Moved base Extension class and extension loaders to markdown/extensions/__init__.py. Now only the Markdown class and two public wrappers are in markdown/__init__.py.

1 files changed, 99 insertions, 0 deletions

diff --git a/markdown/extensions/__init__.py b/markdown/extensions/__init__.py
index e69de29..1964bfc 100644
--- a/markdown/extensions/__init__.py
+++ b/markdown/extensions/__init__.py
@@ -0,0 +1,99 @@
+
+"""
+Extensions
+-----------------------------------------------------------------------------
+"""
+
+class Extension:
+    """ Base class for extensions to subclass. """
+    def __init__(self, configs = {}):
+        """Create an instance of an Extention.
+
+        Keyword arguments:
+
+        * configs: A dict of configuration setting used by an Extension.
+        """
+        self.config = configs
+
+    def getConfig(self, key):
+        """ Return a setting for the given key or an empty string. """
+        if key in self.config:
+            return self.config[key][0]
+        else:
+            return ""
+
+    def getConfigInfo(self):
+        """ Return all config settings as a list of tuples. """
+        return [(key, self.config[key][1]) for key in self.config.keys()]
+
+    def setConfig(self, key, value):
+        """ Set a config setting for `key` with the given `value`. """
+        self.config[key][0] = value
+
+    def extendMarkdown(self, md, md_globals):
+        """
+        Add the various proccesors and patterns to the Markdown Instance.
+
+        This method must be overriden by every extension.
+
+        Keyword arguments:
+
+        * md: The Markdown instance.
+
+        * md_globals: Global variables in the markdown module namespace.
+
+        """
+        raise NotImplementedError, 'Extension "%s.%s" must define an "extendMarkdown"' \
+            'method.' % (self.__class__.__module__, self.__class__.__name__)
+
+
+def load_extension(ext_name, configs = []):
+    """Load extension by name, then return the module.
+
+    The extension name may contain arguments as part of the string in the
+    following format: "extname(key1=value1,key2=value2)"
+
+    """
+
+    # Parse extensions config params (ignore the order)
+    configs = dict(configs)
+    pos = ext_name.find("(") # find the first "("
+    if pos > 0:
+        ext_args = ext_name[pos+1:-1]
+        ext_name = ext_name[:pos]
+        pairs = [x.split("=") for x in ext_args.split(",")]
+        configs.update([(x.strip(), y.strip()) for (x, y) in pairs])
+
+    # Setup the module names
+    ext_module = 'markdown.extensions'
+    module_name_new_style = '.'.join([ext_module, ext_name])
+    module_name_old_style = '_'.join(['mdx', ext_name])
+
+    # Try loading the extention first from one place, then another
+    try: # New style (markdown.extensons.<extension>)
+        module = __import__(module_name_new_style, {}, {}, [ext_module])
+    except ImportError:
+        try: # Old style (mdx.<extension>)
+            module = __import__(module_name_old_style)
+        except ImportError:
+           message(WARN, "Failed loading extension '%s' from '%s' or '%s'"
+               % (ext_name, module_name_new_style, module_name_old_style))
+           # Return None so we don't try to initiate none-existant extension
+           return None
+
+    # If the module is loaded successfully, we expect it to define a
+    # function called makeExtension()
+    try:
+        return module.makeExtension(configs.items())
+    except AttributeError, e:
+        message(CRITICAL, "Failed to initiate extension '%s': %s" % (ext_name, e))
+
+
+def load_extensions(ext_names):
+    """Loads multiple extensions"""
+    extensions = []
+    for ext_name in ext_names:
+        extension = load_extension(ext_name)
+        if extension:
+            extensions.append(extension)
+    return extensions