se/SE/schema/WPS_Functions/dita-ot/dita-ot-3.5/docsrc/topics/plugin-dependencies.dita

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE concept PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<!--  This file is part of the DITA Open Toolkit project. See the accompanying LICENSE file for applicable license.  -->

<concept id="plugin-dependencies" xml:lang="en-US">
  <title>Plug-in dependencies</title>
  <shortdesc>A DITA-OT plug-in can be dependent on other plug-ins. Prerequisite plug-ins are installed first, which
    ensures that DITA-OT handles XSLT overrides correctly.</shortdesc>
  <prolog>
    <metadata>
      <keywords>
        <indexterm><xmlelement>require</xmlelement></indexterm>
        <indexterm>plug-ins
          <indexterm>prerequisites</indexterm>
          <indexterm>dependencies</indexterm>
          <indexterm>order</indexterm>
          <indexterm><xmlelement>require</xmlelement></indexterm></indexterm>
        <indexterm>XSLT
          <index-see-also>plug-ins</index-see-also></indexterm>
      </keywords>
    </metadata>
  </prolog>
  <conbody>
    <draft-comment author="Kristen Eberlein" time="24 February 2016">
      <p>I'm not entirely happy with this topic as it currently is, but want to move forward with the overall
        rework.</p>
      <p>The original topic was quite a mixture of task, concept, and reference. While it could have been reworked as a
        task topic, it really was about working with a <filepath>plugin.xml</filepath> file, not using an extension
        point.</p>
      <p>I still wonder whether this topic would be better of as a reference topic in the reference section for the
        topic cluster.</p>
    </draft-comment>
    <section>
      <p>The <xmlelement>require</xmlelement> element in the <filepath>plugin.xml</filepath> file specifies whether the
        plug-in has dependencies. Use <xmlelement>require</xmlelement> elements to specify prerequisite plug-ins, in
        order from most general to most specific.</p>
      <p>If a prerequisite plug-in is missing, DITA-OT prints a warning during installation. To suppress the warning but
        keep the installation order if both plug-ins are present, add <codeph>importance="optional"</codeph> to the
          <xmlelement>require</xmlelement> element. </p>
      <!--<p>If the current plug-in requires a plug-in with <codeph>id="plugin-id"</codeph> before it can be installed, it would include the following: </p><codeblock>&lt;require plugin="<i>plugin-id</i>"></codeblock>-->
      <p>If a plug-in can depend on any one of several optional plug-ins, separate the plug-in IDs with a vertical bar.
        This is most useful when combined with <codeph>importance="optional"</codeph>.</p>
    </section>
    <example>
      <title>Example: Plug-in with a prerequisite plug-in</title>
      <p>The following plug-in will only be installed if the plug-in with the ID <codeph>com.example.primary</codeph> is
        available. If that plug-in is not available, a warning is generated and the installation operation fails.</p>
      <codeblock outputclass="language-xml normalize-space show-line-numbers show-whitespace">&lt;plugin id="com.example.builds-on-primary">
  &lt;!-- ... Extensions here -->
  &lt;require plugin="com.example.primary"/>
&lt;/plugin></codeblock>
    </example>
    <example>
      <title>Example: Plug-in that has optional plug-ins</title>
      <p>The following plug-in will only be installed if either the plug-in with the ID <codeph>pluginA</codeph> or the
        plug-in with the ID <codeph>pluginB</codeph> is available. If neither of those plug-ins are installed, a warning
        is generated but the installation operation is completed.</p>
      <codeblock outputclass="language-xml normalize-space show-line-numbers show-whitespace">&lt;plugin id="pluginC">
  &lt;!-- ...extensions here -->
  &lt;require plugin="pluginA|pluginB" importance="optional"/>
&lt;/plugin></codeblock>
      <draft-comment author="Kristen Eberlein" time="24 February 2016">
        <p>We need to check this example against the toolkit. Text in the original topic was wrong, but I have not
          tested this.</p>
      </draft-comment>
    </example>
  </conbody>
</concept>