I am using this library for sessions.
https://github.com/codegangsta/martini-contrib/tree/master/sessions
It says that:
It is recommended to use an authentication key with 32 or 64 bytes. The encryption key, if set, must be either 16, 24, or 32 bytes to select AES-128, AES-192, or AES-256 modes.
How do I generate a 64 byte key, is it as straightforward as []byte"64characterslongstring"
, I thought it is not always so straight forward?