plugins initial support

pelican/__init__.py

@@ -1,5 +1,8 @@
 import argparse
 import os
+import pkgutil
+
+from blinker import signal
 
 from pelican.generators import (ArticlesGenerator, PagesGenerator,
         StaticGenerator, PdfGenerator)
@@ -13,7 +16,7 @@ VERSION = "2.6.0"
 
 class Pelican(object):
     def __init__(self, settings=None, path=None, theme=None, output_path=None,
-            markup=None, keep=False):
+            markup=None, keep=False, plugins_path=None):
         """Read the settings, and performs some checks on the environment
         before doing anything else.
         """
@@ -41,6 +44,15 @@ class Pelican(object):
                 self.theme = theme_path
             else:
                 raise Exception("Impossible to find the theme %s" % theme)
+        
+        plugins_path = plugins_path or settings['PLUGINS_PATH']
+        if plugins_path:
+            plugins_path = os.path.abspath(plugins_path)
+            self.load_plugins(plugins_path)
+        else:
+            self.plugins = None
+        
+        signal('pelican_initialized').send(self)
 
     def run(self):
         """Run the generators and return"""
@@ -81,6 +93,13 @@ class Pelican(object):
 
     def get_writer(self):
         return Writer(self.output_path, settings=self.settings)
+    
+    def load_plugins(self,path):
+        loaded = []
+        for module_loader, name, ispkg in pkgutil.walk_packages(path=[path,]):
+            loaded.append( module_loader.find_module(name).load_module(name) )
+        self.plugins = loaded
+        
 
 
 
@@ -116,6 +135,8 @@ def main():
     parser.add_argument('-r', '--autoreload', dest='autoreload', action='store_true',
             help="Relaunch pelican each time a modification occurs on the content"
                  "files")
+    parser.add_argument('-p', '--plugins', default=None, dest='plugins_path',
+            help='the path of plugins to use')
     args = parser.parse_args()
 
     log.init(args.verbosity)
@@ -134,7 +155,7 @@ def main():
         cls = getattr(module, cls_name)
 
     try:
-        pelican = cls(settings, args.path, args.theme, args.output, markup, args.keep)
+        pelican = cls(settings, args.path, args.theme, args.output, markup, args.keep, args.plugins_path)
         if args.autoreload:
             while True:
                 try:

pelican/generators.py

@@ -8,6 +8,8 @@ import os
 import math
 import random
 
+from blinker import signal
+
 from jinja2 import Environment, FileSystemLoader
 from jinja2.exceptions import TemplateNotFound
 
@@ -92,6 +94,7 @@ class ArticlesGenerator(Generator):
         self.dates = {}
         self.tags = defaultdict(list)
         self.categories = defaultdict(list)
+        self.signal = {'pelican_article_generate_context' : signal('pelican_article_generate_context')}
         super(ArticlesGenerator, self).__init__(*args, **kwargs)
 
     def generate_feeds(self, writer):
@@ -200,6 +203,8 @@ class ArticlesGenerator(Generator):
                 and self.settings['FALLBACK_ON_FS_DATE']:
                     metadatas['date'] = datetime.fromtimestamp(os.stat(f).st_ctime)
 
+            self.signal['pelican_article_generate_context'].send(self, metadatas=metadatas)
+
             article = Article(content, metadatas, settings=self.settings,
                               filename=f)
             if not is_valid_content(article, f):

pelican/readers.py

@@ -49,9 +49,14 @@ class RstReader(Reader):
         rendered_content = core.publish_parts(text, writer_name='html',
                                               settings_overrides=extra_params)
         title = rendered_content.get('title')
+        subtitle = rendered_content.get('subtitle') or ''
         content = rendered_content.get('body')
+        
         if not metadatas.has_key('title'):
             metadatas['title'] = title
+        if not metadatas.has_key('subtitle'):
+            metadatas['subtitle'] = subtitle
+            
         return content, metadatas
 
 class MarkdownReader(Reader):

pelican/settings.py

@@ -37,6 +37,7 @@ _DEFAULT_CONFIG = {'PATH': None,
                    'WITH_PAGINATION': False,
                    'DEFAULT_PAGINATION': 5,
                    'DEFAULT_ORPHANS': 0,
+                   'PLUGINS_PATH': None,
                   }
 
 def read_settings(filename):

plugins_samples/global_license.py

@@ -0,0 +1,23 @@
+from blinker import signal
+
+"""
+License plugin for Pelican
+==========================
+
+Simply add license variable in article's context, which contain 
+the license text.
+
+Settings:
+---------
+
+Add LICENSE to your settings file to define default license.
+
+"""
+
+def add_license(generator, metadatas):
+    if 'license' not in metadatas.keys()\
+        and 'LICENSE' in generator.settings.keys():
+            metadatas['license'] = generator.settings['LICENSE']
+
+
+signal('pelican_article_generate_context').connect(add_license)

plugins_samples/gravatar.py

@@ -0,0 +1,39 @@
+import hashlib
+
+from blinker import signal
+"""
+Gravata plugin for Pelican
+==========================
+
+Simply add author_gravatar variable in article's context, which contain 
+the gravatar url.
+
+Settings:
+---------
+
+Add AUTHOR_EMAIL to your settings file to define default author email
+
+Article metadatas:
+------------------
+
+:email:  article's author email
+
+If one of them are defined the author_gravatar variable is added to 
+article's context.
+"""
+
+def add_gravatar(generator, metadatas):
+    
+    #first check email
+    if 'email' not in metadatas.keys()\
+        and 'AUTHOR_EMAIL' in generator.settings.keys():
+            metadatas['email'] = generator.settings['AUTHOR_EMAIL']
+            
+    #then add gravatar url
+    if 'email' in metadatas.keys():
+        gravatar_url = "http://www.gravatar.com/avatar/" + \
+                        hashlib.md5(metadatas['email'].lower()).hexdigest()
+        metadatas["author_gravatar"] = gravatar_url
+    
+    
+signal('pelican_article_generate_context').connect(add_gravatar)

plugins_samples/initialized.py

@@ -0,0 +1,7 @@
+from blinker import signal
+
+
+def test(sender):
+    print "%s initialized !!" % sender
+
+signal('pelican_initialized').connect(test)

setup.py

@@ -3,7 +3,7 @@ import sys
 
 VERSION = "2.6.0" # find a better way to do so.
 
-requires = ['feedgenerator', 'jinja2', 'pygments', 'docutils', 'Markdown']
+requires = ['feedgenerator', 'jinja2', 'pygments', 'docutils', 'Markdown', 'blinker']
 if sys.version_info < (2,7):
     requires.append('argparse')