# Publishing Argdown-Markdown with Pandoc

Pandoc is a popular "document converter" that can be used to export Markdown files into pdf, latex, html or many other formats.

You can add Argdown support to Pandoc by installing the @argdown/pandoc-filter. This will create a powerful tool for publishing argument maps in pdf documents or html pages.

The filter can export your argument maps as svg, png, jpg or webp images and has many configuration options.

# Installation

The Pandoc installation process is less complex than it might look and is definitely worth it, so let's get started:

  1. Install Pandoc
  2. Install LaTeX and rsvg-convert (both will be needed by Pandoc).
  3. If you have not already done so, install node and npm.

Next, let's add Argdown support by installing the @argdown/pandoc-filter:

npm install -g @argdown/pandoc-filter

If you want to convert your argument maps to pixel images (instead of svgs), install @argdown/image-export with:

npm install -g @argdown/image-export

TIP

If you run this on Linux, check out the plugin's README for how to install additional dependencies.

The pandoc filter will automatically look for the image export plugin on your computer and use it as needed.

If you want to add Argdown syntax highlighting to Pandoc, download the files from Sebastian Cacean's nice argdown-pandoc-highlighting and use them according to the instructions there. Alternatively you can also use the web-component export for this purpose as explained further below.

# Exporting Argdown-Markdown to PDF or HTML

Let's say we have a Argdown-Markdown file called input-file.md with the following content:

This is _Markdown_ code. Here comes an _Argdown_ code block:

```argdown-map
[s1]: text
    <- <a1>: text
```

To export input-file.md to a PDF document named output-file.pdf, run the following command on OSX or Linux:

pandoc input-file.md -f markdown -t pdf --filter argdown-filter -o output-file.pdf

On Windows 10 you have to use argdown-filter.cmd instead:

pandoc input-file.md -f markdown -t pdf --filter argdown-filter.cmd -o output-file.pdf

On Windows 8.1 using node filters this way currently does not work (see here and here).

To export input-file.md to a HTML document named output-file.html, run the following command on OSX or Linux:

pandoc input-file.md -f markdown -t html -s --filter argdown-filter -o output-file.html

On Windows use --filter argdown-filter.cmd.

Consult the Pandoc documentation for further information on the general use of Pandoc.

# Configuring the Argdown filter

By default the Argdown filter will export argdown-map code blocks as svg inline images that will not be saved separately from the exported main document.

Here is how to export argdown-map code blocks as external png image files instead (will only work if you have installed @argdown/image-export):

---
argdown:
  mode: "file"
  format: "png"
---

This is _Markdown_ code. Here comes an _Argdown_ code block:

```argdown-map
[s1]: text
    <- <a1>: text
```

We are using a Markdown YAML metadata section to configure the Argdown filter, setting the mode and format properties. The configuration will be applied to all exports of argdown-map code blocks.

You can also add different configurations for different code blocks by using the following syntax:

Here comes the first one:

```{.argdown #fig:first-map caption="First map"}
[s1]
    <- <a1>
```

And here is the second one:

```{.argdown #fig:second-map caption="Second map"}
[s1]
    <- <a1>
```

And here we refer to @fig:first-map and @fig:second-map in Markdown.

Here we are defining figure captions and ids for the two maps. Using pandoc-crossfref we can then later refer to these figures elsewhere in the document (as shown above).

Using the {.argdown-map configOption=configValue} syntax, all configuration options of the Argdown filter can be applied separately for each argdown-map code block.

WARNING

The downside of using code block meta data is that the VSCode Markdown preview does not recognize this pandoc-specific format and Argdown code blocks will not be transformed to web-components.

# Using argdown.config.json files

Here is how you can instruct the Argdown filter to use a argdown.config.json file for further configuration of the Argdown parser:

---
argdown:
  config: "some-folder/argdown.config.json"
  mode: "web-component"
---

```argdown-map
===
webComponent:
    withoutHeader: true
===

[s1]
    <- <a1>
```

You can also use a different config file for specific code blocks:

```{.argdown-map config="some-other-folder/some-other-name.config.json"}
[s1]
    <+ <a2>
```

In this example the first Argdown code block will be exported using the Argdown config file defined in the Markdown metadata and the additional configuration defined in the YAML frontmatter section of the code block.

The second code block will be exported by using the second config file defined in the code block's meta data.

WARNING

Note that in this example the file paths are relative to the directory where you run pandoc (the "current working directory"), so be careful to always run it from the same directory or the config files will not be found.

# Export modes and formats

Use the mode configuration property to choose one of the following export modes:

  • inline: inline image (default)
  • file: external image
  • web-component: web-component html (only recommended if you export to html)

Use the format configuration property to choose one of the following image formats (only used if the mode is not web-component):

  • svg
  • png
  • jpg
  • webp

The latter three are only supported if you install the @argdown/image-export plugin (see installation instructions).

If you use the file mode, the Argdown parser will automatically name the exported image files (either by calling them map-1, map-2, ... or by using the figure id defined with #fig:some-id).

# Image width and height

You can set the image width and height in the code block's metadata:

```{.argdown-map width=800}
[s1]
    <- <a1>
```

# Highlighting the syntax in argdown code blocks

By default argdown code blocks are ignored by the Argdown filter. Only argdown-map code blocks are exported. This makes it possible to use the official Pandoc syntax highlighting (see argdown-pandoc-highlighting) for argdown code blocks.

If you want to use the Argdown filter for this purpose, you can export argdown code blocks as web-component html, using its "source view" for syntax highlighting. This makes sense if you want to export to HTML and already use the web-component for argdown-map code blocks.

Here is how you use the web-component to highlight argdown code blocks:

---
argdown:
  sourceHighlighter: web-component
---

```argdown
===
webComponent:
    withoutHeader: true
    views:
        source: true
        map: false
===

[s1]
    <- <a1>
```

In this example we are also configuring the web-component export in the YAML frontmatter section so that the web-component is exported without the map view and without the header (containing logo and buttons). Of course you could also add this configuration to an argdown.config.json file and use the config option to point to this file (see above).