26 lines
802 B
Ruby
26 lines
802 B
Ruby
# frozen_string_literal: true
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# Generated HTML is transformed back to GFM by app/assets/javascripts/behaviors/markdown/nodes/image.js
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module Banzai
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module Filter
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# HTML filter that moves the value of image `src` attributes to `data-src`
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# so they can be lazy loaded. Also sets decoding to 'async' so that the
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# decoding of images doesn't block the loading of other content.
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class ImageLazyLoadFilter < HTML::Pipeline::Filter
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CSS = 'img'
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XPATH = Gitlab::Utils::Nokogiri.css_to_xpath(CSS).freeze
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def call
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doc.xpath(XPATH).each do |img|
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img['decoding'] = 'async'
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img.add_class('lazy')
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img['data-src'] = img['src']
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img['src'] = LazyImageTagHelper.placeholder_image
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end
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doc
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end
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end
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end
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end
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