PandocRuby

PandocRuby is a wrapper for Pandoc, a Haskell library with command line tools for converting one markup format to another.

Pandoc can convert documents from a variety of formats including markdown, reStructuredText, textile, HTML, DocBook, LaTeX, and MediaWiki markup to a variety of other formats, including markdown, reStructuredText, HTML, LaTeX, ConTeXt, PDF, RTF, DocBook XML, OpenDocument XML, ODT, GNU Texinfo, MediaWiki markup, groff man pages, HTML slide shows, EPUB, Microsoft Word docx, and more.

First, install Pandoc.

PandocRuby is available on RubyGems:

gem install pandoc-ruby

To install with Bundler, add the following to your Gemfile:

gem 'pandoc-ruby'

Then run bundle install

require 'pandoc-ruby'
@converter = PandocRuby.new('# Markdown Title', from: :markdown, to: :rst)
puts @converter.convert

This takes the Markdown formatted string and converts it to reStructuredText.

You can also use the #convert class method:

puts PandocRuby.convert('# Markdown Title', from: :markdown, to: :html)

Other arguments are simply converted into command line options, accepting symbols and strings for options and hashes for options with arguments.

PandocRuby.convert('# Markdown Title', :s, {f: :markdown, to: :rst}, '--wrap=none', :table_of_contents)

is equivalent to

echo "# Markdown Title" | pandoc -s -f markdown --to=rst --wrap=none --table-of-contents

Also provided are #to_[writer] instance methods for each of the writers, and these can also accept options:

PandocRuby.new('# Example').to_html(:ascii)
# => "<h1 id="example">Example</h1>"
# or
PandocRuby.new("# Example").to_rst
# => "Example
#     ======="

Similarly, there are class methods for each of the readers, so readers and writers can be specified like this:

PandocRuby.html("<h1>hello</h1>").to_latex
# => "\\section{hello}"

Available readers and writers are can be found in the following variables:

• PandocRuby::READERS
• PandocRuby::STRING_WRITERS
• PandocRuby::BINARY_WRITERS
• PandocRuby::WRITERS

PandocRuby assumes the pandoc executable is in your environment's $PATH variable. If you'd like to set an explicit path to the pandoc executable, you can do so with PandocRuby.pandoc_path = '/path/to/pandoc'

PandocRuby can also take an array of one or more file paths as the first argument. The files will be concatenated together with a blank line between each and used as input.

# One file path as a single-element array.
PandocRuby.new(['/path/to/file1.docx'], from: 'docx').to_html
# Multiple file paths as an array.
PandocRuby.new(['/path/to/file1.docx', '/path/to/file1.docx'], from: 'docx').to_html

If you are trying to generate a standalone file with full file headers rather than just a marked up fragment, remember to pass the :standalone option so the correct header and footer are added.

PandocRuby.new("# Some title", :standalone).to_rtf

Pandoc extensions can be used to modify the behavior of readers and writers. To use an extension, add the extension with a + or - after the reader or writer name:

# Without extension:
PandocRuby.new("Line 1\n# Heading", from: 'markdown_strict').to_html
# => "<p>Line 1</p>\n<h1>Heading</h1>\n"

# With `+blank_before_header` extension:
PandocRuby.new("Line 1\n# Heading", from: 'markdown_strict+blank_before_header').to_html
# => "<p>Line 1 # Heading</p>\n

For more information on Pandoc, see the Pandoc documentation or run man pandoc (also available here).

If you'd prefer a pure-Ruby extended markdown interpreter that can output a few different formats, take a look at kramdown. If you want to use the full reStructuredText syntax from within Ruby, check out RbST, a docutils wrapper.

This gem was inspired by Albino. For a slightly different approach to using Pandoc with Ruby, see Pandoku.

• Fork the project.
• Make your feature addition or bug fix.
• Add tests for it. This is important so I don't break it in a future version unintentionally.
• Commit, do not mess with rakefile, version, or history. (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
• Send me a pull request. Bonus points for topic branches.