loaddata fails if models directory instead of models.py

[Phil Davis]

If the models for an app have been split into multiple files within a models subdirectory of the app then loaddata looks for fixtures in appname/models/fixtures instead of appname/fixtures.

To reproduce:

   django-admin.py startproject proj1
   cd proj1
   django-admin.py startapp foo
   cd foo
   vi ../settings.py  # set INSTALLED_APPS to just proj1.foo
   mkdir fixtures
   touch fixtures/abc.json

   ../manage.py loaddata --verbosity=2 abc.json
   Problem installing fixture '/data/home/leotest/projects/proj1/../proj1/foo/fixtures/abc.json': No JSON object could be decoded
   # location is correct, error is because file is empty

   rm models.py
   mkdir models
   touch models/__init__.py
   ../manage.py loaddata --verbosity=2 abc.json

   Loading 'abc' fixtures...
   Checking '/data/home/leotest/projects/proj1/../proj1/foo/models/fixtures' for fixtures...
   Trying '/data/home/leotest/projects/proj1/../proj1/foo/models/fixtures' for json fixture      'abc'...
   No json fixture 'abc' in '/data/home/leotest/projects/proj1/../proj1/foo/models/fixtures'.
   Checking absolute path for fixtures...
   Trying absolute path for json fixture 'abc'...
   No json fixture 'abc' in absolute path.
   No fixtures found.

The problem is that loaddata uses app.__file__ and app object is actually the app.models
module rather than the app module. This is around line 141 in core/management/commands/loaddata.py.

Note that setting app_label in Meta subclass for each model has no bearing on this problem.

[Phil Davis]

patch to make loaddata use app dir and not models module dir

[Phil Davis]

The attached patch (patch1) is against r7403 and tested on Linux. Not sure if it would work on windows.

[Jeff Anderson]

This definitely seems like a bug.

[zhaoz]

What is the status of this bug? I recently bumped into this issue, it looks like it hasn't been touched for quite awhile.

What needs to be done?

[zhaoz]

needs init.py file in loaddata folder. Tests fixture loading with models folder as opposed to models.py

[zhaoz]

The patch did not work for me when patched against svn trunk's 9222, failed test.

[zhaoz]

Replying to zhaoz:

The patch did not work for me when patched against svn trunk's 9222, failed test.

Scratch what I last said, it's working, but it doesn't seem to be done in a very elegant way.

[Michael Malone]

Seems what we're really trying to do here is determine whether the models module (return by get_apps()) is a package (a directory with an __init__.py and submodules) or a normal module. According to
​an essay that was published when package support landed in Python, the only difference between a package and an ordinary module is that a package has a __path__ attribute. Handily enough, the __path__ attribute is an array that, by default, contains a single string pointing to the package directory, which is at the equivalent level in the file system directory hierarchy as models.py.

I've attached a patch that checks the modules for the existence of a __path__ attribute and handles them properly (and another patch containing some tests). I'm fairly confident this is the right way to do this, given the essay linked to above. I think this method may also be used to remove the Meta.app_label requirement for models submodules.

[Michael Malone]

Patch that checks whether models module is a package by checking for path attribute

[Michael Malone]

Tests for patch 2

[HuCy]

Another approach. Found this Ticket too late, so i did a patch by myself.

[Stephane Raimbault]

I'm not sure if it's related to this bug but the loaddata command works only if there's a models.py file (empty) in the app directory:

That doesn't work:

app/__init__.py
    fixtures/data.json

that works:

app/__init__.py
    models.py
    fixtures/data.json

and the documentation says (or I didn't find) nothing about that requirement.
Tested with trunk r11032.

[Justin Lilly]

Patch looks good, applied cleanly. I've combined the tests for patch3 and patch3 into this patch.

[Justin Lilly]

patch 3 combined with tests.

[Luke Plant]

(In [11914]) Fixed #6961 - loaddata fails if models is a package instead of a module

Thanks to pmd for report, zhaoz, mmalone and justinlilly for patch

[Luke Plant]

(In [11918]) [1.1.X] Fixed #6961 - loaddata fails if models is a package instead of a module

Thanks to pmd for report, zhaoz, mmalone and justinlilly for patch

Backport of 11914 from trunk.

[xcco3x@…]

Bump on stephaner's comment. Why are models needed at all? Consider the case where you have an app for doing various things for your site. There may not be any models, but there may be an initial_data fixture to add in a default user or Site information.

[Alex Gaynor]

Requiring models for various things is a seperate issue, closing this as the bug here was fixed.