1 """

     2 Set of "markup" template filters for Django.  These filters transform plain text

     3 markup syntaxes to HTML; currently there is support for:

     4 

     5     * Textile, which requires the PyTextile library available at

     6       http://dealmeida.net/projects/textile/

     7 

     8     * Markdown, which requires the Python-markdown library from

     9       http://www.freewisdom.org/projects/python-markdown

    10 

    11     * ReStructuredText, which requires docutils from http://docutils.sf.net/

    12 

    13 In each case, if the required library is not installed, the filter will

    14 silently fail and return the un-marked-up text.

    15 """

    16 

    17 from django import template

    18 from django.conf import settings

    19 from django.utils.encoding import smart_str, force_unicode

    20 from django.utils.safestring import mark_safe

    21 

    22 register = template.Library()

    23 

    24 def textile(value):

    25     try:

    26         import textile

    27     except ImportError:

    28         if settings.DEBUG:

    29             raise template.TemplateSyntaxError, "Error in {% textile %} filter: The Python textile library isn't installed."

    30         return force_unicode(value)

    31     else:

    32         return mark_safe(force_unicode(textile.textile(smart_str(value), encoding='utf-8', output='utf-8')))

    33 textile.is_safe = True

    34 

    35 def markdown(value, arg=''):

    36     """

    37     Runs Markdown over a given value, optionally using various

    38     extensions python-markdown supports.

    39 

    40     Syntax::

    41 

    42         {{ value|markdown:"extension1_name,extension2_name..." }}

    43 

    44     To enable safe mode, which strips raw HTML and only returns HTML

    45     generated by actual Markdown syntax, pass "safe" as the first

    46     extension in the list.

    47 

    48     If the version of Markdown in use does not support extensions,

    49     they will be silently ignored.

    50 

    51     """

    52     try:

    53         import markdown

    54     except ImportError:

    55         if settings.DEBUG:

    56             raise template.TemplateSyntaxError, "Error in {% markdown %} filter: The Python markdown library isn't installed."

    57         return force_unicode(value)

    58     else:

    59         # markdown.version was first added in 1.6b. The only version of markdown

    60         # to fully support extensions before 1.6b was the shortlived 1.6a.

    61         if hasattr(markdown, 'version'):

    62             extensions = [e for e in arg.split(",") if e]

    63             if len(extensions) > 0 and extensions[0] == "safe":

    64                 extensions = extensions[1:]

    65                 safe_mode = True

    66             else:

    67                 safe_mode = False

    68 

    69             # Unicode support only in markdown v1.7 or above. Version_info

    70             # exist only in markdown v1.6.2rc-2 or above.

    71             if getattr(markdown, "version_info", None) < (1,7):

    72                 return mark_safe(force_unicode(markdown.markdown(smart_str(value), extensions, safe_mode=safe_mode)))

    73             else:

    74                 return mark_safe(markdown.markdown(force_unicode(value), extensions, safe_mode=safe_mode))

    75         else:

    76             return mark_safe(force_unicode(markdown.markdown(smart_str(value))))

    77 markdown.is_safe = True

    78 

    79 def restructuredtext(value):

    80     try:

    81         from docutils.core import publish_parts

    82     except ImportError:

    83         if settings.DEBUG:

    84             raise template.TemplateSyntaxError, "Error in {% restructuredtext %} filter: The Python docutils library isn't installed."

    85         return force_unicode(value)

    86     else:

    87         docutils_settings = getattr(settings, "RESTRUCTUREDTEXT_FILTER_SETTINGS", {})

    88         parts = publish_parts(source=smart_str(value), writer_name="html4css1", settings_overrides=docutils_settings)

    89         return mark_safe(force_unicode(parts["fragment"]))

    90 restructuredtext.is_safe = True

    91 

    92 register.filter(textile)

    93 register.filter(markdown)

    94 register.filter(restructuredtext)