memcache-list-keys.rb

#!/usr/bin/env ruby
require 'net/telnet'

prefix = ARGV.length > 1 ? ARGV[1] : nil
prefix_regexp = prefix && Regexp.new("\A#{prefix}")

cache_dump_limit = 100
localhost = Net::Telnet::new("Host" => "localhost", "Port" => 11211, "Timeout" => 3)
slab_ids = []
localhost.cmd("String" => "stats items", "Match" => /^END/) do |c|
  matches = c.scan(/STAT items:(\d+):/)
  slab_ids = matches.flatten.uniq
end

cache_keys = []
slab_ids.each do |slab_id|
  localhost.cmd("String" => "stats cachedump #{slab_id} #{cache_dump_limit}", "Match" => /^END/) do |c|
    matches = c.scan(/^ITEM (.+?) \[(\d+) b; (\d+) s\]$/).each do |key_data|
      (cache_key, _, _) = key_data

      if cache_key =~ /\:session\:/i
        next
      elsif prefix_regexp && prefix_regexp.match(cache_key)
        cache_keys << cache_key
      else
        cache_keys << cache_key
      end
    end
  end
end

localhost.close

cache_keys.sort.each do |key|
  puts key
end