I'm making a very very reusable CMS in Django. I'm trying not to hardcode anything, so I want a config.py or something for the app itself.
I want to use it in templates (something like {{ config.SITE_NAME }}) and just regular Python code (views, models), etc.
How would I go about doing that?
Django already has the settings.py file and an interface to use the values from there, is that not good enough? Accessing settings in your code is easy:
from django.conf import settings
do_something_with(settings.MY_CONFIG_VARIABLE)
In your template it requires a bit more work, like making a context processor for example. This answer shows you have to make a context processor that exposes values from settings to your template.
settings.py serves this purpose already in django. You can add custom settings to it for your application.
https://docs.djangoproject.com/en/dev/topics/settings/#using-settings-in-python-code
When you create a django project, it automatically creates a settings.py file. Put your settings in that file, and then :-
from django.conf import settings
settings.YOUR_SETTING
also, if you have some settings, that will vary depending upon the machines (eg. production/test servers).
Then just add eg. conf/local_settings.py file and put the machine specific settings in that file, and in settings.py just do :-
from conf.local_settings import *
at the end of settings.py
Make sure you ignore local_settings.py from your VCS check-in (eg. in case of git add local_settings.py to .gitignore
Related
I have my project settings in settings.py file. There are database names, user names, host names etc. defined there. In project files I do import settings and then use the constants where needed like settings.HOST. For unit testing I would like to use different settings. How should I override the settings? I am not using django.
You could create a new file - say local_settings.py in which you override the specific settings for you debugging and testing purposes.
Then you add this block at the end of your settings.py
# Override these settings with local settings if such a file exists
try:
from local_settings import *
except ImportError as e:
pass
You should add local_settings.py to your .gitignore file to exclude this file from version control (if you are using git).
This is the standard way Django does this by the way.
I suppose the easiest way would be to move your settings.py to another folder for safekeeping and then make a new one, and edit that for debugging.
I have a python project that I'm using Django templates for to generate C++ source code.
I picked Django because the template language is quite restrictive and has a very large community making it easy for end-use developers to use and get help with.
I'm failing to add custom filters for my project (to translate one set of type names into another) because I have not done the normal django setup.
Instead:
from django.template import Context, Template
import django
if not django.conf.settings.configured : django.conf.settings.configure()
django.setup()
Lets me use Django templates perfectly but not define custom filters.
My custom filter is called ctypes_filters.py and I reference it in the template as
{% load ctypes_filters %}
Running my generation script results in the following error:
django.template.base.TemplateSyntaxError: 'ctypes_filters' is not a valid tag library: Template library ctypes_filters not found, tried
django.templatetags.ctypes_filters
How can I get django to find the filter without setting up a full Django project (database definitions etc)?
I know that other templating solutions are available (and are probably more light-weight) but I'm really keen to use Django's simple and elegant templates.
The location of Django template tags is done by convention rather than a configuration setting (see the code layout section of the template tags docs).
Put the ctypes_filter.py in a templatetags directory in an installed app (I've called it myapp here). Add an empty __init__.py to both the myapp and templatetags directories. The app doesn't need any other files you might commonly find in a Django app, like models.py or views.py.
myapp/
__init__.py
templatetags/
__init__.py
ctypes_filter.py
Then include myapp in your INSTALLED_APPS when configuring your settings.
django.conf.settings.configure(
INSTALLED_APPS=('myapp',),
)
Let's have a django project using a 3rd party application.
I'd like to override some of its modules without touching original files.
Simple subclassing is not possible here, need to override code transparently as many other apps rely on original class names and functions.
Project's structure looks like:
django_project/
__init__.py
settings.py
overrides/ <-- here is a subdir with apps overrides
__init__.py
payment/ <-- here is an example of app to override
__init__.py
admin.py
forms.py <-- this file is ignored, original is imported
models.py
tests.py
views.py
settings.py was modified with
INSTALLED_APPS=(
'satchmo_store.shop'
#'payment' # original values
'overrides.payment' # modified app
...
