Module: Base64
Relationships & Source Files | |
Defined in: | lib/base64.rb |
Overview
The Base64 module provides for the encoding (#encode64, #strict_encode64, #urlsafe_encode64) and decoding (#decode64, #strict_decode64, #urlsafe_decode64) of binary data using a Base64
representation.
Example
A simple encoding and decoding.
require "base64"
enc = Base64.encode64('Send reinforcements')
# -> "U2VuZCByZWluZm9yY2VtZW50cw==\n"
plain = Base64.decode64(enc)
# -> "Send reinforcements"
The purpose of using base64 to encode data is that it translates any binary data into purely printable characters.
Class Method Summary
-
.decode64(str)
mod_func
Returns the Base64-decoded version of
str
. -
.encode64(bin)
mod_func
Returns the Base64-encoded version of
bin
. -
.strict_decode64(str)
mod_func
Returns the Base64-decoded version of
str
. -
.strict_encode64(bin)
mod_func
Returns the Base64-encoded version of
bin
. -
.urlsafe_decode64(str)
mod_func
Returns the Base64-decoded version of
str
. -
.urlsafe_encode64(bin, padding: true)
mod_func
Returns the Base64-encoded version of
bin
.
Class Method Details
.decode64(str) (mod_func)
Returns the Base64-decoded version of str
. This method complies with RFC 2045. Characters outside the base alphabet are ignored.
require 'base64'
str = 'VGhpcyBpcyBsaW5lIG9uZQpUaGlzIG' +
'lzIGxpbmUgdHdvClRoaXMgaXMgbGlu' +
'ZSB0aHJlZQpBbmQgc28gb24uLi4K'
puts Base64.decode64(str)
Generates:
This is line one
This is line two
This is line three
And so on...
# File 'lib/base64.rb', line 58
def decode64(str) str.unpack("m").first end
.encode64(bin) (mod_func)
Returns the Base64-encoded version of bin
. This method complies with RFC 2045. Line feeds are added to every 60 encoded characters.
require 'base64'
Base64.encode64("Now is the time for all good coders\nto learn Ruby")
Generates:
Tm93IGlzIHRoZSB0aW1lIGZvciBhbGwgZ29vZCBjb2RlcnMKdG8gbGVhcm4g
UnVieQ==
# File 'lib/base64.rb', line 38
def encode64(bin) [bin].pack("m") end
.strict_decode64(str) (mod_func)
Returns the Base64-decoded version of str
. This method complies with RFC 4648. ArgumentError is raised if str
is incorrectly padded or contains non-alphabet characters. Note that CR or LF are also rejected.
# File 'lib/base64.rb', line 73
def strict_decode64(str) str.unpack("m0").first end
.strict_encode64(bin) (mod_func)
Returns the Base64-encoded version of bin
. This method complies with RFC 4648. No line feeds are added.
# File 'lib/base64.rb', line 65
def strict_encode64(bin) [bin].pack("m0") end
.urlsafe_decode64(str) (mod_func)
Returns the Base64-decoded version of str
. This method complies with “Base 64 Encoding with URL and Filename Safe Alphabet'' in RFC 4648. The alphabet uses '-' instead of '+' and '_' instead of '/'.
The padding character is optional. This method accepts both correctly-padded and unpadded input. Note that it still rejects incorrectly-padded input.
# File 'lib/base64.rb', line 97
def urlsafe_decode64(str) # NOTE: RFC 4648 does say nothing about unpadded input, but says that # "the excess pad characters MAY also be ignored", so it is inferred that # unpadded input is also acceptable. str = str.tr("-_", "+/") if !str.end_with?("=") && str.length % 4 != 0 str = str.ljust((str.length + 3) & ~3, "=") end strict_decode64(str) end
.urlsafe_encode64(bin, padding: true) (mod_func)
Returns the Base64-encoded version of bin
. This method complies with “Base 64 Encoding with URL and Filename Safe Alphabet'' in RFC 4648. The alphabet uses '-' instead of '+' and '_' instead of '/'. Note that the result can still contain '='. You can remove the padding by setting padding
as false.
# File 'lib/base64.rb', line 83
def urlsafe_encode64(bin, padding: true) str = strict_encode64(bin).tr("+/", "-_") str = str.delete("=") unless padding str end