plugin</artifactId>
    <version>0.4</version>
    <executions>
      <execution>
        <id>license-verifier</id>
        <goals>
          <goal>verify</goal>
        </goals>
      </execution>
    </exectuions>
  </plugin>

And of course create a licenses.xml file based on the modell with the following contents. 

<?xml version="1.0" encoding="UTF-8"?>
<licenses>
  <valid>
    <license>
      <id>Apache Software License 2.0</id>
      <description>Apache Software License 2.0</description>
      <names>
        <name>Apache 2</name>
        <name>Apache Software License 2.0</name>
        <name>Apache Software License, Version 2.0</name>
        <name>The Apache Software License, Version 2.0</name>
      </names>
      <urls>
        <url>http://www.apache.org/licenses/LICENSE-2.0</url>
        <url>http://www.apache.org/licenses/LICENSE-2.0.html</url>
        <url>http://www.apache.org/licenses/LICENSE-2.0.txt</url>
        <url>http://apache.org/licenses/LICENSE-2.0</url>
        <url>http://apache.org/licenses/LICENSE-2.0.html</url>
        <url>http://apache.org/licenses/LICENSE-2.0.txt</url>
        <url>LICENSE.txt</url>
      </urls>
    </license>
    <license>
      <id>Common Public License Version 1.0</id>
      <description>Common Public License Version 1.0</description>
      <names>
        <name>Common Public License Version 1.0</name>
      </names>
      <urls>
        <url>http://www.opensource.org/licenses/cpl1.0.txt</url>
      </urls>
    </license>
  </valid>

  <invalid>
    <license>
      <id>GNU General Public License (GPL)</id>
      <description>GNU General Public License (GPL)</description>
      <names>
        <name>GNU General Public License, version 2</name>
        <name>GNU General Public License, version 3</name>
      </names>
      <urls>
        <url>http://www.gnu.org/licenses/gpl-2.0.html</url>
        <url>http://www.gnu.org/licenses/gpl-3.0.txt</url>
      </urls>
    </license>
  </invalid>

  <warning>
    <license>
      <id>Apache Software License 1.1 (Historic)</id>
      <description>Apache Software License 1.1 (Historic)</description>
      <names>
        <name>Apache License, Version 1.1</name>
      </names>
      <urls>
        <url>http://www.apache.org/licenses/LICENSE-1.1</url>
      </urls>
    </license>
  </warning>
</licenses>

This will produce an output like the following the during a mvn clean package call (The output contains only an excerpt of the original output).

[INFO]
[INFO] --- maven-license-verifier-plugin:0.4:verify (license-verifier) @ sapm ---
[INFO] Loading /home/kama/ws-git/sapm/src/licenses/licenses.xml licenses file.
[WARNING] ]UNKNOWN[ (compile) The artifact antlr:antlr:jar:2.7.7 has a license which is categorized as unknown
[WARNING] ]UNKNOWN[ (compile) The artifact org.antlr:antlr-runtime:jar:3.3 has a license which is categorized as unknown
[WARNING] ]UNKNOWN[ (compile) The artifact org.antlr:stringtemplate:jar:3.2.1 has a license which is categorized as unknown
[WARNING] ]UNKNOWN[ (test) The artifact org.beanshell:bsh:jar:2.0b4 has a license which is categorized as unknown
[INFO]
[INFO] --- maven-jar-plugin:2.3.1:jar (default-jar) @ sapm ---
[INFO] Building jar: /home/kama/ws-git/sapm/target/sapm-0.5-SNAPSHOT.jar
[INFO]
[INFO] --- maven-site-plugin:3.0-beta-3:attach-descriptor (attach-descriptor) @ sapm ---
[INFO] Parent project loaded from repository.
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 14.103s
[INFO] Finished at: Sat Apr 30 16:49:48 CEST 2011
[INFO] Final Memory: 21M/212M
[INFO] ------------------------------------------------------------------------

Taking a closer look to the artifacts like the antlr:antlr:jar:2.7.7 you will find out that this artifact has a BSD License which is currently not in the licenses.xml file. This means in other words if we will accept the BSD license we have to add that license to the licenses.xml file in an appropriate category. The following will show you an appropriate excerpt of the licenses.xml file. In this case we put the license into Valid category.

