46 lines
1.3 KiB
Ruby
46 lines
1.3 KiB
Ruby
class FetchAtomService < BaseService
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def call(url)
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response = http_client.head(url)
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Rails.logger.debug "Remote status HEAD request returned code #{response.code}"
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return nil if response.code != 200
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if response.mime_type == 'application/atom+xml'
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return [url, fetch(url)]
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elsif !response['Link'].blank?
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return process_headers(url, response)
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else
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return process_html(fetch(url))
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end
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end
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private
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def process_html(body)
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Rails.logger.debug 'Processing HTML'
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page = Nokogiri::HTML(body)
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alternate_link = page.xpath('//link[@rel="alternate"]').find { |link| link['type'] == 'application/atom+xml' }
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return nil if alternate_link.nil?
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return [alternate_link['href'], fetch(alternate_link['href'])]
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end
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def process_headers(url, response)
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Rails.logger.debug 'Processing link header'
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link_header = LinkHeader.parse(response['Link'].is_a?(Array) ? response['Link'].first : response['Link'])
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alternate_link = link_header.find_link(['rel', 'alternate'], ['type', 'application/atom+xml'])
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return process_html(fetch(url)) if alternate_link.nil?
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return [alternate_link.href, fetch(alternate_link.href)]
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end
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def fetch(url)
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http_client.get(url).to_s
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end
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def http_client
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HTTP.timeout(:per_operation, write: 20, connect: 20, read: 50).follow
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end
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end
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