Support for custom urls for different categories of article

custom_article_urls/README.md

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+#Custom Article URLs#
+
+Adds support for defining different default urls for different categories, or 
+different subcategories if using the subcategory plugin.
+
+##Usage##
+
+After adding `custom_article_urls` to your `PLUGINS` add a `CUSTOM_ARTICLE_URLS`
+setting, which is a dictionary of rules. The rules are also a dictionary,
+consisting of the `URL` and the `SAVE_AS` values. 
+
+For example, if you had two categories, Category 1 and Category 2 and you
+would like Category 1 saved as category-1/article-slug/ and Category 2 saved as
+/year/month/article-slug/ you would add:
+
+    CUSTOM_ARTICLE_URLS = {
+        'Category 1': {'URL': '{category}/{slug}/,
+            'SAVE_AS': '{category}/{slug}/index.html},
+        'Category 2': {'URL': '{date:%Y}/{date:%B}/{slug}/,
+            'SAVE_AS': '{date:%Y}/{date:%B}/{slug}/index.html},
+        }
+
+If had any other categories they would use the default `ARTICLE_SAVE_AS`
+and `ARTICLE_URL`
+
+If you are using the subcategory plugin, you can define them the same way.
+For example if Category 1 had a subcategory Sub Category you could define
+it's rules with
+
+    'Category 1/Sub Category`: ...
+
+##Other Usage: Article Metadata##
+
+If you define a url and save_as in your articles metadata, then this plugin
+will not alter that value. So you can still specify special one off urls as 
+normal.

custom_article_urls/__init__.py

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+from .custom_article_urls import *

custom_article_urls/custom_article_urls.py

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+# -*- coding: utf-8 -*-
+"""
+@Author: Alistair Magee
+
+Adds ability to specify custom urls for different categories 
+(or subcategories if using subcategory plugin) of article
+using a dictionary stored in pelican settings file as
+{category: {article_url_structure: stirng, article_save_as: string}}
+"""
+from pelican import signals
+from pelican import contents
+
+from pelican.contents import Content, Category
+from functools import partial
+from six import text_type
+
+def recursive_name(self):
+    if type(self) is Category:
+        return self.name
+    else:
+        return '{}/{}'.format(recursive_name(self.parent), self.name)
+
+def custom_url(generator, metadata):
+    if 'CUSTOM_ARTICLE_URLS' in generator.settings:
+        custom_urls = generator.settings['CUSTOM_ARTICLE_URLS']
+        category = text_type(metadata['category'])
+        pattern_matched = {}
+        
+        if category in custom_urls:
+            pattern_matched = custom_urls[category]
+
+        if 'subcategories' in metadata: #using subcategory plugin
+            for subcategory in metadata['subcategories']:
+                subcategory_name = recursive_name(subcategory)
+                if subcategory_name in custom_urls:
+                    pattern_matched = custom_urls[subcategory_name]
+
+        if pattern_matched:
+            #only alter url if hasn't been set in the metdata
+            if ('url', 'save_as') in metadata:
+                """ if both url and save_as are set in the metadata already
+                then there is already a custom url set, skip this one
+                """
+                pass
+            else:
+                temp_article = Content(None, metadata=metadata)
+                url_format = pattern_matched['URL']
+                save_as_format = pattern_matched['SAVE_AS']
+                url = url_format.format(**temp_article.url_format)
+                save_as = save_as_format.format(**temp_article.url_format)
+                metadata.update({'url': url, 'save_as': save_as})
+
+        
+def register():
+    signals.article_generator_context.connect(custom_url)