| """HTML utilities suitable for global use.""" |
| |
| import re |
| import string |
| |
| from django.utils.safestring import SafeData, mark_safe |
| from django.utils.encoding import force_unicode |
| from django.utils.functional import allow_lazy |
| from django.utils.http import urlquote |
| |
| # Configuration for urlize() function. |
| LEADING_PUNCTUATION = ['(', '<', '<'] |
| TRAILING_PUNCTUATION = ['.', ',', ')', '>', '\n', '>'] |
| |
| # List of possible strings used for bullets in bulleted lists. |
| DOTS = ['·', '*', '\xe2\x80\xa2', '•', '•', '•'] |
| |
| unencoded_ampersands_re = re.compile(r'&(?!(\w+|#\d+);)') |
| word_split_re = re.compile(r'(\s+)') |
| punctuation_re = re.compile('^(?P<lead>(?:%s)*)(?P<middle>.*?)(?P<trail>(?:%s)*)$' % \ |
| ('|'.join([re.escape(x) for x in LEADING_PUNCTUATION]), |
| '|'.join([re.escape(x) for x in TRAILING_PUNCTUATION]))) |
| simple_email_re = re.compile(r'^\S+@[a-zA-Z0-9._-]+\.[a-zA-Z0-9._-]+$') |
| link_target_attribute_re = re.compile(r'(<a [^>]*?)target=[^\s>]+') |
| html_gunk_re = re.compile(r'(?:<br clear="all">|<i><\/i>|<b><\/b>|<em><\/em>|<strong><\/strong>|<\/?smallcaps>|<\/?uppercase>)', re.IGNORECASE) |
| hard_coded_bullets_re = re.compile(r'((?:<p>(?:%s).*?[a-zA-Z].*?</p>\s*)+)' % '|'.join([re.escape(x) for x in DOTS]), re.DOTALL) |
| trailing_empty_content_re = re.compile(r'(?:<p>(?: |\s|<br \/>)*?</p>\s*)+\Z') |
| del x # Temporary variable |
| |
| def escape(html): |
| """Returns the given HTML with ampersands, quotes and carets encoded.""" |
| return mark_safe(force_unicode(html).replace('&', '&').replace('<', '<').replace('>', '>').replace('"', '"').replace("'", ''')) |
| escape = allow_lazy(escape, unicode) |
| |
| def conditional_escape(html): |
| """ |
| Similar to escape(), except that it doesn't operate on pre-escaped strings. |
| """ |
| if isinstance(html, SafeData): |
| return html |
| else: |
| return escape(html) |
| |
| def linebreaks(value, autoescape=False): |
| """Converts newlines into <p> and <br />s.""" |
| value = re.sub(r'\r\n|\r|\n', '\n', force_unicode(value)) # normalize newlines |
| paras = re.split('\n{2,}', value) |
| if autoescape: |
| paras = [u'<p>%s</p>' % escape(p.strip()).replace('\n', '<br />') for p in paras] |
| else: |
| paras = [u'<p>%s</p>' % p.strip().replace('\n', '<br />') for p in paras] |
| return u'\n\n'.join(paras) |
| linebreaks = allow_lazy(linebreaks, unicode) |
| |
| def strip_tags(value): |
| """Returns the given HTML with all tags stripped.""" |
| return re.sub(r'<[^>]*?>', '', force_unicode(value)) |
| strip_tags = allow_lazy(strip_tags) |
| |
| def strip_spaces_between_tags(value): |
| """Returns the given HTML with spaces between tags removed.""" |
| return re.sub(r'>\s+<', '><', force_unicode(value)) |
| strip_spaces_between_tags = allow_lazy(strip_spaces_between_tags, unicode) |
| |
| def strip_entities(value): |
| """Returns the given HTML with all entities (&something;) stripped.""" |
| return re.sub(r'&(?:\w+|#\d+);', '', force_unicode(value)) |
| strip_entities = allow_lazy(strip_entities, unicode) |
| |
| def fix_ampersands(value): |
| """Returns the given HTML with all unencoded ampersands encoded correctly.""" |
| return unencoded_ampersands_re.sub('&', force_unicode(value)) |
| fix_ampersands = allow_lazy(fix_ampersands, unicode) |
| |
| def urlize(text, trim_url_limit=None, nofollow=False, autoescape=False): |
| """ |
| Converts any URLs in text into clickable links. |
| |
| Works on http://, https://, www. links and links ending in .org, .net or |
