local variable 'rtd' referenced before assignment

[Jason Hobbs]

Hit this bug trying to run a network_command via curtin:

root@cylindrical-joke:~/curtin# 'curtin' --showtrace 'install' '--config=configs/config-000.cfg' 'http://192.168.0.25/MAAS/static/images/ubuntu/amd64/generic/trusty/daily/root-tgz'
Traceback (most recent call last):
  File "/root/curtin/curtin/commands/main.py", line 96, in main
    sys.exit(args.func(args))
  File "/root/curtin/curtin/commands/in_target.py", line 61, in in_target_main
    with util.ChrootableTarget(target, allow_daemons=args.allow_daemons):
  File "/root/curtin/curtin/util.py", line 301, in __enter__
    if rtd:
UnboundLocalError: local variable 'rtd' referenced before assignment
local variable 'rtd' referenced before assignment
Traceback (most recent call last):
  File "/root/curtin/curtin/commands/main.py", line 96, in main
    sys.exit(args.func(args))
  File "/root/curtin/curtin/commands/install.py", line 267, in cmd_install
    stage.run()
  File "/root/curtin/curtin/commands/install.py", line 104, in run
    util.subp(cmd, shell=shell, env=self.env)
  File "/root/curtin/curtin/util.py", line 68, in subp
    cmd=args)
ProcessExecutionError: Unexpected error while running command.
Command: curtin in-target -- apt-get --assume-yes install bridge-utils
Exit code: 3

Turns out the tempfile.mkdtemp call that is suppose to set rtd is failing in this case, so rtd is never created, and when it's referenced in the except handler, we get the stacktrace above instead of something useful.

[Scott Moser (smoser)]

This bug is believed to be fixed in curtin in 17.1. If this is still a problem for you, please make a comment and set the state back to New

Thank you.