Trouble with ActiveSupport::MessageEncryptor::InvalidMessage in plugin

[pfaffman (Jay Pfaffman)]

Thanks, @gerhard!

So at Upgrading Ruby on Rails — Ruby on Rails Guides

I find

As of Rails 7.1, the default serializer in use by the MessageEncryptor is JSON. This offers a more secure alternative to the current default serializer.

The MessageEncryptor offers the ability to migrate the default serializer from Marshal to JSON.
If you would like to ignore this change in existing applications, set the following: config.active_support.default_message_encryptor_serializer = :marshal .

(but that says Rails 7.1?)

Is there some way that you know off the top of your head that I can ignore this change in my existing plugin with some obvious-once-you-know-it line in my plugin.rb?

Or maybe I’m going to have to figure out what this means.

EDIT: but on dev adding that line to config/application.rb is not a magic fix.

Sorry. I read a bit further:

3.10 Key generator digest class changing to use SHA256

The default digest class for the key generator is changing from SHA1 to SHA256. This has consequences in any encrypted message generated by Rails, including encrypted cookies.

In order to be able to read messages using the old digest class it is necessary to register a rotator.

So maybe that will solve my immediate problem. Thanks again for your help! Maybe I’ll get it this time.

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Well, the key I generate for both rails 6 and rails 7 looks like this:

#<ActiveSupport::KeyGenerator:0x000055870212d4f8 @hash_digest_class=OpenSSL::Digest::SHA1, @iterations=65536, @secret="my-big-secret">

but they encrypt things differently. I was hoping that the hash_digest_class was the issue, but it at least looks like it’s the same on both, but the encrypted string is different.