Get absolute path of django app

问题:

I am writing a unit test that needs to access an image file that I put in "fixtures" directory right under my django app directory. I want to open up this image file in my test using relative path, which would require me to get the absolute path of the django app. Is there a way to get the absolute path of the django app?

回答1:

Python modules (including Django apps) have a __file__ attribute that tells you the location of their __init__.py file on the filesystem, so

import appname
pth = os.path.dirname(appname.__file__)

should do what you want.

In usual circumstances, os.path.absname(appname.__path__[0]), but it's possible for apps to change that if they want to import files in a weird way.

(I do always do PROJECT_ROOT = os.path.dirname(os.path.abspath(__file__)) in my settings.py, though -- makes it easy for the various settings that need to be absolute paths.)

回答2:

Normally, this is what I add in my settings.py file so I can reference the project root.

import os.path

PROJECT_ROOT = os.path.abspath(os.path.dirname(__file__))

This method will get the directory of any python file.

回答3:

So the accepted answer usually works fine. However, for

• namespace packages with multiple paths, or
• apps which explicitly configure their paths in the config,

their intended path may not agree with the __file__ attribute of the module.

Django (1.7+) provides the AppConfig.path attribute - which I think is clearer even in simple cases, and which covers these edge cases too.

The application docs tell you how to get the AppConfig object. So to get AppConfig and print the path from it:

from django.apps import apps
print(apps.get_app_config('app_label').path)

Edit: Altered example for how to use get_app_config to remove dots, which seems to have been confusing. Here are the docs for reference.

回答4:

În newer versions of Django (I don't know when it started, I assume it's there for many years now), the default settingy.py contains an entry

# Build paths inside the project like this: os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

which you can use by importing the settings file like this

import os    
from my_project_name.settings import BASE_DIR

os.path.join(BASE_DIR, ...)

回答5:

Keep in mind that appname.__path__ is a list:

import appname
APP_ROOT = os.path.abspath(appname.__path__[0])
file_path = os.path.join(APP_ROOT, "some_file.txt")

回答6:

Python3.4 and above comes with standard library pathlib.

from pathlib import Path
import appmodule

pth = Path(appmodule.__file__).parent / 'fixtures'
if pth.exists():
     "Your code here"

parent will give you the path of your app directory, and / will append fixtures as path.