引发 ImportError “无法导入设置” ENVIRONMENT_VARIABLE

Question

我正在尝试从 python 访问我的 MySQL 数据库。 它在 Openshift - Python 2.7、MySQL 5.5 上运行。 Django 和 Mysql 部署运行良好。 PHPMyAdmin 有效。

编辑 setup.py

setup(
    name='YourAppName',
    version='1.0',
    description='OpenShift App',
    author='Your Name',
    author_email='example@example.com',
    url='http://www.python.org/sigs/distutils-sig/',
    install_requires=['Django<=1.4', 'MySQL-python',],
)


DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': os.environ['OPENSHIFT_APP_NAME'],
        'USER': os.environ['OPENSHIFT_MYSQL_DB_USERNAME'],
        'PASSWORD': os.environ['OPENSHIFT_MYSQL_DB_PASSWORD'],
        'HOST': os.environ['OPENSHIFT_MYSQL_DB_HOST'],
        'PORT': os.environ['OPENSHIFT_MYSQL_DB_PORT']
    }
}

但是当我放这个

from django.db import connection

进入一些 py 脚本，我在日志中看到了这个：

mod_wsgi (pid=327977): Target WSGI script '/var/lib/openshift/542145275xxxxx9330000e6/app-root/runtime/repo/wsgi.py' cannot be loaded as Python module.
mod_wsgi (pid=327977): Exception occurred processing WSGI script '/var/lib/openshift/542145275xxxxx9330000e6/app-root/runtime/repo/wsgi.py'.
Traceback (most recent call last):
File "/var/lib/openshift/542145275xxxxx9330000e6/app-root/runtime/repo/wsgi.py", line 18, in <module>
from django.db import connection
File "/var/lib/openshift/542145275xxxxx9330000e6/python/virtenv/lib/python2.7/site-packages/Django-1.4-py2.7.egg/django/db/__init__.py", line 11, in <module>
if DEFAULT_DB_ALIAS not in settings.DATABASES:
File "/var/lib/openshift/542145275xxxxx9330000e6/python/virtenv/lib/python2.7/site-packages/Django-1.4-py2.7.egg/django/utils/functional.py", line 184, in inner
self._setup()
File "/var/lib/openshift/542145275xxxxx9330000e6/python/virtenv/lib/python2.7/site-packages/Django-1.4-py2.7.egg/django/conf/__init__.py", line 40, in _setup
raise ImportError("Settings cannot be imported, because environment variable %s is undefined." % ENVIRONMENT_VARIABLE)
ImportError: Settings cannot be imported, because environment variable DJANGO_SETTINGS_MODULE is undefined.

问题的原因可能是什么？ 感谢您的任何回答。

编辑： 在部署中，没有 settings.py（对此的引用应该在 DJANGO_SETTINGS_MODULE 中，对吗？所以现在我创建了一个。然后我像这样更改了变量：

export DJANGO_SETTINGS_MODULE=var.lib.openshift.542145275xxxxx9330000e6.app-root.runtime.repo.settings

我尝试了不同的值、子文件夹等。我不确定什么是正确的值。

我从 setup.py 中删除了 DATABASES 并将它们移动到我新创建的 settings.py 中。 它看起来像这样：

import os

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.mysql',
        'NAME': os.environ['OPENSHIFT_APP_NAME'],
        'USER': os.environ['OPENSHIFT_MYSQL_DB_USERNAME'],
        'PASSWORD': os.environ['OPENSHIFT_MYSQL_DB_PASSWORD'],
        'HOST': os.environ['OPENSHIFT_MYSQL_DB_HOST'],
        'PORT': os.environ['OPENSHIFT_MYSQL_DB_PORT']
    }
}

没有变化。 为什么 DJAGNO_SETTING_MODULE 仍然“未定义”（即使定义错误）？

Answer 1

这是一个 django 项目吗？如果是这样，您在 settings.py 文件中缺少很多设置，这里是 django 1.4 的默认 settings.py：

# Django settings for foo project.

DEBUG = True
TEMPLATE_DEBUG = DEBUG

ADMINS = (
    # ('Your Name', 'your_email@example.com'),
)

MANAGERS = ADMINS

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'.
        'NAME': '',                      # Or path to database file if using sqlite3.
        'USER': '',                      # Not used with sqlite3.
        'PASSWORD': '',                  # Not used with sqlite3.
        'HOST': '',                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': '',                      # Set to empty string for default. Not used with sqlite3.
    }
}

