Cannot pipe output from python command

Question

I am trying to backup a django app via the built in "dumpdata" command:

python manage.py dumpdata --exclude=contenttypes --indent=4 > path_to_dumped_data.json

But the json data is being printed to the screen and the file remains empty

Any ideas

(python2.6, django 1.2.3, Ubuntu 10.04 LTS)

dumpdata definitely prints to stdout by default. What happens when you run $ python manage.py dumpdata --exclude=contenttypes --indent=4 > /dev/null ? — David Miller
– David Miller, Commented Dec 6, 2010 at 16:18

Šimon Tóth · Accepted Answer · 2010-12-06 16:07:22Z

2

Try using &> or 2>. Although weird, the output might be printed to standard error output.

answered Dec 6, 2010 at 16:07

Šimon Tóth

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2 Comments

Just to check I ran this via the subprocess module - nothing went to stdout, everything to stderr with an error code of 0!

That seems like bad behavior to me. According to docs.djangoproject.com/en/dev/ref/django-admin/… dumpdata "Outputs to standard output" so that's clearly a bug. I've submitted a bug here: code.djangoproject.com/ticket/14847