decode base64 with dollar sign in ruby 1.8.5

Question

Hello,

I have base64-encoded string (with two dollar signs, so it's not a common base64 string)

The problem: Base64.decode64 (or .unpack("m")) decodes it just fine on my local machine(ruby 1.8.6), but with ruby 1.8.5 (the version used by Heroku) it doesn't work

Any ideas ?

edit:

I have :

$$YTo1OntzOjM6Im1pZCI7czo3OiI3MTE5Njg3IjtzOjQ6Im5hbWUiO3M6MjE6IkthbnllIFdlc3QgLSBTdHJvbmd lciI7czo0OiJsaW5rIjtzOjQ4OiJodHRwOi8vd3d3LmVhc3kxNS5jb20vMDIgU3Ryb25nZXIgKFNuaXBwZXQpMS5tcD MiO3M6OToiX3BsYXl0aW1lIjtzOjU6IjgzMjAwIjtzOjg6Il9uZXh0aWRzIjtzOjEzNDoiMjc1ODE0MDYsMjc0MDE1 NzAsMjI1MTU0MDMsMTU1ODM2NjYsMTYzMTUzMzksMjgwNDY5MTUsMzAzOTMxODksMzUyMDAyMTMsMjIwNTE1MzAsMj c1NTg1MTQsMTM3ODkyNTYsMTk4MTY5OTgsMzA0NzI4MDEsMTUyNTk5NzksMTg5OTkxMzciO30=

I successed in decoding it with '...'.unpack("m") locally but not on the heroku server (ruby 1.8.5, maybe the ruby version it's not the issue)

Answer 1

@Gumbo

I have :

$$YTo1OntzOjM6Im1pZCI7czo3OiI3MTE5Njg3IjtzOjQ6Im5hbWUiO3M6MjE6IkthbnllIFdlc3QgLSBTdHJvbmdlciI7czo0OiJsaW5rIjtzOjQ4OiJodHRwOi8vd3d3LmVhc3kxNS5jb20vMDIgU3Ryb25nZXIgKFNuaXBwZXQpMS5tcDMiO3M6OToiX3BsYXl0aW1lIjtzOjU6IjgzMjAwIjtzOjg6Il9uZXh0aWRzIjtzOjEzNDoiMjc1ODE0MDYsMjc0MDE1NzAsMjI1MTU0MDMsMTU1ODM2NjYsMTYzMTUzMzksMjgwNDY5MTUsMzAzOTMxODksMzUyMDAyMTMsMjIwNTE1MzAsMjc1NTg1MTQsMTM3ODkyNTYsMTk4MTY5OTgsMzA0NzI4MDEsMTUyNTk5NzksMTg5OTkxMzciO30=

I successed in decoding it with '...'.unpack("m") locally but not on the heroku server (ruby 1.8.5, maybe the ruby version it's not the issue)

Answer 2

The dollar sign is not part of the Base64 specification.

Simply strip the leading $$ before unpacking:

str.sub(/^\$*/, '').unpack('m')

To strip all non-Base64 characters, emulating new (Ruby 1.8.6) behaviour,

str.gsub(/[^ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789\+\/]/, '').unpack('m')

Ruby 1.8.6 will ignore all non-Base64 symbols (including the $) inside the string to decode, whereas 1.8.5 will stop processing at the first such character (see pack.c in the Ruby source.)

Cheers, V.