http: HTML live preview

Converts Asciidoc documents and starts an embedded http server to access content from the generated output directory.

Modified sources will be updated on change similarly to how the auto-refresh goal works. While at the same time, HTML contents will be automatically refreshed on the web browser without need for manual steps. Just open the file through the provided url that will appear in the console and write.

While the http goal can be used to serve any kind of content (e.g. PDF). The possibilities have not been explored and are not officially supported, but feedback is welcome if you want to share your experience and ideas.

Setup

The file extension is not necessary for html files in the url. For example, the document manual.html placed in the root path will be accessible as simply http://localhost:2000/manual.

As this is a typical Maven plugin, simply declare the plugin in the <plugins> section of your POM file:

Plugin declaration in pom.xml
<plugins>
    <plugin>
        <groupId>org.asciidoctor</groupId>
        <artifactId>asciidoctor-maven-plugin</artifactId>
        <version>2.2.1</version>
        <dependency> (1)
            <groupId>org.asciidoctor</groupId>
            <artifactId>asciidoctorj</artifactId>
            <version>${asciidoctorj.version}</version>
        </dependency>
        ...
    </plugin>
</plugins>
1 The plugin will use the latest Asciidoctorj version available at release. To change it, set the desired version as a plugin dependency.
Goal setup
<plugin>
    ...
    <executions>
        <execution>
            <id>output-html</id>              (1)
            <phase>generate-resources</phase> (2)
            <goals>
                <goal>http</goal>             (3)
            </goals>
            <configuration>                   (4)
                <port>8080</port>
            </configuration>
        </execution>
    </executions>
</plugin>
1 This is simply a unique id for the execution.
2 The asciidoctor-maven-plugin does not run in any phase by default, so one must be specified.
3 The Asciidoctor Maven plugin conversion goal.
4 Maven plugin additional parameters. Here we change the port to 8080.

This goal shares the following features (and limitations) with auto-refresh.

  • Once started, the maven process will keep running until explicitly stopped (exit, quit commands or ctrl+c).

  • Deleted or moved files will remain the in output directory until a clean is run.

  • To take full advantage of all configuration options, the goal must be explicitly configured in the pom.xml (see setup note).

  • When a failIf condition occurs the goal will fail to complete and the server won’t start. But once started successfully these won’t stop the server.

Configuration

This goal inherits the same parameters as process-asciidoc and auto-refresh goals and adds:

port

server port. Defaults to 2000.

home

default resource to open when no url is indicated, that is when browsing to localhost:2000. Defaults to index.

Inherited options

sourceDirectory

path where source files are located. By default checks for ${basedir}/src/docs/asciidoc, ${basedir}/src/asciidoc or ${basedir}/src/main/asciidoc in that order. When a custom value is set, no other paths are checked.

All paths and AsciiDoc documents that start with _ are considered internal and are skipped. That is, AsciiDocs are not converted and resources are not copied from them, but you can include them normally from other AsciiDocs.
This is useful to split your sources in sets of main documents and included parts.

sourceDocumentName

an override to process a single source file; defaults to all files in ${sourceDirectory}.

sourceDocumentExtensions

(named extensions in v1.5.3 and below) a List<String> of non-standard file extensions to convert. Currently, ad, adoc, and asciidoc will be converted by default

resources

list of resource files to copy to the output directory (e.g., images, css). The configuration follows the same patterns as the maven-resources-plugin. If not set, all resources inside ${sourceDirectory} are copied.

Converters that embed resources such as images into the output document need to be able to locate those resources at conversion time. For example, when generating a PDF (or HTML with the data-uri attribute set), all images need to be aggregated under a common root (i.e., image catalog). The imagesdir attribute should be overridden to point to that folder. When converting to HTML, images must be copied to the output location so that the browser can resolve those images when the user views the page.

<resources>
    <resource>
        <!-- (Mandatory) Directory to copy from. Paths are relative to maven's ${baseDir} -->
        <directory>DIRECTORY</directory>
        <!-- (Optional) Directory to copy to. By default uses the option `outputDirectory` -->
        <targetPath>OUTPUT_DIR</targetPath>
        <!-- (Optional) NOTE: SVN, GIT and other version control files are excluded by default, there's no need to add them -->
        <excludes>
            <exclude>**/.txt</exclude>
        </excludes>
        <!-- (Optional) If not set, includes all files but default exceptions mentioned -->
        <includes>
            <include>**/*.jpg</include>
            <include>**/*.gif</include>
        </includes>
    </resource>
    ...
</resources>
outputDirectory

locations where converted sources and copied resources will be places. Note that relative paths are added to the project root path. Defaults to ${project.build.directory}/generated-docs.

outputFile

defaults to null, used to override the name of the generated output file, can be a relative or absolute path. Useful for backends that create a single file, e.g. the pdf backend. All output will be redirected to the same file, the same way as the -o, --out-file=OUT_FILE option from the asciidoctor CLI command.

baseDir

(not Maven’s basedir) enables to set the root path for resources (e.g. included files), defaults to ${sourceDirectory}

skip

set this to true to bypass generation, defaults to false

preserveDirectories

enables to specify whether the documents should be converted in the same folder structure as in the source directory or not, defaults to false. When true, instead of generating all output in a single folder, output files are generated in the same structure. See the following example

