randomstring sample

bench_randomstring.rb

#!/usr/bin/env ruby

require 'securerandom'
require 'openssl'
require 'base62' # base62 gem

require 'benchmark'

module RandomString
  class Concat
    def initialize(length = 8)
      @length = length
      @str=[*('a'..'z'),*('A'..'Z'),*('0'..'9')]
    end
    def randomstring
      "".tap{|result| @length.times{ result << @str[rand(@str.size)] } }
    end
  end

  class Join
    def initialize(length = 8)
      @length = length
      @str=[*('a'..'z'),*('A'..'Z'),*('0'..'9')]
    end
    def randomstring
      Array.new(@length){ @str[rand(@str.size)] }.join
    end
  end

  class SecureRandom
    def initialize(length = 8)
      @length = length
      @randomlength = (length/4.0).ceil * 3
    end
    def randomstring
      ::SecureRandom.base64(@randomlength)
    end
  end

  class OpenSSL
    def initialize(length = 8)
      @length = length
      @randomlength = (length/4.0).ceil * 3
    end
    def randomstring
      [::OpenSSL::Random.random_bytes(@randomlength)].pack('m')
    end
  end

  class Base62
    def initialize(length = 8)
      @length = length
      @max = 62**length
      @min = 62**(length-1)
      @size = @max - @min
    end
    def randomstring(length = 8)
      (::Random.rand(@size)+@min).base62_encode
    end
  end
end

n = 300000

[8,16,32].each do |length|

  concat  = RandomString::Concat.new(length)
  join    = RandomString::Join.new(length)
  sran    = RandomString::SecureRandom.new(length)
  openssl = RandomString::OpenSSL.new(length)
  b62     = RandomString::Base62.new(length)

  puts
  puts "sample(#{length})>"
  puts "concat  => #{concat.randomstring}"
  puts "join    => #{join.randomstring}"
  puts "sran    => #{sran.randomstring}"
  puts "openssl => #{openssl.randomstring}"
  puts "b62     => #{b62.randomstring}"
  puts 

  Benchmark.bm {|x|
    x.report("concat  "){ n.times{concat.randomstring} }
    x.report("join    "){ n.times{join.randomstring} }
    x.report("sran    "){ n.times{sran.randomstring} }
    x.report("openssl "){ n.times{openssl.randomstring} }
    x.report("b62     "){ n.times{b62.randomstring} }
  }

end

=begin


sample(8)>
concat  => 9lEhDm4X
join    => LroYhrnZ
sran    => XJQuK0bJ
openssl => nJFmqu9W
b62     => weI7rNgw

      user     system      total        real
concat    1.140000   0.000000   1.140000 (  1.147652)
join      1.570000   0.030000   1.600000 (  1.588756)
sran      2.310000   0.000000   2.310000 (  2.315751)
openssl   1.270000   0.020000   1.290000 (  1.280817)
b62       1.300000   0.000000   1.300000 (  1.304127)

sample(16)>
concat  => rGmYvuCPyW6RTMVR
join    => fcKvLoizHjZaraHk
sran    => 93ncqITQzDfwTvAT
openssl => uIRa/vlG4wtziVSg
b62     => BVtZEVmjpuROSyLj

      user     system      total        real
concat    2.050000   0.000000   2.050000 (  2.058186)
join      2.600000   0.040000   2.640000 (  2.638252)
sran      2.510000   0.010000   2.520000 (  2.506866)
openssl   1.450000   0.010000   1.460000 (  1.461524)
b62       5.290000   0.010000   5.300000 (  5.300914)

sample(32)>
concat  => IUyEjRJkl1jJGBBQbsd9OqFlOriMvSlw
join    => z9Nka1tRDFsm29bLfsDYFWuM2FCb9gJX
sran    => O/LsNKer4LvFo/nknkFz1U1JkLRA6aRx
openssl => BOvctaodQG2hvRr94G9plvWVck9yZkVO
b62     => rdxQ9HabP9m9Z2a1WpC7LcmLSQJNEGWx

      user     system      total        real
concat    4.010000   0.010000   4.020000 (  4.018792)
join      4.580000   0.080000   4.660000 (  4.658750)
sran      3.020000   0.010000   3.030000 (  3.021287)
openssl   1.790000   0.010000   1.800000 (  1.805106)
b62      16.000000   0.050000  16.050000 ( 16.106021)

=end