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300f835703
This PR changes the rescue block to rescue only Net::TimeoutError exceptions and removes the log line to prevent clutter the logs with errors that are ignored. Other errors can bubble up because they're errors we probably want to know about
98 lines
2.7 KiB
Ruby
98 lines
2.7 KiB
Ruby
# frozen_string_literal: true
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module RetrieveTitle
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CRAWL_TIMEOUT = 1
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def self.crawl(url, max_redirects: nil, initial_https_redirect_ignore_limit: false)
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fetch_title(
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url,
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max_redirects: max_redirects,
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initial_https_redirect_ignore_limit: initial_https_redirect_ignore_limit
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)
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rescue Net::ReadTimeout
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# do nothing for Net::ReadTimeout errors
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end
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def self.extract_title(html, encoding = nil)
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title = nil
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if html =~ /<title>/ && html !~ /<\/title>/
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return nil
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end
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if doc = Nokogiri::HTML5(html, nil, encoding)
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title = doc.at('title')&.inner_text
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# A horrible hack - YouTube uses `document.title` to populate the title
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# for some reason. For any other site than YouTube this wouldn't be worth it.
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if title == "YouTube" && html =~ /document\.title *= *"(.*)";/
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title = Regexp.last_match[1].sub(/ - YouTube$/, '')
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end
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if !title && node = doc.at('meta[property="og:title"]')
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title = node['content']
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end
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end
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if title.present?
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title.gsub!(/\n/, ' ')
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title.gsub!(/ +/, ' ')
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title.strip!
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return title
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end
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nil
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end
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private
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def self.max_chunk_size(uri)
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# Exception for sites that leave the title until very late.
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return 500 if uri.host =~ /(^|\.)amazon\.(com|ca|co\.uk|es|fr|de|it|com\.au|com\.br|cn|in|co\.jp|com\.mx)$/
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return 300 if uri.host =~ /(^|\.)youtube\.com$/ || uri.host =~ /(^|\.)youtu\.be$/
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return 50 if uri.host =~ /(^|\.)github\.com$/
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# default is 20k
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20
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end
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# Fetch the beginning of a HTML document at a url
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def self.fetch_title(url, max_redirects: nil, initial_https_redirect_ignore_limit: false)
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fd = FinalDestination.new(
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url,
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timeout: CRAWL_TIMEOUT,
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stop_at_blocked_pages: true,
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max_redirects: max_redirects,
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initial_https_redirect_ignore_limit: initial_https_redirect_ignore_limit
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)
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current = nil
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title = nil
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encoding = nil
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fd.get do |_response, chunk, uri|
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unless Net::HTTPRedirection === _response
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throw :done if uri.blank?
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if current
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current << chunk
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else
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current = chunk
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end
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if !encoding && content_type = _response['content-type']&.strip&.downcase
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if content_type =~ /charset="?([a-z0-9_-]+)"?/
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encoding = Regexp.last_match(1)
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if !Encoding.list.map(&:name).map(&:downcase).include?(encoding)
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encoding = nil
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end
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end
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end
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max_size = max_chunk_size(uri) * 1024
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title = extract_title(current, encoding)
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throw :done if title || max_size < current.length
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end
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end
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title
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end
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end
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