    ├── docs                          ├── docs
    │   ├── examples.adoc             │   ├── examples.html
    │   └── examples            =>    │   └── examples
    │       ├── html.adoc             │       ├── html.html
    │       └── docbook.adoc          │       └── docbook.html
    └── index.adoc                    └── index.html
relativeBaseDir

only used when baseDir is not set, enables to specify that each AsciiDoc file must search for its resources in the same folder (for example, included files). Internally, for each AsciiDoc source, sets baseDir to the same path as the source file. Defaults to false

backend

defaults to html5

doctype

defaults to null (which trigger’s Asciidoctor’s default of article)

eruby

defaults to erb, the version used in JRuby

headerFooter

defaults to true

templateDirs

list of directories of compatible templates to be used instead of the default built-in templates, empty by default.

templateEngine

template engine to use for the custom converter templates, disabled by default (null)

templateCache

enables the built-in cache used by the template converter when reading the source of template files. Only relevant if the :template_dirs option is specified, defaults to true.

sourcemap

adds file and line number information to each parsed block (lineno and source_location attributes), defaults to false

catalogAssets

tells the parser to capture images and links in the reference table available via the references property on the document AST object (experimental), defaults to false

attributes

a Map<String,Object> of Asciidoctor attributes to pass for conversion, defaults to null. Refer to the catalog of document attributes in the Asciidoctor user manual for a complete list.

example
<attributes>
    <toc>left</toc>
    <icons>font</icons>
    <imagesdir>images</imagesdir>
    <source-highlighter>coderay</source-highlighter>
</attributes>

In addition to attributes set in this section, Maven properties are also passed as attribute (replacing . by - in the name). These include those defined in the <properties> section of the project, parent projects and the user’s settings.xml.

<properties>
  <my-site.version>2.3.0</my-site.version> (1)
</properties>
1 Will be passed as my-site-version to the converter.

Note that when defining a build with multiple executions, shared attributes can be set in the global <configuration> section of the plugin.

Boolean attributes only require to be enabled or set. These, can be set with a empty tag or a boolean value. To unset an attribute, use value false.

<embedded/>
<sectnums>true</sectnums>
<linkcss>false</linkcss>
embedAssets

embeds the CSS file and images into the output, defaults to false

gemPaths

enables to specify the location to one or more gem installation directories (same as GEM_PATH environment var), empty by default

requires

a List<String> to specify additional Ruby libraries not packaged in AsciidoctorJ, empty by default

extensions

List of extensions to include during the conversion process (see AsciidoctorJ’s Extension API for information about the available options). For each extension, the implementation class must be specified in the className parameter, the blockName is only required when configuring a BlockProcessor, BlockMacroProcessor or InlineMacroProcessor.

extensions configuration example
<plugin>
    ...
    <executions>
        <execution>
            <configuration>
                ...
                <extensions>
                    <extension>
                        <className>org.asciidoctor.maven.SomePreprocessor</className>
                    </extension>
                    <extension>
                        <className>org.asciidoctor.maven.SomeBlockProcessor</className>
                        <blockName>yell</blockName>
                    </extension>
                </extensions>
            </configuration>
        </execution>
    </executions>
    <dependencies>
        <dependency> (1)
            <groupId>org.asciidoctor.maven</groupId>
            <artifactId>my-asciidoctor-extensions</artifactId>
            <version>1.0.0</version>
        </dependency>
    </dependencies>
</plugin>
1 Extensions must be included in the plugin’s execution classpath, not in the project’s.
Extensions can also be integrated through the SPI interface implementation. This method does not require any configuration in the pom.xml, see Automatically loading extensions for details.
enableVerbose

enables Asciidoctor verbose messages, defaults to false. Enable it, for example, if you want to validate internal cross references and capture the messages with the logHandler option.

logHandler

enables processing options for Asciidoctor messages (e.g. errors on missing included files), to either hide messages or setup build fail conditions based on them. Options are:

  • outputToConsole: Boolean, defaults to true. Redirects all Asciidoctor messages to Maven’s console logger as INFO during conversion.

  • failIf: build fail conditions, disabled by default. Allows setting one or many conditions that when met, abort the Maven build with BUILD FAILURE status.

    Note that the plugin matches that all conditions are met together. Unless you are controlling a very specific case, setting one condition should be enough.
    Also, messages matching fail conditions will be sent to Maven’s logger as ERROR. So, when enabling outputToConsole, some messages will appear duplicated as both INFO and ERROR.

    Currently, two conditions can be defined:

    • severity: severity of the Asciidoctor message, in order: INFO,WARN,ERROR,FATAL,UNKNOWN. Build will fail if a message is found of severity equal or higher.

    • containsText: text to search inside messages. Build will fail if the text is found.
      For example, set include to fail on any issue related to included files regardless the severity level.

      example: fail on any message
      <logHandler>
          <outputToConsole>false</outputToConsole> (1)
          <failIf>
              <severity>DEBUG</severity> (2)
          </failIf>
      </logHandler>
      1 Do not show messages as INFO in Maven output.
      2 Build will fail on any message of severity DEBUG or higher, that includes all. All matching messages will appear as ERROR in Maven output.
      Since version 1.5.8 of AsciidoctorJ set enableVerbose to true option to validate internal cross references, this is being improved to avoid false positives- See #2722 if your are interested in the details.
interval

time in milliseconds between checks of the filesystem. Defaults to 2000

refreshOn

regular expression describing additional sources that force a full refresh. Useful when working with included/partial sources that aren’t converted individually. Defaults to empty