| .com. Links can have trailing punctuation (periods, commas, close-parens) |
| and leading punctuation (opening parens) and it'll still do the right |
| thing. |
| |
| If trim_url_limit is not None, the URLs in link text longer than this limit |
| will truncated to trim_url_limit-3 characters and appended with an elipsis. |
| |
| If nofollow is True, the URLs in link text will get a rel="nofollow" |
| attribute. |
| |
| If autoescape is True, the link text and URLs will get autoescaped. |
| """ |
| trim_url = lambda x, limit=trim_url_limit: limit is not None and (len(x) > limit and ('%s...' % x[:max(0, limit - 3)])) or x |
| safe_input = isinstance(text, SafeData) |
| words = word_split_re.split(force_unicode(text)) |
| nofollow_attr = nofollow and ' rel="nofollow"' or '' |
| for i, word in enumerate(words): |
| match = None |
| if '.' in word or '@' in word or ':' in word: |
| match = punctuation_re.match(word) |
| if match: |
| lead, middle, trail = match.groups() |
| # Make URL we want to point to. |
| url = None |
| if middle.startswith('http://') or middle.startswith('https://'): |
| url = urlquote(middle, safe='/&=:;#?+*') |
| elif middle.startswith('www.') or ('@' not in middle and \ |
| middle and middle[0] in string.ascii_letters + string.digits and \ |
| (middle.endswith('.org') or middle.endswith('.net') or middle.endswith('.com'))): |
| url = urlquote('http://%s' % middle, safe='/&=:;#?+*') |
| elif '@' in middle and not ':' in middle and simple_email_re.match(middle): |
| url = 'mailto:%s' % middle |
| nofollow_attr = '' |
| # Make link. |
| if url: |
| trimmed = trim_url(middle) |
| if autoescape and not safe_input: |
| lead, trail = escape(lead), escape(trail) |
| url, trimmed = escape(url), escape(trimmed) |
| middle = '<a href="%s"%s>%s</a>' % (url, nofollow_attr, trimmed) |
| words[i] = mark_safe('%s%s%s' % (lead, middle, trail)) |
| else: |
| if safe_input: |
| words[i] = mark_safe(word) |
| elif autoescape: |
| words[i] = escape(word) |
| elif safe_input: |
| words[i] = mark_safe(word) |
| elif autoescape: |
| words[i] = escape(word) |
| return u''.join(words) |
| urlize = allow_lazy(urlize, unicode) |
| |
| def clean_html(text): |
| """ |
| Clean the given HTML. Specifically, do the following: |
| * Convert <b> and <i> to <strong> and <em>. |
| * Encode all ampersands correctly. |
| * Remove all "target" attributes from <a> tags. |
| * Remove extraneous HTML, such as presentational tags that open and |
| immediately close and <br clear="all">. |
| * Convert hard-coded bullets into HTML unordered lists. |
| * Remove stuff like "<p> </p>", but only if it's at the |
| bottom of the text. |
| """ |
| from django.utils.text import normalize_newlines |
| text = normalize_newlines(force_unicode(text)) |
| text = re.sub(r'<(/?)\s*b\s*>', '<\\1strong>', text) |
| text = re.sub(r'<(/?)\s*i\s*>', '<\\1em>', text) |
| text = fix_ampersands(text) |
| # Remove all target="" attributes from <a> tags. |
| text = link_target_attribute_re.sub('\\1', text) |
| # Trim stupid HTML such as <br clear="all">. |
| text = html_gunk_re.sub('', text) |
| # Convert hard-coded bullets into HTML unordered lists. |
| def replace_p_tags(match): |
| s = match.group().replace('</p>', '</li>') |
| for d in DOTS: |
| s = s.replace('<p>%s' % d, '<li>') |
| return u'<ul>\n%s\n</ul>' % s |
| text = hard_coded_bullets_re.sub(replace_p_tags, text) |
| # Remove stuff like "<p> </p>", but only if it's at the bottom |
| # of the text. |
| text = trailing_empty_content_re.sub('', text) |
| return text |
| clean_html = allow_lazy(clean_html, unicode) |
