http goal

    mvn clean asciidoctor:http

This starts a small netty server + directory poller (from commons-io)

To ease the usage of such a tool (and to avoid to always use another plugin i added <synchronizations> block in existing mojo), here is a sample:

    <plugin>
        <groupId>org.asciidoctor</groupId>
        <artifactId>asciidoctor-maven-plugin</artifactId>
        <version>0.1.3-SNAPSHOT</version>
        <configuration>
          <synchronizations>
            <synchronization>
              <source>src/doc/resources</source>
              <target>target/generated/docs</target>
            </synchronization>
          </synchronizations>

          <backend>html5</backend>
          <compact>true</compact>
          <headerFooter>true</headerFooter>
          <title>Title</title>

          <attributes>
            <highlightjsdir>highlight</highlightjsdir>
            <highlightjs-theme>github</highlightjs-theme>

            <author>Romain Manni-Bucau</author>
            <email>romain.manni-bucau@mail.com</email>
            <revdate>${maven.build.timestamp}</revdate>
            <revnumber>${project.version}</revnumber>
          </attributes>
        </configuration>
      </plugin>

Then you can go on http://localhost:<port>/<name of the asciidoc file without the extension>