Allow overriding reader extensions.

This adds an extensions setting all readers in the style of [ext]_EXTENSIONS. So for the MarkdownReader, who's extension is "md", the setting read is MD_EXTENSIONS.

The settings allow overriding the default options passed through the readers. In the case of Markdown the default values are ['codehilite','extra'], but user may change this through the setting:

MD_EXTENSIONS = ['footnotes','abbr','codehilite']

docs/settings.rst

@@ -46,6 +46,10 @@ Setting name (default value)                        what does it do?
 `MARKUP` (``('rst', 'md')``)                        A list of available markup languages you want
                                                     to use. For the moment, only available values
                                                     are `rst` and `md`.
+`MD_EXTENSIONS` (``('codehilite','extra')``)        A list of the extensions that the markdown processor
+                                                    will use. Refer to the extensions chapter in the
+                                                    Python-Markdown documentation for a complete list of
+                                                    supported extensions.
 `OUTPUT_PATH` (``'output/'``)                       Where to output the generated files.
 `PATH` (``None``)                                   path to look at for input files.
 `PDF_GENERATOR` (``False``)                         Set to True if you want to have PDF versions

pelican/generators.py

@@ -211,7 +211,7 @@ class ArticlesGenerator(Generator):
         files = self.get_files(self.path, exclude=['pages',])
         all_articles = []
         for f in files:
-            content, metadata = read_file(f)
+            content, metadata = read_file(f, settings=self.settings)
 
             # if no category is set, use the name of the path as a category
             if 'category' not in metadata.keys():

pelican/readers.py

@@ -32,7 +32,7 @@ def _process_metadata(name, value):
 
 class Reader(object):
     enabled = True
-
+    extensions = None
 
 class _FieldBodyTranslator(HTMLTranslator):
 
@@ -99,11 +99,12 @@ class RstReader(Reader):
 class MarkdownReader(Reader):
     enabled = bool(Markdown)
     extension = "md"
+    extensions = ['codehilite', 'extra']
 
     def read(self, filename):
         """Parse content and metadata of markdown files"""
         text = open(filename)
-        md = Markdown(extensions = ['meta', 'codehilite', 'extra'])
+        md = Markdown(extensions=set(self.extensions+['meta']))
         content = md.convert(text)
 
         metadata = {}
@@ -133,13 +134,16 @@ class HtmlReader(Reader):
 
 _EXTENSIONS = dict((cls.extension, cls) for cls in Reader.__subclasses__())
 
-def read_file(filename, fmt=None):
+def read_file(filename, fmt=None, settings=None):
     """Return a reader object using the given format."""
     if not fmt:
         fmt = filename.split('.')[-1]
     if fmt not in _EXTENSIONS.keys():
         raise TypeError('Pelican does not know how to parse %s' % filename)
     reader = _EXTENSIONS[fmt]()
+    settings_key = '%s_EXTENSIONS' % fmt.upper()
+    if settings and settings_key in settings:
+        reader.extensions = settings[settings_key]
     if not reader.enabled:
         raise ValueError("Missing dependencies for %s" % fmt)
     return reader.read(filename)