Archive for 12th August 2008

Google App Engine Rolling Back an Update

If you had an App Engine update go awry, you may need to roll it back. You will get a message like this when things are messed up and you try to “Deploy Application”:

*** Running appfg.py with the following flags:
--no_cookies --email=acct@gmail.com --passin update
Password for acct@gmail.com: Scanning files on local disk.
Initiating update.
2008-08-12 08:51:32,117 ERROR appcfg.py:1334 An unexpected error occurred. Aborting.
Error 409: --- begin server output ---
Another transaction by user acct is already in progress for this app and major version. That user can undo the transaction with appcfg.py's "rollback" command.
--- end server output ---
If deploy fails you might need to 'rollback' manually.
The "Make Symlinks..." menu option can help with command-line work.
*** appcfg.py has finished with exit code 0 ***

The solution (paths from a mac) is to running the command:

python /usr/local/bin/appcfg.py -verbose --no_cookies --email=acct@gmail.com --passin rollback simplelti

“simplelti” is the application directory – you need to run this where your application is a subdirectory.