I'm having the same issue as BB and others on newer versions of rails. Cards and lists are being created, but they only display on another browser upon refresh.
From the terminal, I can see that the commit is sent to action cable, but the payload is showing up as a crazy looking string that starts off with an html doctype (which seems to be be way off from the pretty json data it should be outputting).
I feel like the issue may stem from the board_channel.js file I have, since
console.log(data) (@13:15 in the video) doesn't even get fired. If anyone figures this one out, let me know! I've been banging my head against the wall for the better part of a day.
Posted in Rails credentials returning nil
I know this comment is quite a bit late, but I just ran into this same issue but on the Stripe course when adding my stripe keys to the credentials doc.
I kept getting the same error 'NoMethodError (undefined method ' for nil:NilClass)' even though in the rails console Rails.application.credentials.stripe[:public_key] seemed to be working swimmingly.
What worked for me was actually regenerating my master key & credentials file. Once I popped the credentials in there and restarted the server, it seemed to work.