parse.rb

def parse_csv(file)
  uuid_lookup = {}
  parsed_rows = 0
 
  print "Opening CSV ..."
  Zlib::GzipReader.open(file) do |csv|
    puts "DONE"
    print "Preparing to parse CSV ..."
    CSV.parse(csv.read, headers: true) do |row|
      if parsed_rows == 0
        puts "READY!"
        puts "Parsing rows..."
      end
 
      begin
        uuid_lookup[row['Id']] = UUIDTools::UUID.parse(row['Deal_UUID__c']).raw
      rescue ArgumentError
        puts "Ignoring invalid UUID"
      end
      parsed_rows += 1
      puts "Parsed #{parsed_rows} rows" if 0 == (parsed_rows % 10_000)
    end
  end
 
  uuid_lookup
end

uuid_lookup('/var/tmp/sf_uuid_lookup.csv.gz'); nil