Django-원형 모델 가져 오기 문제

Django-원형 모델 가져 오기 문제

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나는 이것을 정말로 얻지 못하고있다. 그래서 누군가 이것이 이것이 어떻게 작동하는지 설명 할 수 있다면 나는 그것을 매우 감사 할 것이다. 두 개의 응용 프로그램, 계정 및 테마가 있습니다. 여기에 내 설정 목록이 있습니다.

INSTALLED_APPS = (
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'accounts',
    'themes',
)

계정에서 이렇게하려고합니다.

from themes.models import Theme

class Account(models.Model):
    ACTIVE_STATUS = 1
    DEACTIVE_STATUS = 2
    ARCHIVE_STATUS = 3
    STATUS_CHOICES = (
        (ACTIVE_STATUS, ('Active')),
        (DEACTIVE_STATUS, ('Deactive')),
        (ARCHIVE_STATUS, ('Archived')),
    )

    id = models.AutoField(primary_key=True)
    name = models.CharField(max_length=250)
    slug = models.SlugField(unique=True, verbose_name='URL Slug')
    status = models.IntegerField(choices=STATUS_CHOICES, default=ACTIVE_STATUS, max_length=1)
    owner = models.ForeignKey(User)
    enable_comments = models.BooleanField(default=True)
    theme = models.ForeignKey(Theme)
    date_created = models.DateTimeField(default=datetime.now)

그리고 내 테마 모델에서 :

class Theme(models.Model):
    id = models.AutoField(primary_key=True)
    name = models.CharField(max_length=250)
    slug = models.SlugField(unique=True, verbose_name='URL Slug')
    date_created = models.DateTimeField(default=datetime.now)

class Stylesheet(models.Model):
    id = models.AutoField(primary_key=True)
    account = models.ForeignKey(Account)
    date_created = models.DateTimeField(default=datetime.now)
    content = models.TextField()

Django에서 다음 오류가 발생합니다.

from themes.models import Theme
ImportError: cannot import name Theme

이것은 일종의 순환 수입 문제입니까? 게으른 참조를 사용해 보았지만 작동하지 않는 것 같습니다!

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가져 오기를 제거하고 Theme대신 모델 이름을 문자열로 사용하십시오.

theme = models.ForeignKey('themes.Theme')

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Something I haven't seen mentioned anywhere in sufficient detail is how to properly formulate the string inside ForeignKey when referencing a model in a different app. This string needs to be app_label.model_name. And, very importantly, the app_label is not the entire line in INSTALLED_APPS, but only the last component of it. So if your INSTALLED_APPS looks like this:

INSTALLED_APPS = (
...
    'path.to.app1',
    'another.path.to.app2'
)

then to include a ForeignKey to a model in app2 in an app1 model, you must do:

app2_themodel = ForeignKey('app2.TheModel')

I spent quite a long time trying to solve a circular import issue (so I couldn't just from another.path.to.app2.models import TheModel) before I stumbled onto this, google/SO was no help (all the examples had single component app paths), so hopefully this will help other django newbies.

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Upto Django 1.7:

Use get_model function from django.db.models which is designed for lazy model imports.:

from django.db.models import get_model
MyModel = get_model('app_name', 'ModelName')

In your case:

from django.db.models import get_model
Theme = get_model('themes', 'Theme')

Now you can use Theme

For Django 1.7+:

from django.apps import apps
apps.get_model('app_label.model_name')

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Since Django 1.7 correct way is to go like this:

from django.apps import apps

YourModel = apps.get_model('your_app_name', 'YourModel')

See: https://docs.djangoproject.com/ja/1.9/ref/applications/#django.apps.apps.get_model

참고URL : https://stackoverflow.com/questions/4379042/django-circular-model-import-issue