)
The above solution however does not work, because Django does not insert path of added app into modules search path (sys.path).
Django just loads admin.py, models.py, tests.py and views.py, other files like forms.py are ignored.
Is this behaviour documented somewhere ? What exactly placing a module name in INSTALLED_APPS does behind scenes ?
I hacked the situation with hardcoding new modules search path in manage.py and Apache's setting of WSGIPythonPath.
import os.path
import sys
DIRNAME = os.path.dirname(__file__)
APPS_OVERRIDE = os.path.join(DIRNAME, 'overrides')
if not APPS_OVERRIDE in sys.path:
sys.path.insert(1, APPS_OVERRIDE)
I doubt this is the right way. Cann't find a guide describing apps overriding.
So, how can I properly override external Django application in my project ?
The bonus question: Do I need to copy whole application directory tree, not just particular files which are really modified ? As far as I know, Python stops at first matching module path, so it won't import other modules available in following parts of the search path.
Example of how to override your form:
overrides/payment/forms.py
from django import forms
class YourNewFormThingy(forms.Form): pass
overrides/payment/models.py
from satchmo.payment import forms as satchmo_payment_forms
from . import forms
satchmo_payment_forms.SomeForm = forms.YourNewFormThingy
Try including payment as well along with override.payment as satchmo uses payment module to process payments and payment code is flexible enough to include your code as well.
I am relatively new to Django and one thing that has been on my mind is changing the database that will be used when running the project.
By default, the DATABASES 'default' is used to run my test project. But in the future, I want to be able to define a 'production' DATABASES configuration and have it use that instead.
In a production environment, I won't be able to "manage.py runserver" so I can't really set the settings.
I read a little bit about "routing" the database to use another database, but is there an easier way so that I won't need to create a new router every time I have another database I want to use (e.g. I can have test database, production database, and development database)?
You can just use a different settings.py in your production environment.
Or - which is a bit cleaner - you might want to create a file settings_local.py next to settings.py where you define a couple of settings that are specific for the current machine (like DEBUG, DATABASES, MEDIA_ROOT etc.) and do a from settings_local import * at the beginning of your generic settings.py file. Of course settings.py must not overwrite these imported settings.
Why you need a test database? Django create test database automatically before running unittest. And, database routing is not fit your purpose, it's for routing you read/write requests to different database. If you want to use a development database, set up a new DATABASE config in, say local_settings.py, and at the last of your settings.py, type
try:
from local_settings import *
except ImportError:
pass
There is nothing you can specify in the settings directly. The practice I use is to have addtional setting files for different environments which contain just the settings overwritten which I want to change, like database settings or cache settings for example. My project root application for example would contain the following files on a development environment (attention to the leading underscore):
...
settings.py
settings_dev.py
_settings_test.py
_settings_prod.py
...
Then in settings.py I would add the following lines of code to the beginning:
try:
from settings_prod import *
except ImportError:
try:
from settings_test import *
except ImportError:
from settings_dev import *
Since I am on dev environment it will only import my settings_dev file, since the others have a leading underscore.
When I deploy then to a production or testing environment I would rename the relevant files. For production: _settings_prod.py -> settings_prod.py, for testing: _settings_test.py -> settings_test.py. settings_dev.py can basically stay as is, since it will be only imported if the other two fail.
The last step you could simply do with automated deployment via fabric or other tools. An example with fabric would be something like run('mv _settings_prod.py settings_prod.py') for renaming.
I have a Django app with some management commands. In one of those commands, I need to write a log file which is located in /logs allong side views.py, models.py, etc ...
Considering that my management command script is in /management/commands/mycommand.py, is there any reliable way to determine the location of the appdir from within mycommand.py ?
PS: by reliable, I mean without using os.path.abspath( __file__ ), because the location of the file might change later on.
That's what your settings are for.
Add this to your settings
MY_APP_LOG_DIRECTORY = "path/to/logs"
In your view functions, use
from django.conf import settings
Now you can use settings.MY_APP_LOG_DIRECTORY all you want.