How to close connection in Action cable?

Disconnecting from the client

I stumbled across this issue too. But I could not believe that there is no simple way to disconnect the websocket connection from the client (without doing an API call). Luckily this works for me:

// Create consumer
window.cable = ActionCable.createConsumer(...)

// Subscribe to channels
window.cable.subscriptions.create('SomeChannel', ...);

// At some point we want to disconnect (e.g. when user logs out)
window.cable.subscriptions.consumer.disconnect();

Disconnecting a client from your rails application

If you want to disconnect a client from the rails application, use the disconnect method as described in the documentation: https://api.rubyonrails.org/classes/ActionCable/RemoteConnections.html

module ApplicationCable
  class Connection < ActionCable::Connection::Base
    identified_by :current_user
    ....
  end
end

ActionCable.server.remote_connections.where(current_user: User.find(1)).disconnect

Disconnecting from the client side

If you want to disconnect the user from the client side you can use the disconnect and unsubscribe functions in your javascript:

App.cable = ActionCable.createConsumer(...)

// Closes the websocket connection.
App.cable.disconnect();

// Unsubscribe from a actioncable subscription (without disconnecting the websocket connection)
App.example = App.cable.subscriptions.create(..);
App.example.unsubscribe();

I found this inside /var/lib/gems/2.3.0/gems/actioncable-5.0.1/lib/action_cable/remote_connections.rb

If you need to disconnect a given connection, you can go through the RemoteConnections. You can find the connections you're looking for by searching for the identifier declared on the connection. For example:

module ApplicationCable
  class Connection < ActionCable::Connection::Base
    identified_by :current_user
    ....
  end
end

ActionCable.server.remote_connections.where(current_user: User.find(1)).disconnect

This will disconnect all the connections established for
User.find(1), across all servers running on all machines, because it uses the internal channel that all of these servers are subscribed to.

Hope this will be useful. Looks like it works even in Rails console.