Class: MetaInspector::Parsers::ImagesParser

Inherits:
Base
  • Object
show all
Includes:
Enumerable
Defined in:
lib/meta_inspector/parsers/images.rb

Instance Method Summary collapse

Constructor Details

#initialize(main_parser, options = {}) ⇒ ImagesParser

Returns a new instance of ImagesParser.


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# File 'lib/meta_inspector/parsers/images.rb', line 11

def initialize(main_parser, options = {})
  @download_images = options[:download_images]
  super(main_parser)
end

Instance Method Details

#bestObject

Returns either the Facebook Open Graph image, twitter suggested image or the largest image in the image collection


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# File 'lib/meta_inspector/parsers/images.rb', line 22

def best
  owner_suggested || largest
end

#faviconObject

Return favicon url if exist


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# File 'lib/meta_inspector/parsers/images.rb', line 73

def favicon
  query = '//link[@rel="icon" or contains(@rel, "shortcut")]'
  value = parsed.xpath(query)[0].attributes['href'].value
  @favicon ||= URL.absolutify(value, base_url, normalize: false)
rescue
  nil
end

#imagesObject


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# File 'lib/meta_inspector/parsers/images.rb', line 16

def images
  self
end

#largestObject

Returns the largest image from the image collection, filtered for images that are more square than 10:1 or 1:10


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# File 'lib/meta_inspector/parsers/images.rb', line 60

def largest
  @largest_image ||= begin
    imgs_with_size = with_size.dup
    imgs_with_size.keep_if do |url, width, height|
      ratio = width.to_f / height.to_f
      ratio > 0.1 && ratio < 10
    end
    url, width, height = imgs_with_size.first
    url
  end
end

#owner_suggestedObject

Returns the parsed image from Facebook's open graph property tags Most major websites now define this property and is usually relevant See doc at developers.facebook.com/docs/opengraph/ If none found, tries with Twitter image


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# File 'lib/meta_inspector/parsers/images.rb', line 30

def owner_suggested
  suggested_img = content_of(meta['og:image']) || content_of(meta['twitter:image'])
  URL.absolutify(suggested_img, base_url, normalize: false) if suggested_img
end

#with_sizeObject

Returns an array of [img_url, width, height] sorted by image area (width * height)


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# File 'lib/meta_inspector/parsers/images.rb', line 36

def with_size
  @with_size ||= begin
    img_nodes = parsed.search('//img').select{ |img_node| img_node['src'] }
    imgs_with_size = img_nodes.map do |img_node|
      [URL.absolutify(img_node['src'], base_url, normalize: false), img_node['width'], img_node['height']]
    end
    imgs_with_size.uniq! { |url, width, height| url }
    if @download_images
      imgs_with_size.map! do |url, width, height|
        width, height = FastImage.size(url) if width.nil? || height.nil?
        [url, width.to_i, height.to_i]
      end
    else
      imgs_with_size.map! do |url, width, height|
        width, height = [0, 0] if width.nil? || height.nil?
        [url, width.to_i, height.to_i]
      end
    end
    imgs_with_size.sort_by { |url, width, height| -(width.to_i * height.to_i) }
  end
end