[Duplicity-talk] Duplicity-GPG connection fails

[Scott Hannahs]

I am trying to get duplicity to run periodically without user intervention like 
a good backup system.  This is duplicity v 0.6.06 and Mac OS X so I am using 
the launchd system.

Each night I get a slightly different output
Warning, found the following orphaned backup files:
[duplicity-inc.20091128T215134Z.to.20091130T034509Z.manifest.gpg]
[duplicity-inc.20091130T034509Z.to.20091203T001312Z.manifest.gpg, 
duplicity-inc.20091130T034509Z.to.20091203T001312Z.vol1.difftar.gpg, 
duplicity-inc.20091130T034509Z.to.20091203T001312Z.vol2.difftar.gpg]
[duplicity-inc.20091203T001312Z.to.20091203T030248Z.manifest.gpg, 
duplicity-inc.20091203T001312Z.to.20091203T030248Z.vol1.difftar.gpg]
Last full backup date: none
No signatures found, switching to full backup.

and the error output is:
GPGError: GPG Failed, see log below:
===== Begin GnuPG log =====
usage: gpg [options] [filename]
===== End GnuPG log =====

The same duplicity command runs correctly from the command line.
This seems to indicate that I am not getting some environment variable set.  
This command is running without running a shell other than python.

Here is the effective command that I am running each night:
PATH=/sw/bin:/sw/sbin:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin 
PYTHONPATH=/sw/lib:/Library/Python  PASSPHRASE="" HOME=/Users/sth 
/usr/local/bin/duplicity --encrypt-key XXXXXXXX --sign-key YYYYYYYY 
--gpg-options='--default-key=XXXXXXXX' /Users/sth/Documents 
file:///tmp/Documents/

Does duplicity need any other environment variables?  How does it find either 
the .gnupg options or the .cache files?  The error logs don't seem to be 
helpful as to why gpg is unhappy.  If it is launched without a shell other than 
python is that a problem?  I am using gpg version 1.4.10 and gpg2 is version 
2.0.9.  Should I be telling duplicity to use gpg2 instead of gpg?


Any hints as to where to start probing for finding the cause of this error 
would be appreciated.

-sth