React and Action Cable

Currently, our concert show page makes a fetch call to the server to determine the current status of the seats on the page, and it makes a POST call to put a seat on hold after you click on it. We can replace both of these calls with a single Action Cable subscription. Granting, of course, that this is an absurdly minimalist implementation, since we’re not dealing with user logins or complicated state transitions or anything like that.

ConcertChannel on the server

On the server-side, we need to create a new Action Cable channel. This one will have the same subscribe method as our previous channel, but we need to add a method for our client-side to call to actually reserve a ticket: