How to reload modules in django shell?

Question

I am working with Django and use Django shell all the time. The annoying part is that while the Django server reloads on code changes, the shell does not, so every time I make a change to a method I am testing, I need to quit the shell and restart it, re-import all the modules I need, reinitialize all the variables I need etc. While iPython history saves a lot of typing on this, this is still a pain. Is there a way to make django shell auto-reload, the same way django development server does?

I know about reload(), but I import a lot of models and generally use from app.models import * syntax, so reload() is not much help.

Answer 1

I'd suggest use IPython autoreload extension.

./manage.py shell

In [1]: %load_ext autoreload
In [2]: %autoreload 2

And from now all imported modules would be refreshed before evaluate.

In [3]: from x import print_something
In [4]: print_something()
Out[4]: 'Something'

 # Do changes in print_something method in x.py file.

In [5]: print_something()
Out[5]: 'Something else'

Works also if something was imported before %load_ext autoreload command.

./manage.py shell
In [1]: from x import print_something
In [2]: print_something()
Out[2]: 'Something'

 # Do changes in print_something method in x.py file.

In [3]: %load_ext autoreload
In [4]: %autoreload 2
In [5]: print_something()
Out[5]: 'Something else'

There is possible also prevent some imports from refreshing with %aimport command and 3 autoreload strategies:

%autoreload

• Reload all modules (except those excluded by %aimport) automatically now.

%autoreload 0

• Disable automatic reloading.

%autoreload 1

• Reload all modules imported with %aimport every time before executing the Python code typed.

%autoreload 2

• Reload all modules (except those excluded by %aimport) every time before executing the Python code typed.

%aimport

• List modules which are to be automatically imported or not to be imported.

%aimport foo

• Import module ‘foo’ and mark it to be autoreloaded for %autoreload 1

%aimport -foo

• Mark module ‘foo’ to not be autoreloaded.

This generally works good for my use, but there are some cavetas:

• Replacing code objects does not always succeed: changing a @property in a class to an ordinary method or a method to a member variable can cause problems (but in old objects only).
• Functions that are removed (eg. via monkey-patching) from a module before it is reloaded are not upgraded.
• C extension modules cannot be reloaded, and so cannot be autoreloaded.

Answer 2

My solution to it is I write the code and save to a file and then use:

python manage.py shell < test.py

So I can make the change, save and run that command again till I fix whatever I'm trying to fix.

Answer 3

I recommend using the django-extensions project like stated above by dongweiming. But instead of just 'shell_plus' management command, use:

manage.py shell_plus --notebook

This will open a IPython notebook on your web browser. Write your code there in a cell, your imports etc. and run it.

When you change your modules, just click the notebook menu item 'Kernel->Restart'

There you go, your code is now using your modified modules.