# Local time zone for this installation. Choices can be found here:
# http://en.wikipedia.org/wiki/List_of_tz_zones_by_name
# although not all choices may be available on all operating systems.
# On Unix systems, a value of None will cause Django to use the same
# timezone as the operating system.
# If running in a Windows environment this must be set to the same as your
# system time zone.
TIME_ZONE = 'America/Chicago'

# Language code for this installation. All choices can be found here:
# http://www.i18nguy.com/unicode/language-identifiers.html
LANGUAGE_CODE = 'en-us'

SITE_ID = 1

# If you set this to False, Django will make some optimizations so as not
# to load the internationalization machinery.
USE_I18N = True

# If you set this to False, Django will not format dates, numbers and
# calendars according to the current locale.
USE_L10N = True

# If you set this to False, Django will not use timezone-aware datetimes.
USE_TZ = True

# Absolute filesystem path to the directory that will hold user-uploaded files.
# Example: "/home/media/media.lawrence.com/media/"
MEDIA_ROOT = ''

# URL that handles the media served from MEDIA_ROOT. Make sure to use a
# trailing slash.
# Examples: "http://media.lawrence.com/media/", "http://example.com/media/"
MEDIA_URL = ''

# Absolute path to the directory static files should be collected to.
# Don't put anything in this directory yourself; store your static files
# in apps' "static/" subdirectories and in STATICFILES_DIRS.
# Example: "/home/media/media.lawrence.com/static/"
STATIC_ROOT = ''

# URL prefix for static files.
# Example: "http://media.lawrence.com/static/"
STATIC_URL = '/static/'

# Additional locations of static files
STATICFILES_DIRS = (
    # Put strings here, like "/home/html/static" or "C:/www/django/static".
    # Always use forward slashes, even on Windows.
    # Don't forget to use absolute paths, not relative paths.
)

# List of finder classes that know how to find static files in
# various locations.
STATICFILES_FINDERS = (
    'django.contrib.staticfiles.finders.FileSystemFinder',
    'django.contrib.staticfiles.finders.AppDirectoriesFinder',
#    'django.contrib.staticfiles.finders.DefaultStorageFinder',
)

# Make this unique, and don't share it with anybody.
SECRET_KEY = 'vwbv9j#2vauzpvya8#_qm=rgm&4w6t@yj+howvng0pv-6=@)ji'

# List of callables that know how to import templates from various sources.
TEMPLATE_LOADERS = (
    'django.template.loaders.filesystem.Loader',
    'django.template.loaders.app_directories.Loader',
#     'django.template.loaders.eggs.Loader',
)

MIDDLEWARE_CLASSES = (
    'django.middleware.common.CommonMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    # Uncomment the next line for simple clickjacking protection:
    # 'django.middleware.clickjacking.XFrameOptionsMiddleware',
)

ROOT_URLCONF = 'foo.urls'

# Python dotted path to the WSGI application used by Django's runserver.
WSGI_APPLICATION = 'foo.wsgi.application'

TEMPLATE_DIRS = (
    # Put strings here, like "/home/html/django_templates" or "C:/www/django/templates".
    # Always use forward slashes, even on Windows.
    # Don't forget to use absolute paths, not relative paths.
)

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.sites',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    # Uncomment the next line to enable the admin:
    # 'django.contrib.admin',
    # Uncomment the next line to enable admin documentation:
    # 'django.contrib.admindocs',
)

# A sample logging configuration. The only tangible logging
# performed by this configuration is to send an email to
# the site admins on every HTTP 500 error when DEBUG=False.
# See http://docs.djangoproject.com/en/dev/topics/logging for
# more details on how to customize your logging configuration.
LOGGING = {
    'version': 1,
    'disable_existing_loggers': False,
    'filters': {
        'require_debug_false': {
            '()': 'django.utils.log.RequireDebugFalse'
        }
    },
    'handlers': {
        'mail_admins': {
            'level': 'ERROR',
            'filters': ['require_debug_false'],
            'class': 'django.utils.log.AdminEmailHandler'
        }
    },
    'loggers': {
        'django.request': {
            'handlers': ['mail_admins'],
            'level': 'ERROR',
            'propagate': True,
        },
    }
}

您需要将此文件保存在一个目录中，然后将DJANGO_SETTINGS_MODULE 指向该文件的python 导入路径。这意味着它不是文件路径，而是类似于DJANGO_SETTINGS_MODULE=someapp.settings