PlantUML Extension for Python-Markdown

This plugin implements a block extension which can be used to specify a PlantUML diagram which will be converted into an image and inserted in the document.

Syntax:

    ::uml:: [format="png|svg|txt"] [classes="class1 class2 ..."] [alt="text for alt"] [title="Text for title"] ]width="300px"] [height="300px"]
      PlantUML script diagram
    ::end-uml::

Example:

    ::uml:: format="png" classes="uml myDiagram" alt="My super diagram placeholder" title="My super diagram" width="300px" height="300px"
      Goofy ->  MickeyMouse: calls
      Goofy <-- MickeyMouse: responds
    ::end-uml::

The GitLab/GitHub block syntax is also recognized. Example:

```plantuml format="png" classes="uml myDiagram" alt="My super diagram placeholder" title="My super diagram" width="300px" height="300px"
  Goofy ->  MickeyMouse: calls
  Goofy <-- MickeyMouse: responds
```

Options are optional (otherwise the wouldn't be options), but if present must be specified in the order format, classes, alt, title, width, height. The option value may be enclosed in single or double quotes.

Supported values for format parameter are:

• png: HTML img tag with embedded png image
• svg: HTML img tag with embedded svg image (links are not navigable)
• svg_object: HTML object tag with embedded svg image (links are navigable)
• svg_inline: HTML5 svg tag with inline svg image source (links are navigable, can be manipulated with CSS rules)
• txt: plain text diagrams.

The width and height options must include a CSS unit.

Installation

You need to install PlantUML (see the site for details) and Graphviz 2.26.3 or later. The plugin expects a program plantuml in the classpath. If not installed by your package manager, you can create a shell script and place it somewhere in the classpath. For example, save te following into /usr/local/bin/plantuml (supposing PlantUML installed into /opt/plantuml):

    #!/bin/bash
    java -jar /opt/plantuml/plantuml.jar ${@}

On Windows can be used the following plantuml.bat (many thanks to henn1001):

    @echo off
    set mypath=%~dp0
    
    setlocal
    set GRAPHVIZ_DOT=%mypath%\Graphviz\bin\dot.exe

    java -jar %mypath%\plantuml.jar %*

Make sure the plantuml.bat is on the path.

For Gentoo Linux there is an ebuild at http://gpo.zugaina.org/dev-util/plantuml/RDep: you can download the ebuild and the files subfolder or you can add the zugaina repository with layman (recommended).

To use the plugin with Python-Markdown you have three choices:

• do a simple pip install plantuml-markdown, and the plugin should be ready to be used

• copy the file plantuml.py in the extensions folder of Python-Markdown. For example, for Python 2.7 you must do:

  $ sudo cp plantuml.py /usr/lib/python27/site-packages/markdown/extensions/

• copy the file somewhere in your home. A good choice may be the user-site path, for example (bash syntax):

  $ export INSTALLPATH="`python -m site --user-site`/plantuml-markdown"
  $ mkdir -p "$INSTALLPATH"
  $ cp plantuml.py "$INSTALLPATH/mdx_plantuml.py"
  $ export PYTHONPATH="$INSTALLPATH"

  You must export PYTHONPATH before running markdown_py, or you can put the definition in ~/.bashrc.

After installed, you can use this plugin by activating it in the markdown_py command. For example:

markdown_py -x plantuml mydoc.md > out.html

Running tests

The test execution requires a specific version of PlantUML (the image generated can be different with different PlantUML versions).

To run the tests, execute the following command:

PATH="$PATH:$PWD/test" python -m unittest discover -v -s test

This command uses a custom version of the plantuml command which will download the expected version of PlantUML for tests execution without clobbering the system.