错误:序列项0:应为str实例，是否找到ForeignKey

Question

我正试图将我的模型添加到我的admin.py页面中，我不得不摆弄我的ManytoMany和Arrayfields字段以使其正常工作，但我还没有摆脱困境。

当我试图在我的管理页面中添加对象时，我收到了这个错误：Error: sequence item 0: expected str instance, ForeignKey found。

这是我的原始型号：

class Bucket(models.Model):
options = (
('personal', 'Personal'),
('social', 'Social'),
)

class BucketObjects(models.Manager):
def get_queryset(self):
return super().get_queryset().filter(Bucket.owner)
owner = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, related_name='buckets')
users = models.ManyToManyField(settings.AUTH_USER_MODEL)
category = models.CharField(max_length=30, choices=options)
name = models.CharField(max_length=35)
created = models.DateTimeField(default=timezone.now)
slug = models.SlugField(unique=True, blank=True, null=True) 
stock_count = models.IntegerField(blank=True, null=True)
stock_list = ArrayField(models.CharField(max_length=6,null=True),size=30,null=True)
about = models.CharField(max_length=75)
objects = models.Manager()
bucketobjects = BucketObjects()
class Meta:
ordering = ('-created',)
def total_stocks_calc(self):
self.stock_count = Bucket.objects.aggregate(Sum('stock_list', distinct=True))
self.save()
def get_absolute_url(self):
return reverse("bucket:bucket-view", kwargs={"slug": self.slug})
def __str__(self):
return self.stock_list

这是我的admin.py代码：

@admin.register(models.Bucket)
class AuthorAdmin(admin.ModelAdmin):
fields = models.Bucket._meta.get_fields()
list_display = ('id','owner','category', 'get_users', 'name', 'created',
'slug','stock_count','get_stocks', 'about')
prepopulated_fields = {'slug': ('name',), }

def get_users(self, obj):
return "n".join([u.users for u in obj.users.all()])

def get_stocks(self, obj):
return "n".join([s.stock_list for s in obj.stock_list.all()])

不确定我为什么会出现这个错误。

编辑：完整追溯错误：

Request Method: GET
Request URL: http://127.0.0.1:8000/bbucketmaster9/bucket/bucket/add/
Django Version: 3.1.4
Python Version: 3.8.5
Installed Applications:
['django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'rest_framework',
'django_filters',
'users',
'bucket',
'bucket_api']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware']

Traceback (most recent call last):
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/core/handlers/exception.py", line 47, in inner
response = get_response(request)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/core/handlers/base.py", line 179, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/contrib/admin/options.py", line 614, in wrapper
return self.admin_site.admin_view(view)(*args, **kwargs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/utils/decorators.py", line 130, in _wrapped_view
response = view_func(request, *args, **kwargs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/views/decorators/cache.py", line 44, in _wrapped_view_func
response = view_func(request, *args, **kwargs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/contrib/admin/sites.py", line 233, in inner
return view(request, *args, **kwargs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/contrib/admin/options.py", line 1653, in add_view
return self.changeform_view(request, None, form_url, extra_context)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/utils/decorators.py", line 43, in _wrapper
return bound_method(*args, **kwargs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/utils/decorators.py", line 130, in _wrapped_view
response = view_func(request, *args, **kwargs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/contrib/admin/options.py", line 1534, in changeform_view
return self._changeform_view(request, object_id, form_url, extra_context)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/contrib/admin/options.py", line 1568, in _changeform_view
ModelForm = self.get_form(
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/contrib/admin/options.py", line 709, in get_form
return modelform_factory(self.model, **defaults)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/forms/models.py", line 555, in modelform_factory
return type(form)(class_name, (form,), form_class_attrs)
File "/home/andres/stockbuckets.io/venv/lib/python3.8/site-packages/django/forms/models.py", line 266, in __new__
message = message % (', '.join(missing_fields),
Exception Type: TypeError at /bbucketmaster9/bucket/bucket/add/
Exception Value: sequence item 0: expected str instance, ForeignKey found

Answer 1

字段不能使用models.Bucket._meta.get_fields()get_fields(…)[Django-doc]将返回字段本身的元组，而不是这些字段的名称。

@admin.register(models.Bucket)
class AuthorAdmin(admin.ModelAdmin):
fields =models.Bucket._meta.get_fields()

您可以显式列出字段的名称，也可以使用

@admin.register(models.Bucket)
class AuthorAdmin(admin.ModelAdmin):
fields =[f.name for f inmodels.Bucket._meta.get_fields()]

但实际上您确实需要而不需要指定字段。正如fields上的文档所说：

如果fields和fieldsets选项都不存在，Django将默认显示不是AutoField并且具有editable=True，在单个字段集中，与字段的顺序相同在模型中定义。