plugins/summary.py

   1 """
   2 Summary
   3 -------
   4
   5 This plugin allows easy, variable length summaries directly embedded into the
   6 body of your articles.
   7 """
   8
   9 from __future__ import unicode_literals
  10 from bs4 import BeautifulSoup
  11 from pelican import signals
  12 from pelican.generators import ArticlesGenerator, StaticGenerator, PagesGenerator
  13 import re
  14
  15 def initialized(pelican):
  16     from pelican.settings import DEFAULT_CONFIG
  17     DEFAULT_CONFIG.setdefault('SUMMARY_BEGIN_MARKER',
  18                               '<!-- PELICAN_BEGIN_SUMMARY -->')
  19     DEFAULT_CONFIG.setdefault('SUMMARY_END_MARKER',
  20                               '<!-- PELICAN_END_SUMMARY -->')
  21     DEFAULT_CONFIG.setdefault('SUMMARY_USE_FIRST_PARAGRAPH', False)
  22     if pelican:
  23         pelican.settings.setdefault('SUMMARY_BEGIN_MARKER',
  24                                     '<!-- PELICAN_BEGIN_SUMMARY -->')
  25         pelican.settings.setdefault('SUMMARY_END_MARKER',
  26                                     '<!-- PELICAN_END_SUMMARY -->')
  27         pelican.settings.setdefault('SUMMARY_USE_FIRST_PARAGRAPH', False)
  28
  29 def extract_summary(instance):
  30     # if summary is already specified, use it
  31     # if there is no content, there's nothing to do
  32     if hasattr(instance, '_summary') or 'summary' in instance.metadata:
  33         instance.has_summary = True
  34         return
  35
  36     if not instance._content:
  37         instance.has_summary = False
  38         return
  39
  40     begin_marker = instance.settings['SUMMARY_BEGIN_MARKER']
  41     end_marker   = instance.settings['SUMMARY_END_MARKER']
  42     use_first_paragraph = instance.settings['SUMMARY_USE_FIRST_PARAGRAPH']
  43     remove_markers = True
  44
  45     content = instance._update_content(instance._content, instance.settings['SITEURL'])
  46     begin_summary = -1
  47     end_summary = -1
  48     if begin_marker:
  49         begin_summary = content.find(begin_marker)
  50     if end_marker:
  51         end_summary = content.find(end_marker)
  52
  53     if begin_summary == -1 and end_summary == -1 and use_first_paragraph:
  54         begin_marker, end_marker = '<p>', '</p>'
  55         remove_markers = False
  56         begin_summary = content.find(begin_marker)
  57         end_summary = content.find(end_marker)
  58
  59     if begin_summary == -1 and end_summary == -1:
  60         instance.has_summary = False
  61         return
  62
  63     # skip over the begin marker, if present
  64     if begin_summary == -1:
  65         begin_summary = 0
  66     else:
  67         begin_summary = begin_summary + len(begin_marker)
  68
  69     if end_summary == -1:
  70         end_summary = None
  71
  72     summary = content[begin_summary:end_summary]
  73
  74     if remove_markers:
  75         # remove the markers from the content
  76         if begin_summary:
  77             content = content.replace(begin_marker, '', 1)
  78         if end_summary:
  79             content = content.replace(end_marker, '', 1)
  80
  81     summary = str(BeautifulSoup(summary, 'html.parser'))
  82
  83     instance._content = content
  84     # default_status was added to Pelican Content objects after 3.7.1.
  85     # Its use here is strictly to decide on how to set the summary.
  86     # There's probably a better way to do this but I couldn't find it.
  87     if hasattr(instance, 'default_status'):
  88         instance.metadata['summary'] = summary
  89     else:
  90         instance._summary = summary
  91     instance.has_summary = True
  92
  93
  94 def run_plugin(generators):
  95     for generator in generators:
  96         if isinstance(generator, ArticlesGenerator):
  97             for article in generator.articles:
  98                 extract_summary(article)
  99         elif isinstance(generator, PagesGenerator):
 100             for page in generator.pages:
 101                 extract_summary(page)
 102
 103
 104 def register():
 105     signals.initialized.connect(initialized)
 106     try:
 107         signals.all_generators_finalized.connect(run_plugin)
 108     except AttributeError:
 109         # NOTE: This results in #314 so shouldn't really be relied on
 110         # https://github.com/getpelican/pelican-plugins/issues/314
 111         signals.content_object_init.connect(extract_summary)