Django Dumpdata Field

Custom dumpdata and loaddata commands that allow to export given fields of a model.

I know this is a really stupid usecase and no one should actually do this, but let's say you have a staging server where your authors create articles and maintain the content.

Then you have a production server and when you deploy the site, you actually export the database of the staging server and import it on the production server.

That's all good and easy until you have some apps that generate data, for example click statistics for links and files. You don't want to lose these stats when you import the database from the staging server.

This app aims to solve that issue.

1. On production: ./manage.py dumpdata_field app_name.ModelName fields=field1,field2 > output.json
2. Export the staging database and import it on the produciton server
3. On production: ./manage.py loaddata_field output.json

The loaddata command will iterate over all items in the JSON file and see if that PK still exists on the server. If so, it will load the object and ONLY change the given field and save the object.

Installation

To get the latest stable release from PyPi

pip install django-dumpdata-field

To get the latest commit from GitHub

pip install -e git+git://github.com/bitmazk/django-dumpdata-field.git#egg=dumpdata_field

TODO: Describe further installation steps (edit / remove the examples below):

Add dumpdata_field to your INSTALLED_APPS

INSTALLED_APPS = (
    ...,
    'dumpdata_field',
)

Usage

It's quite simple. First export your data like so:

./manage.py dumpdata_field app_name.ModelName fields=field1,field2,field3 > output.json

Then import your data like so:

./manage.py loaddata_field > output.json

Warning: If for some reason a primary key on staging was re-used, this app will of course not know about this. It will find the PK in the output file, load the object from the database and update the given fields. If this object is now a completely different object than it was before on the production server, you are out of luck. You have been warned.

Contribute

If you want to contribute to this project, please perform the following steps

# Fork this repository
# Clone your fork
mkvirtualenv -p python2.7 django-dumpdata-field
make develop

git co -b feature_branch master
# Implement your feature and tests
git add . && git commit
git push -u origin feature_branch
# Send us a pull request for your feature branch