  <valid>
    [...]
    <license>
      <id>BSD License</id>
      <description>BSD License</description>
      <names>
        <name>BSD License</name>
      </names>
      <urls>
        <url>http://www.antlr.org/license.html</url>
      </urls>
    </license>
    [...]
  </valid>

The result of the above change is the following output:

[INFO]
[INFO] --- maven-license-verifier-plugin:0.4:verify (license-verifier) @ sapm ---
[INFO] Loading /home/kama/ws-git/sapm/src/licenses/licenses.xml licenses file.
[WARNING] ]UNKNOWN[ (compile) The artifact org.antlr:antlr-runtime:jar:3.3 has a license which is categorized as unknown
[WARNING] ]UNKNOWN[ (compile) The artifact org.antlr:stringtemplate:jar:3.2.1 has a license which is categorized as unknown
[WARNING] ]UNKNOWN[ (test) The artifact org.beanshell:bsh:jar:2.0b4 has a license which is categorized as unknown
[INFO]
[INFO] --- maven-jar-plugin:2.3.1:jar (default-jar) @ sapm ---
[INFO] Building jar: /home/kama/ws-git/sapm/target/sapm-0.5-SNAPSHOT.jar
[INFO]
[INFO] --- maven-site-plugin:3.0-beta-3:attach-descriptor (attach-descriptor) @ sapm ---
[INFO] Parent project loaded from repository.
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 13.933s
[INFO] Finished at: Sat Apr 30 17:08:20 CEST 2011
[INFO] Final Memory: 21M/257M
[INFO] ------------------------------------------------------------------------

This will just remove only a single warning in this case for the antlr:antlr:jar:2.7.7 artifact. To get rid of the warnings for the other artifacts we have to added appropriate entries in to the licenses.xml files as well.

If you take a look at the org.antlr:antlr-runtime:jar:3.3 artifact you will find out that this artifact itself does not have a license entry nor its parent has one. This means this artifact does not contain a licens eat all. In this case you have to exclude this artifact from being checked which simply means to enhance the configuration section of the plugin like the following:

  <plugin>
    <groupId>com.soebes.maven.plugins.mlv</groupId>
    <artifactId>maven-license-verifier-plugin</artifactId>
    <version>0.4</version>
    <executions>
      <execution>
        <id>license-verifier</id>
        <goals>
          <goal>verify</goal>
        </goals>
        <configuration>
          <excludes>
            <exclude>org.antlr:antlr-runtime:jar:3.3</exclude>
          </excludes>
        </configuration>
      </execution>
    </exectuions>
  </plugin>

After changing the configuration the output of a mvn clean package looks like this:

[INFO]
[INFO] --- maven-license-verifier-plugin:0.4:verify (license-verifier) @ sapm ---
[INFO] Loading /home/kama/ws-git/sapm/src/licenses/licenses.xml licenses file.
[WARNING] ]UNKNOWN[ (compile) The artifact org.antlr:stringtemplate:jar:3.2.1 has a license which is categorized as unknown
[WARNING] ]UNKNOWN[ (test) The artifact org.beanshell:bsh:jar:2.0b4 has a license which is categorized as unknown
[INFO]

So we have to continue and check the artifact org.antlr:stringtemplate:jar:3.2.1. This artifact has a BSD License as well, but why hasn't it been categorized as being valid? The simple answer is: It has a different URL http://antlr.org/license.html instead of http://www.antlr.org/license.html. So we have to add the other URL into the licenses.xml.

  <valid>
    [...]
    <license>
      <id>BSD License</id>
      <description>BSD License</description>
      <names>
        <name>BSD License</name>
      </names>
      <urls>
        <url>http://www.antlr.org/license.html</url>
        <url>http://antlr.org/license.html</url>
      </urls>
    </license>
    [...]
  </valid>

After this change the output looks now like the following:

[INFO]
[INFO] --- maven-license-verifier-plugin:0.3-SNAPSHOT:verify (license-verifier) @ sapm ---
[INFO] Loading /home/kama/ws-git/sapm/src/licenses/licenses.xml licenses file.
[WARNING] ]UNKNOWN[ (test) The artifact org.beanshell:bsh:jar:2.0b4 has a license which is categorized as unknown
[INFO]

The final artifact itself does not contain the license only it's parent contains the license which it this case is (excerpt from the parents pom.xml).

 <licenses>
    <license>
      <name>GNU LESSER GENERAL PUBLIC LICENSE</name>
      <url>http://www.gnu.org/licenses/lgpl.txt</url>
    </license>
  </licenses>

Now finally we have to add this license to our licenses.xml file.

  <valid>
    [...]
    <license>
      <id>GNU LESSER GENERAL PUBLIC LICENSE</id>
      <description>GNU LESSER GENERAL PUBLIC LICENSE</description>
      <names>
       <name>GNU LESSER GENERAL PUBLIC LICENSE</name>
      </names>
      <urls>
        <url>http://www.gnu.org/licenses/lglp.txt</url>
      </urls>
    </license>
    [...]
 </valid>

And now finally the output of the mvn clean package looks like this:

[INFO]
[INFO] --- maven-license-verifier-plugin:0.3-SNAPSHOT:verify (license-verifier) @ sapm ---
[INFO] Loading /home/kama/ws-git/sapm/src/licenses/licenses.xml licenses file.
[INFO]