Merge pull request #318 from MeirKriheli/master

Generator to compile less css files

docs/index.rst

@@ -23,6 +23,7 @@ Pelican currently supports:
 * Publication of articles in multiple languages
 * Atom/RSS feeds
 * Code syntax highlighting
+* Compilation of less css (optional)
 * Import from WordPress, Dotclear, or RSS feeds
 * Integration with external tools: Twitter, Google Analytics, etc. (optional)
 

docs/settings.rst

@@ -82,10 +82,15 @@ Setting name (default value)                        What does it do?
                                                     generated HTML, using the `Typogrify
                                                     <http://static.mintchaos.com/projects/typogrify/>`_
                                                     library
+`LESS_GENERATOR` (``FALSE``)                        Set to True or complete path to `lessc` (if not
+                                                    found in system PATH) to enable compiling less
+                                                    css files. Requires installation of `less css`_.
 ================================================    =====================================================
 
 .. [#] Default is the system locale.
 
+.. _less css: http://lesscss.org/
+
 
 URL settings
 ------------

pelican/__init__.py

@@ -6,7 +6,7 @@ import logging
 import argparse
 
 from pelican.generators import (ArticlesGenerator, PagesGenerator,
-        StaticGenerator, PdfGenerator)
+        StaticGenerator, PdfGenerator, LessCSSGenerator)
 from pelican.log import init
 from pelican.settings import read_settings, _DEFAULT_CONFIG
 from pelican.utils import clean_output_dir, files_changed
@@ -134,6 +134,8 @@ class Pelican(object):
         generators = [ArticlesGenerator, PagesGenerator, StaticGenerator]
         if self.settings['PDF_GENERATOR']:
             generators.append(PdfGenerator)
+        if self.settings['LESS_GENERATOR']: # can be True or PATH to lessc
+            generators.append(LessCSSGenerator)
         return generators
 
     def get_writer(self):

pelican/generators.py

@@ -4,6 +4,7 @@ import math
 import random
 import logging
 import datetime
+import subprocess
 
 from collections import defaultdict
 from functools import partial
@@ -414,3 +415,50 @@ class PdfGenerator(Generator):
 
         for page in self.context['pages']:
             self._create_pdf(page, pdf_path)
+
+
+class LessCSSGenerator(Generator):
+    """Compile less css files."""
+
+    def _compile(self, less_file, source_dir, dest_dir):
+        base = os.path.relpath(less_file, source_dir)
+        target = os.path.splitext(
+                os.path.join(dest_dir, base))[0] + '.css'
+        target_dir = os.path.dirname(target)
+
+        if not os.path.exists(target_dir):
+            try:
+                os.makedirs(target_dir)
+            except OSError:
+                logger.error("Couldn't create the less css output folder in " +
+                        target_dir)
+
+        subprocess.call([self._lessc, less_file, target])
+        logger.info(u' [ok] compiled %s' % base)
+
+    def generate_output(self, writer=None):
+        logger.info(u' Compiling less css')
+
+        # store out compiler here, so it won't be evaulted on each run of
+        # _compile
+        lg = self.settings['LESS_GENERATOR']
+        self._lessc = lg if isinstance(lg, basestring) else 'lessc'
+
+        # walk static paths
+        for static_path in self.settings['STATIC_PATHS']:
+            for f in self.get_files(
+                    os.path.join(self.path, static_path),
+                    extensions=['less']):
+
+                self._compile(f, self.path, self.output_path)
+
+        # walk theme static paths
+        theme_output_path = os.path.join(self.output_path, 'theme')
+
+        for static_path in self.settings['THEME_STATIC_PATHS']:
+            theme_static_path = os.path.join(self.theme, static_path)
+            for f in self.get_files(
+                    theme_static_path,
+                    extensions=['less']):
+
+                self._compile(f, theme_static_path, theme_output_path)

pelican/settings.py

@@ -67,6 +67,7 @@ _DEFAULT_CONFIG = {'PATH': '.',
                    'DEFAULT_STATUS': 'published',
                    'ARTICLE_PERMALINK_STRUCTURE': '',
                    'TYPOGRIFY': False,
+                   'LESS_GENERATOR': False,
                    }
 
 

tests/support.py

@@ -4,6 +4,8 @@ __all__ = [
     'unittest',
 ]
 
+import os
+import subprocess
 from contextlib import contextmanager
 from tempfile import mkdtemp
 from shutil import rmtree
@@ -35,3 +37,21 @@ def get_article(title, slug, content, lang, extra_metadata=None):
     if extra_metadata is not None:
         metadata.update(extra_metadata)
     return Article(content, metadata=metadata)
+
+
+def skipIfNoExecutable(executable, valid_exit_code=1):
+    """Tries to run an executable to make sure it's in the path, Skips the tests
+    if not found.
+    """
+
+    # calling with no params the command should exit with 1
+    with open(os.devnull, 'w') as fnull:
+        try:
+            res = subprocess.call(executable, stdout=fnull, stderr=fnull)
+        except OSError:
+            res = None
+
+    if res != valid_exit_code:
+        return unittest.skip('{0} compiler not found'.format(executable))
+
+    return lambda func: func

tests/test_generators.py

@@ -2,10 +2,12 @@
 
 from mock import MagicMock
 import os
+import re
+import subprocess
 
-from pelican.generators import ArticlesGenerator
+from pelican.generators import ArticlesGenerator, LessCSSGenerator
 from pelican.settings import _DEFAULT_CONFIG
-from .support import unittest
+from .support import unittest, temporary_folder, skipIfNoExecutable
 
 CUR_DIR = os.path.dirname(__file__)
 
@@ -46,3 +48,49 @@ class TestArticlesGenerator(unittest.TestCase):
             elif relfilepath == "article_without_category.rst":
                 self.assertEquals(article.category.name, 'Default')
 
+
+class TestLessCSSGenerator(unittest.TestCase):
+
+    LESS_CONTENT = """
+        @color: #4D926F;
+
+        #header {
+          color: @color;
+        }
+        h2 {
+          color: @color;
+        }
+    """
+
+    @skipIfNoExecutable('lessc')
+    def test_less_compiler(self):
+
+        settings = _DEFAULT_CONFIG.copy()
+        settings['STATIC_PATHS'] = ['static']
+        settings['LESS_GENERATOR'] = True
+
+        # we'll nest here for py < 2.7 compat
+        with temporary_folder() as temp_content:
+            with temporary_folder() as temp_output:
+                generator = LessCSSGenerator(None, settings, temp_content,
+                                    _DEFAULT_CONFIG['THEME'], temp_output, None)
+
+                # create a dummy less file
+                less_dir = os.path.join(temp_content, 'static', 'css')
+                less_filename = os.path.join(less_dir, 'test.less')
+
+                less_output = os.path.join(temp_output, 'static', 'css',
+                                    'test.css')
+
+                os.makedirs(less_dir)
+                with open(less_filename, 'w') as less_file:
+                    less_file.write(self.LESS_CONTENT)
+
+                generator.generate_output()
+
+                # we have the file ?
+                self.assertTrue(os.path.exists(less_output))
+
+                # was it compiled ?
+                self.assertIsNotNone(re.search(r'^\s+color:\s*#4D926F;$',
+                    open(less_output).read(), re.MULTILINE | re.IGNORECASE))