Require a blog config for the blog extension.

handroll/configuration.py

@@ -20,6 +20,9 @@ def __init__(self):
         self.outdir = None
         self.timing = None
 
+        # Keep the parser to allow extensions to get configuration file data.
+        self.parser = ConfigParser()
+
     def load_from_arguments(self, args):
         """Load any configuration attributes from the provided command line
         arguments. Arguments have the highest precedent so overwrite any other
@@ -33,13 +36,12 @@ def load_from_arguments(self, args):
     def load_from_file(self, config_file):
         """Load any configuration attributes from the provided config file."""
         with open(config_file, 'r') as f:
-            parser = ConfigParser()
-            parser.readfp(f)
-            if parser.has_option('site', 'outdir'):
+            self.parser.readfp(f)
+            if self.parser.has_option('site', 'outdir'):
                 self.outdir = os.path.abspath(os.path.expanduser(
-                    parser.get('site', 'outdir')))
-            if parser.has_section('site'):
-                self._find_extensions(parser)
+                    self.parser.get('site', 'outdir')))
+            if self.parser.has_section('site'):
+                self._find_extensions(self.parser)
 
     def _find_extensions(self, parser):
         """Check if the site options have extensions to enable."""

handroll/extensions/blog.py

@@ -15,12 +15,19 @@ class BlogExtension(Extension):
     """Track files marked as blog entries and generate a feed."""
 
     handle_frontmatter_loaded = True
+    handle_pre_composition = True
     handle_post_composition = True
 
     def __init__(self, config):
         super(BlogExtension, self).__init__(config)
         self.posts = []
 
+    def on_pre_composition(self, director):
+        """Check that all the required configuration exists."""
+        if not self._config.parser.has_section('blog'):
+            raise AbortError(
+                _('A blog section is missing in the configuration file.'))
+
     def on_frontmatter_loaded(self, source_file, frontmatter):
         """Scan for blog posts.
 

handroll/tests/factory.py

@@ -3,12 +3,19 @@
 import os
 import tempfile
 
+from handroll.configuration import Configuration
+from handroll.director import Director
 from handroll.site import Site
 
 
 class Factory(object):
     """A factory to produce commonly needed objects"""
 
+    def make_director(self):
+        config = Configuration()
+        site = self.make_site()
+        return Director(config, site, [])
+
     def make_site(self):
         """Make a valid site instance."""
         site = tempfile.mkdtemp()

handroll/tests/test_extensions.py

@@ -16,6 +16,7 @@ class TestExtensionLoader(TestCase):
     def tearDown(self):
         # Clean up any attached extension instance.
         signals.frontmatter_loaded.receivers.clear()
+        signals.pre_composition.receivers.clear()
         signals.post_composition.receivers.clear()
 
     def test_loads_available_extensions(self):
@@ -88,6 +89,7 @@ class TestBlogExtension(TestCase):
     def tearDown(self):
         # Clean up any attached extension instance.
         signals.frontmatter_loaded.receivers.clear()
+        signals.pre_composition.receivers.clear()
         signals.post_composition.receivers.clear()
 
     def test_handles_frontmatter_loaded(self):
@@ -114,3 +116,13 @@ def test_blog_must_be_boolean(self):
         self.assertRaises(
             AbortError, extension.on_frontmatter_loaded, 'animaniacs.md',
             {'blog': 'crazy'})
+
+    def test_handles_pre_composition(self):
+        extension = BlogExtension(None)
+        self.assertTrue(extension.handle_pre_composition)
+
+    def test_requires_blog_section(self):
+        """A config with no blog section aborts."""
+        director = self.factory.make_director()
+        extension = BlogExtension(director.config)
+        self.assertRaises(AbortError, extension.on_pre_composition, director)