20 lines
623 B
Python
20 lines
623 B
Python
from copy import deepcopy
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from django.templatetags.static import static
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from lxml import html
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def lazy_load(tree):
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blank = static('blank.gif')
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for img in tree.xpath('.//img'):
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src = img.get('src', '')
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if src.startswith('data') or '-math' in img.get('class', ''):
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continue
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noscript = html.Element('noscript')
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copy = deepcopy(img)
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copy.tail = ''
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noscript.append(copy)
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img.addprevious(noscript)
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img.set('data-src', src)
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img.set('src', blank)
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img.set('class', img.get('class') + ' unveil' if img.get('class') else 'unveil')
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