How do I get the path for the release being deployed in Capistrano 3? - capistrano3

Question

During my deploy process, I need to create a symbolic link to the correct version of a configuration file, which depends on the environment. While I expected that to be trivial, I could not find anywhere how to get the current path.
I need to operate on the release directory before the current symbolic link is switched to it. release_path yields the path to the current directory, rather than something like releases/20170131090326/.
namespace :deploy do
desc 'Link daemon configuration file'
task :link_daemon_config do
on roles(:batch) do
execute "ln -s #{release_path}/app/config/daemon_prod.config #{release_path}/app/config/daemon.config"
end
end
after :updated, :link_daemon_config
end
I do have ideas for a workaround; the question is just about how could I refer to the current directory and where can I find information like this in the future.
Thank you

Answer 1

I managed to solve this in a similar use-case. Make sure keep-releases is set to a number higher than 2. e.g set :keep_releases, 3
Try this:
namespace :deploy do
desc 'Link daemon configuration file'
task :link_daemon_config do
on roles(:batch) do
last_release = capture(:ls, "-xt", releases_path).split[1]
last_release_path = releases_path.join(last_release)
execute "ln -s #{last_release_path}/app/config/daemon_prod.config #{release_path}/app/config/daemon.config"
end
end
after :updated, :link_daemon_config
end
Useful links: https://github.com/capistrano/capistrano/blob/master/lib/capistrano/tasks/deploy.rake#L184
Similar topic: https://stackoverflow.com/a/26267220/15500541