Equivalent of `run command, once: true` in Capistrano 3

[Joshua Wood]

Capistrano 2 used to have an option to run a command once on a remote server rather than on all roles (I believe this was the `run 'command', once: true` option?). Does Capistrano 3/SSHKit have a similar option?

[Lee Hambley]

Just do:

on roles(:role_with_one_server) do 

# or

on 'example.com' do 

  execute(anything)

end

That'll do it. No need for a special DSL.