capistrano - shared_config bug

[dazza-codes]

I have some thoughts/concerns around this capistrano practice, as a result of the SDR-PC problems this week, see

• https://github.com/sul-dlss/sdr-preservation-core/blob/master/config/deploy.rb#L59-L60

• the old-config is probably required to shutdown robots and any “restart” process is usually two or three steps: stop, quit, boot

  • for the stop phase, the old configs, esp. the robot_{stage}.yml file, is required to shutdown and de-register the robots (right?)
  • https://github.com/sul-dlss/robot-controller/blob/master/lib/robot-controller/robots.rb#L81
  • if so, updating the configs before the entire restart could wipe out the old record of the robot definitions (if they are changed)
  • perhaps the config update should happen after the stop phase of the restart

• there is no provision for a rollback of the config changes if the restart fails