Upstart task generated by foreman doesn't find file? - ruby-on-rails

Question

I used foreman to export my Procfile to an upstart task.
Procfile:
web: bundle exec rails server
websocket: bundle exec rails runner websocket-server/em_websocket.rb
One of the upstart tasks (they are very alike and fail with the same error):
start on starting app-web
stop on stopping app-web
respawn
env PORT=5000
setuid app
chdir /var/www/app
exec bundle exec rails server
And the error (I got it via dmesg):
[35207.676836] init: Failed to spawn app-websocket-1 main process: unable to execute: No such file or directory
[35207.679577] init: Failed to spawn app-web-1 main process: unable to execute: No such file or directory
When I switch to the app user, I am actually able to run bundle exec rails server from the given directory.
Is there any way to pin down the error a little more? I didn't find any related logs in /var/log/upstart/.

Answer 1

If you installed ruby via RVM it may be possible that the init is run before the rvm script runs. Did you try using absolute references to the bundle bin?
whereis bundle
to obtain it
RVM was apparently not initialized or is not available in the upstart enviroment. Luckily rvm has wrappers for this case: https://rvm.io/integration/init-d

Answer 2

You can run bundle in another way.
Instead of:
web: bundle exec rails server
You need to run:
web: bash -c '~/.rvm/bin/rvm default do bundle exec rails server'
Note: ~/.rvm/bin/rvm - can be replaced with actual path of rvm installation on your server.

Answer 3

Upstart commands require sudo privileges for the underlying user. Have you considered defining some form of passwordless sudo privileges for your app user to run the rails application service restarts?
e.g In Ubuntu creating a new sudoer definition under /etc/sudoers.d/?
username ALL=(ALL) NOPASSWD:ALL
Once defined 'username' should be able to run the rails app via sudo service 'appname' stop|start|restart.
Here is an explanation for providing the sudo privileges to the user. My Capistrano deployment contains a foreman export definition as below -
namespace :foreman do
desc 'Export the Procfile to Ubuntu upstart scripts'
task :export do
on roles(:app) do |host|
log_path = shared_path.join('log')
within release_path do
execute :mv, ".env .envbkup"
execute :echo, "'RACK_ENV=#{fetch(:deploy_env)}' >> .env"
execute :echo, "'RAILS_ENV=#{fetch(:deploy_env)}' >> .env"
execute :bundle, "exec foreman export upstart #{shared_path}/init -a #{fetch(:application)} -u #{host.user} -l #{log_path}"
execute :rm, ".env"
execute :mv, ".envbkup .env"
as :root do
execute :cp, "#{shared_path}/init/* /etc/init/"
end
end
end
end
This capistrano definition is invoked from the deploy_env.rb 'after' action.