Markdown

This is a Python implementation of John Gruber’s Markdown. It is almost completely compliant with the reference implementation, though there are a few very minor differences. See John’s Syntax Documentation for the syntax rules.

First and foremost, Python-Markdown is intended to be a python library module used by various projects to convert Markdown syntax into HTML.

The Basics

To use markdown as a module:

import markdown
html = markdown.markdown(your_text_string)

The Details

Python-Markdown provides two public functions (markdown() and markdownFromFile()) both of which wrap the public class Markdown. If you’re processing one document at a time, the functions will serve your needs. However, if you need to process multiple documents, it may be advantageous to create a single instance of the class:`Markdown class and pass multiple documents through it.

markdown.markdown(text[, **kwargs])

The following options are available on the markdown.markdown function:

  • text (required): The source text string.

    Note that Python-Markdown expects Unicode as input (although a simple ASCII string may work) and returns output as Unicode. Do not pass encoded strings to it! If your input is encoded, (e.g. as UTF-8), it is your responsibility to decode it. For example:

    input_file = codecs.open("some_file.txt", mode="r", encoding="utf-8")
    text = input_file.read()
    html = markdown.markdown(text)
    

    If you want to write the output to disk, you must encode it yourself:

    output_file = codecs.open("some_file.html", "w",
                            encoding="utf-8",
                            errors="xmlcharrefreplace"
                        )
    output_file.write(html)
    
  • extensions: A list of extensions.

    Python-Markdown provides an API for third parties to write extensions to the parser adding their own additions or changes to the syntax. A few commonly used extensions are shipped with the markdown library. See the [extension documentation](extensions/index.html) for a list of available extensions.

    The list of extensions may contain instances of extensions or strings of extension names. If an extension name is provided as a string, the extension must be importable as a python module either within the markdown.extensions package or on your PYTHONPATH with a name starting with mdx_, followed by the name of the extension. Thus, extensions=[‘extra’] will first look for the module markdown.extensions.extra, then a module named mdx_extra.

  • extension_configs: A dictionary of configuration settings for extensions.

    The dictionary must be of the following format:

    extension_configs = {'extension_name_1':
                   [
                      ('option_1', 'value_1'),
                      ('option_2', 'value_2')
                   ],
                 'extension_name_2':
                   [
                      ('option_1', 'value_1')
                   ]
    }
    

    See the documentation specific to the extension you are using for help in specifying configuration settings for that extension.

  • output_format: Format of output.

    Supported formats are: * “xhtml1”: Outputs XHTML 1.x. Default. * “xhtml5”: Outputs XHTML style tags of HTML 5 * “xhtml”: Outputs latest supported version of XHTML (currently XHTML 1.1). * “html4”: Outputs HTML 4 * “html5”: Outputs HTML style tags of HTML 5 * “html”: Outputs latest supported version of HTML (currently HTML 4).

    Note that it is suggested that the more specific formats (“xhtml1”, “html5”, & “html4”) be used as “xhtml” or “html” may change in the future if it makes sense at that time. The values can either be lowercase or uppercase.

  • safe_mode: Disallow raw html.

    If you are using Markdown on a web system which will transform text provided by untrusted users, you may want to use the “safe_mode” option which ensures that the user’s HTML tags are either replaced, removed or escaped. (They can still create links using Markdown syntax.)

    The following values are accepted:

    • False (Default): Raw HTML is passed through unaltered.
    • replace: Replace all HTML blocks with the text assigned to
      html_replacement_text To maintain backward compatibility, setting safe_mode=True will have the same effect as safe_mode=’replace’.

    To replace raw HTML with something other than the default, do:

    md = markdown.Markdown(safe_mode='replace',
                           html_replacement_text='--RAW HTML NOT ALLOWED--')
    
  • remove: All raw HTML will be completely stripped from the text with

    no warning to the author.

  • escape: All raw HTML will be escaped and included in the document.

    For example, the following source:

    Foo <b>bar</b>.
    

    Will result in the following HTML:

    <p>Foo &lt;b&gt;bar&lt;/b&gt;.</p>
    

    Note that “safe_mode” also alters the default value for the enable_attributes option.

  • html_replacement_text: Text used when safe_mode is set to replace. Defaults to [HTML_REMOVED].

  • tab_length: Length of tabs in the source. Default: 4

  • enable_attributes: Enable the conversion of attributes. Defaults to True, unless safe_mode is enabled, in which case the default is False.

    Note that safe_mode only overrides the default. If enable_attributes is explicitly set, the explicit value is used regardless of safe_mode. However, this could potentially allow an untrusted user to inject JavaScript into your documents.

  • smart_emphasis: Treat _connected_words_ intelligently Default: True

  • lazy_ol: Ignore number of first item of ordered lists. Default: True

    Given the following list:

    4. Apples
    5. Oranges
    6. Pears
    

    By default markdown will ignore the fact the the first line started with item number “4” and the HTML list will start with a number “1”. If lazy_ol is set to True, then markdown will output the following HTML:

    <ol>
        <li start="4">Apples</li>
        <li>Oranges</li>
        <li>Pears</li>
    </ol>
    
markdown.markdownFromFile(**kwargs)

With a few exceptions, markdownFromFile() accepts the same options as markdown(). It does not accept a text (or Unicode) string. Instead, it accepts the following required options:

  • input (required): The source text file.

    input may be set to one of three options:

    • a string which contains a path to a readable file on the file system,
    • a readable file-like object,
    • or None (default) which will read from stdin.
  • output: The target which output is written to.

    output may be set to one of three options:

    • a string which contains a path to a writable file on the file system,
    • a writable file-like object,
    • or None (default) which will write to stdout.
  • encoding: The encoding of the source text file. Defaults

    to “utf-8”. The same encoding will always be used for input and output. The ‘xmlcharrefreplace’ error handler is used when encoding the output.

    Note: This is the only place that decoding and encoding of unicode takes place in Python-Markdown. If this rather naive solution does not meet your specific needs, it is suggested that you write your own code to handle your encoding/decoding needs.

class markdown.Markdown([**kwargs])

The same options are available when initializing the Markdown class as on the markdown() function, except that the class does not accept a source text string on initialization. Rather, the source text string must be passed to one of two instance methods:

Markdown.convert(source)

The source text must meet the same requirements as the text argument of the markdown() function.

You should also use this method if you want to process multiple strings without creating a new instance of the class for each string.:

md = markdown.Markdown()
html1 = md.convert(text1)
html2 = md.convert(text2)

Note that depending on which options and/or extensions are being used, the parser may need its state reset between each call to convert.:

html1 = md.convert(text1)
md.reset()
html2 = md.convert(text2)

You can also change calls to reset together:

html3 = md.reset().convert(text3)
Markdown.convertFile(**kwargs)

The arguments of this method are identical to the arguments of the same name on the markdownFromFile() function (input, output, and encoding). As with the convert() method, this method should be used to process multiple files without creating a new instance of the class for each document. State may need to be reset between each call to convertFile() as is the case with convert().