title: Maven custom archive extension - how do I use unpack-dependencies?
body: <p>I have a custom artfiact type <code>web-module</code>; just a ZIP but with a custom extension.</p>
  
  <p>I then have a project depending on it, I want its dependencies of this custom type to be unpacked. The <a href="http://maven.apache.org/plugins/maven-dependency-plugin" rel="noreferrer">maven-dependency-plugin</a> <a href="http://maven.apache.org/plugins/maven-dependency-plugin/unpack-dependencies-mojo.html" rel="noreferrer">unpack-dependencies</a> goal seemed to fit the bill, however I keep getting the error:</p>
  
  <pre><code>[INFO] Unknown archiver type
  Embedded error: No such archiver: 'web-module'.
  [INFO] ------------------------------------------------------------------------
  [INFO] Trace
  org.apache.maven.lifecycle.LifecycleExecutionException: Unknown archiver type
      at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoals(DefaultLifecycleExecutor.java:719)
      at org.apache.maven.lifecycle.DefaultLifecycleExecutor.executeGoalWithLifecycle(DefaultLifecycleExecutor.java:556)
      ...
  </code></pre>
  
  <p>I've done some <a href="http://maven.40175.n5.nabble.com/Problems-with-register-new-archive-type-td4574907.html" rel="noreferrer">Googling</a> and understood that I can specifiy a custom unarchiver type in my custom plugin's <em>components.xml</em>. The following is now in my <em>components.xml</em>:</p>
  
  <pre><code>&lt;component&gt;
    &lt;role&gt;org.codehaus.plexus.archiver.UnArchiver&lt;/role&gt;
    &lt;role-hint&gt;web-module&lt;/role-hint&gt;
    &lt;implementation&gt;org.codehaus.plexus.archiver.zip.ZipUnArchiver&lt;/implementation&gt;
    &lt;instantiation-strategy&gt;per-lookup&lt;/instantiation-strategy&gt;
  &lt;/component&gt;
  </code></pre>
  
  <p>Once an install of my custom plugin was performed I tried again, still no luck! Anyone know where I'm going wrong?</p>
  
  <p>I have also tried adding the custom extension plugin to the erroring module's POM with <code>&lt;extensions&gt;true&lt;/extensions&gt;</code>.</p>