ファイル
btrc-hub/backend/app/services/preview/http_fetcher.rb
T
みてるぞ 6c451d260f サムネ取得 API 見直し (#398) (#402)
Reviewed-on: #402
Co-authored-by: miteruzo <miteruzo@naver.com>
Co-committed-by: miteruzo <miteruzo@naver.com>
2026-07-10 01:27:11 +09:00

123 行
4.4 KiB
Ruby

require 'net/http'
require 'json'
module Preview
class HttpFetcher
class FetchFailed < StandardError; end
class FetchTimeout < FetchFailed; end
class ResponseTooLarge < FetchFailed; end
MAX_REDIRECTS = 5
DEFAULT_MAX_BYTES = 5.megabytes
Response = Data.define(:body, :content_type, :url)
def self.fetch(raw_url, max_bytes: DEFAULT_MAX_BYTES, redirects: MAX_REDIRECTS)
uri, addresses = UrlSafety.validate(raw_url)
response = request(uri, addresses.first, max_bytes)
if response.is_a?(Net::HTTPRedirection)
location = response['location']
if redirects.zero?
log_failure(:redirect_limit,
url: uri.to_s,
redirects:,
location:,
content_type: response['content-type'],
content_length: response['content-length'])
raise FetchFailed, 'redirect が多すぎます.'
end
if location.blank?
log_failure(:blank_redirect_location,
url: uri.to_s,
redirects:,
content_type: response['content-type'],
content_length: response['content-length'])
raise FetchFailed, 'redirect 先が不正です.'
end
redirect_url =
begin
URI.join(uri, location).to_s
rescue URI::InvalidURIError => e
log_failure(:invalid_redirect_location,
url: uri.to_s,
redirects:,
location:,
error: e.class.name,
message: e.message)
raise FetchFailed, 'redirect 先が不正です.'
end
return fetch(redirect_url, max_bytes:, redirects: redirects - 1)
end
unless response.is_a?(Net::HTTPSuccess)
log_failure(:http_status,
url: uri.to_s,
code: response.code,
content_type: response['content-type'],
content_length: response['content-length'])
raise FetchFailed, "外部サーバーが HTTP #{ response.code } を返しました."
end
Response.new(response.body, response['content-type'].to_s, uri.to_s)
rescue Net::OpenTimeout, Net::ReadTimeout, Timeout::Error => e
log_failure(:timeout, url: uri&.to_s || raw_url, error: e.class.name, message: e.message)
raise FetchTimeout, e.message
rescue SocketError, SystemCallError, OpenSSL::SSL::SSLError, EOFError => e
log_failure(:network_error, url: uri&.to_s || raw_url, error: e.class.name, message: e.message)
raise FetchFailed, e.message
end
def self.request(uri, ip_address, max_bytes)
http = Net::HTTP.new(uri.host, uri.port)
http.ipaddr = ip_address
http.use_ssl = uri.scheme == 'https'
http.open_timeout = 5
http.read_timeout = 8
http.write_timeout = 5
request = Net::HTTP::Get.new(uri)
request['User-Agent'] = 'BTRC-Hub thumbnail preview'
request['Accept'] = 'text/html,image/*;q=0.9,*/*;q=0.1'
http.request(request) do |response|
length = response['content-length'].to_i
if length > max_bytes
log_failure(:response_too_large,
url: uri.to_s,
content_type: response['content-type'],
content_length: response['content-length'],
max_bytes:)
raise ResponseTooLarge, '外部データが大きすぎます.'
end
body = +''
response.read_body do |chunk|
body << chunk
next unless body.bytesize > max_bytes
log_failure(:response_too_large,
url: uri.to_s,
content_type: response['content-type'],
content_length: response['content-length'],
bytes_read: body.bytesize,
max_bytes:)
raise ResponseTooLarge, '外部データが大きすぎます.'
end
response.instance_variable_set(:@body, body)
response.instance_variable_set(:@read, true)
return response
end
end
def self.log_failure(reason, **payload)
Rails.logger.warn("preview_http_fetcher_failure #{ { reason:, **payload }.to_json }")
end
private_class_method :request, :log_failure
end
end