ActiveSupport::MessageEncryptorを慎重に使う

経緯

Rubyを2.3系から2.4.1に上げたら、ActiveSupport::MessageEncryptorを使っているところが壊れた。ちなみにRailsは5.0.1。

key must be 32 bytes
/Users/nisshiee/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/activesupport-5.0.1/lib/active_support/message_encryptor.rb:79:in `key='
/Users/nisshiee/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/activesupport-5.0.1/lib/active_support/message_encryptor.rb:79:in `_encrypt'
/Users/nisshiee/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/activesupport-5.0.1/lib/active_support/message_encryptor.rb:60:in `encrypt_and_sign'
...
続きを読む