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End of Life Ruby 3.0 has reached end of life and gets no more fixes. Switch to Ruby 4.0 →

module · Ruby 3.0

SecureRandom

4 class methods

Secure random number generator interface.

This library is an interface to secure random number generators which are suitable for generating session keys in HTTP cookies, etc.

You can use this library in your application by requiring it:

Example

require 'securerandom'

It supports the following secure random number generators:

openssl
/dev/urandom
Win32

SecureRandom is extended by the Random::Formatter module which defines the following methods:

alphanumeric
base64
choose
gen_random
hex
rand
random_bytes
random_number
urlsafe_base64
uuid

These methods are usable as class methods of SecureRandom such as SecureRandom.hex.

Examples

Generate random hexadecimal strings:

Example

require 'securerandom'

SecureRandom.hex(10) #=> "52750b30ffbc7de3b362"
SecureRandom.hex(10) #=> "92b15d6c8dc4beb5f559"
SecureRandom.hex(13) #=> "39b290146bea6ce975c37cfc23"

Generate random base64 strings:

Example

SecureRandom.base64(10) #=> "EcmTPZwWRAozdA=="
SecureRandom.base64(10) #=> "KO1nIU+p9DKxGg=="
SecureRandom.base64(12) #=> "7kJSM/MzBJI+75j8"

Generate random binary strings:

Example

SecureRandom.random_bytes(10) #=> "\016\t{\370g\310pbr\301"
SecureRandom.random_bytes(10) #=> "\323U\030TO\234\357\020\a\337"

Generate alphanumeric strings:

Example

SecureRandom.alphanumeric(10) #=> "S8baxMJnPl"
SecureRandom.alphanumeric(10) #=> "aOxAg8BAJe"

Generate UUIDs:

Example

SecureRandom.uuid #=> "2d931510-d99f-494a-8c67-87feb05e1594"
SecureRandom.uuid #=> "bad85eb9-0713-4da7-8d36-07a8e4b00eab"

Class methods 4

.bytes .gen_random .gen_random_openssl .gen_random_urandom