Upstart bash completion does not work on ubuntu server

[Davor Cubranic]

Natty server does not install the dbus daemon, but upstart's bash completion script (/etc/bash_completion.d/upstart) depends on it to be running. Therefore, typing:

$ sudo restart <tab>

will output the following error message:
initctl: Unable to connect to system bus: Failed to connect to socket /var/run/dbus/system_bus_socket: No such file or directory

[James Hunt (jamesodhunt)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. However, this issue is caused by the fact that a default natty server does not install the "dbus" package and hence non-root users are unable to communicate with Upstart using initctl (specifically the "list" and "status" commands will not work).

So, to resolve your issue, there are 2 main choices:

- Use a full root shell such that tab completion will work.
  ("su -" or "sudo su -" and then initctl tab completion will work.

- install the dbus package ("sudo apt-get install dbus").

  Non-root users will then be able to invoke initctl.

Clearly, you need to be aware of the implications of adopting either of these choices.

[Davor Cubranic (cubranic)]

James, your explanation for why this report is invalid just restated my bug description.

The bug precisely is that Ubuntu is shipping a package (upstart's bash completion) with an implicit dependency on another package (dbus) that it does not declare! So if the developers view this dependency as optional, then the upstart package should: 1) declare dbus as suggested; and 2) not throw an error in the completion function if dbus is not running but fail gracefully and degrade to not completing anything instead of dumping errors to console.

[Dimitri John Ledkov (xnox)]

but bash_completion is optional functionality that is not guaranteed to work, e.g. upstart doesn't declare dependency on bash either.

Returning nothing in completion would be also confusing (nothing available to restart) and failing loud at runtime (by printing errors) is acceptable to let user know that something is wrong.

upstart package is not going to get dependency on "dbus" package. And bash-completion is Suggests already.