SecureRandom.alphanumeric generates a random alphanumeric string.
The argument n specifies the length, in characters, of the alphanumeric string to be generated.
If n is not specified or is nil, 16 is assumed. It may be larger in the future.
The result may contain A-Z, a-z and 0-9.
require 'securerandom' SecureRandom.alphanumeric #=> "2BuBuLf3WfSKyQbR" SecureRandom.alphanumeric(10) #=> "i6K93NdqiH"
If a secure random number generator is not available, NotImplementedError
is raised.
# File securerandom.rb, line 310 def alphanumeric(n=nil) n = 16 if n.nil? choose(ALPHANUMERIC, n) end
SecureRandom.base64 generates a random base64 string.
The argument n specifies the length, in bytes, of the random number to be generated. The length of the result string is about 4/3 of n.
If n is not specified or is nil, 16 is assumed. It may be larger in the future.
The result may contain A-Z, a-z, 0-9, “+”, “/” and “=”.
require 'securerandom' SecureRandom.base64 #=> "/2BuBuLf3+WfSKyQbRcc/A==" SecureRandom.base64 #=> "6BbW0pxO0YENxn38HMUbcQ=="
If a secure random number generator is not available, NotImplementedError
is raised.
See RFC 3548 for the definition of base64.
# File securerandom.rb, line 181 def base64(n=nil) [random_bytes(n)].pack("m0") end
SecureRandom.hex generates a random hexadecimal string.
The argument n specifies the length, in bytes, of the random number to be generated. The length of the resulting hexadecimal string is twice of n.
If n is not specified or is nil, 16 is assumed. It may be larger in the future.
The result may contain 0-9 and a-f.
require 'securerandom' SecureRandom.hex #=> "eb693ec8252cd630102fd0d0fb7c3485" SecureRandom.hex #=> "91dc3bfb4de5b11d029d376634589b61"
If a secure random number generator is not available, NotImplementedError
is raised.
# File securerandom.rb, line 158 def hex(n=nil) random_bytes(n).unpack("H*")[0] end
SecureRandom.random_bytes generates a random binary string.
The argument n specifies the length of the result string.
If n is not specified or is nil, 16 is assumed. It may be larger in future.
The result may contain any byte: “x00” - “xff”.
require 'securerandom' SecureRandom.random_bytes #=> "\xD8\\\xE0\xF4\r\xB2\xFC*WM\xFF\x83\x18\xF45\xB6" SecureRandom.random_bytes #=> "m\xDC\xFC/\a\x00Uf\xB2\xB2P\xBD\xFF6S\x97"
If a secure random number generator is not available, NotImplementedError
is raised.
# File securerandom.rb, line 136 def random_bytes(n=nil) n = n ? n.to_int : 16 gen_random(n) end
SecureRandom.urlsafe_base64 generates a random URL-safe base64 string.
The argument n specifies the length, in bytes, of the random number to be generated. The length of the result string is about 4/3 of n.
If n is not specified or is nil, 16 is assumed. It may be larger in the future.
The boolean argument padding specifies the padding. If it is false or nil, padding is not generated. Otherwise padding is generated. By default, padding is not generated because “=” may be used as a URL delimiter.
The result may contain A-Z, a-z, 0-9, “-” and “_”. “=” is also used if padding is true.
require 'securerandom' SecureRandom.urlsafe_base64 #=> "b4GOKm4pOYU_-BOXcrUGDg" SecureRandom.urlsafe_base64 #=> "UZLdOkzop70Ddx-IJR0ABg" SecureRandom.urlsafe_base64(nil, true) #=> "i0XQ-7gglIsHGV2_BNPrdQ==" SecureRandom.urlsafe_base64(nil, true) #=> "-M8rLhr7JEpJlqFGUMmOxg=="
If a secure random number generator is not available, NotImplementedError
is raised.
See RFC 3548 for the definition of URL-safe base64.
# File securerandom.rb, line 213 def urlsafe_base64(n=nil, padding=false) s = [random_bytes(n)].pack("m0") s.tr!("+/", "-_") s.delete!("=") unless padding s end
SecureRandom.uuid generates a random v4 UUID (Universally Unique IDentifier).
require 'securerandom' SecureRandom.uuid #=> "2d931510-d99f-494a-8c67-87feb05e1594" SecureRandom.uuid #=> "bad85eb9-0713-4da7-8d36-07a8e4b00eab" SecureRandom.uuid #=> "62936e70-1815-439b-bf89-8492855a7e6b"
The version 4 UUID is purely random (except the version). It doesn't contain meaningful information such as MAC addresses, timestamps, etc.
The result contains 122 random bits (15.25 random bytes).
See RFC 4122 for details of UUID.
# File securerandom.rb, line 235 def uuid ary = random_bytes(16).unpack("NnnnnN") ary[2] = (ary[2] & 0x0fff) | 0x4000 ary[3] = (ary[3] & 0x3fff) | 0x8000 "%08x-%04x-%04x-%04x-%04x%08x" % ary end