This script collects domains from your Chrome history for the default profile and checks to see if they are being proxied through Cloudflare by checking presence of a header.

check_cloudflare.rb

# Except sqlite3 all the libraries are standard that should be present with a Ruby installation.
# If you don't have sqlite3 installed. Use `gem install sqlite3`

require 'fileutils'
require 'sqlite3'
require 'uri'
require 'net/http'
require 'set'
require 'thread'

chrome_history_location = "#{ENV['HOME']}/Library/Application\ Support/Google/Chrome/Default/History"
temp_location = "/tmp/Chrome_history"
FileUtils.cp(chrome_history_location, temp_location)

sqlite_db = SQLite3::Database.new temp_location
chrome_history = sqlite_db.execute('SELECT DISTINCT(url) FROM urls;').flatten; nil

FileUtils.rm([temp_location])

domain_set = Set.new
cloudflare_set = Set.new
query_uris = Array.new

chrome_history.each do |url|
  host = URI.parse(url).host rescue nil
  query_uris += [URI::HTTPS.build({host: host}), URI::HTTP.build({host: host})] if !domain_set.include?(host) && !host.nil?
  domain_set.add(host)
end; nil

uri_mutex, set_mutex, read_mutex = Mutex.new, Mutex.new, Mutex.new
(1..16).map do
  Thread.new(query_uris, cloudflare_set) do |query_uris, cloudflare_set|
    while !(uri = uri_mutex.synchronize { query_uris.pop }).nil?
      cf_header_present = !Net::HTTP.get_response(uri)['cf-ray'].nil? rescue nil
      read_mutex.synchronize{ print("#{query_uris.length} remaining\r") }
      set_mutex.synchronize { cloudflare_set.add(uri.host) } if cf_header_present
    end
  end
end.each(&:join); nil

p cloudflare_set.to_a.sort

@lbeltrame Happened to me as well with a different URL. I think its the _ in the url. I just searched for the problem domain in my chrome history, deleted it, and then the script ran fine.

For those who simply want to check their history or whatever tables are in your chrome history database, I created a small shell script to generate those files.

https://github.com/darrentu/convert-db-to-csv

On Linux, I had to switch the path to this:

chrome_history_location = "#{ENV['HOME']}/.config/google-chrome/Default/History"

See Chrome/Chromium User Data Directories