Django：TypeError：'ModelSignal' 对象不可调用

如何解决Django：TypeError：'ModelSignal' 对象不可调用

我有一段代码抛出错误： TypeError: 'ModelSignal' object is not callable。

当我要在我的项目中添加信号时，发生了这个错误。 为什么会出现这种类型的错误？你需要知道什么才能回答我的问题？

请帮助我。我是 Django 的新手。提前致谢。

这是我的 views.py 文件：

def registerPage(request):
    form = CreateUserForm()
    if request.method == "POST":
        form = CreateUserForm(request.POST)
        if form.is_valid():
            user =form.save()
            username = form.cleaned_data.get('username')
            messages.success(request,'Account successfully created for ' + username)

            return redirect ('login')

    context = {'form': form}
    return render(request,'accounts/register.html',context)

我的models.py文件：

from django.db import models
from django.contrib.auth.models import User

class Student(models.Model):
    user = models.OneToOneField(User,null=True,blank=True,on_delete=models.CASCADE)
    name = models.CharField(max_length=200)
    phone = models.CharField(max_length=200,null=True)
    email = models.CharField(max_length=200,null=True)
    profile_pic = models.ImageField(default= 'default-picture.jpg',null= True,blank= True)
    date_created = models.DateTimeField(auto_now_add=True,null=True)

    def __str__(self):
        return str(self.name)

我的signals.py文件：

from django.db.models.signals import post_save
from django.contrib.auth.models import Group,User
from .models import Student

def student_profile(sender,instance,created,**kwargs):
    if created:
        group = Group.objects.get(name = 'Student')
        instance.groups.add(group)
        Student.objects.create(
            user = instance,name = instance.username
        )
post_save(student_profile,sender= User)

我的 apps.py 文件：

from django.apps import AppConfig


class AccountsConfig(AppConfig):
    name = 'accounts'

    def ready(self):
        import accounts.signals

还有我的 settings.py 文件：

from pathlib import Path
import os

# Build paths inside the project like this: BASE_DIR / 'subdir'.
BASE_DIR = Path(__file__).resolve().parent.parent


# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/3.1/howto/deployment/checklist/

# SECURITY WARNING: keep the secret key used in production secret!
SECRET_KEY = '1dcgsc@63l$2w_%+90xqra@z=&(q!8sdxf*dg7k6=ptxi&k8o*'

# SECURITY WARNING: don't run with debug turned on in production!
DEBUG = True

ALLOWED_HOSTS = []


# Application definition

INSTALLED_APPS = [
    'django.contrib.admin','django.contrib.auth','django.contrib.contenttypes','django.contrib.sessions','django.contrib.messages','django.contrib.staticfiles','accounts.apps.AccountsConfig','django_filters',]

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',]

ROOT_URLCONF = 'cmp.urls'

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates','DIRS': [],'APP_DIRS': True,'OPTIONS': {
            'context_processors': [
                'django.template.context_processors.debug','django.template.context_processors.request','django.contrib.auth.context_processors.auth','django.contrib.messages.context_processors.messages',],},]

WSGI_APPLICATION = 'cmp.wsgi.application'


# Database
# https://docs.djangoproject.com/en/3.1/ref/settings/#databases

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3','NAME': BASE_DIR / 'db.sqlite3',}
}


# Password validation
# https://docs.djangoproject.com/en/3.1/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',{
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',{
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',{
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',]


# Internationalization
# https://docs.djangoproject.com/en/3.1/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'Asia/Dhaka'

USE_I18N = True

USE_L10N = True

USE_TZ = True


# Static files (CSS,JavaScript,Images)
# https://docs.djangoproject.com/en/3.1/howto/static-files/

STATIC_URL = '/static/'
MEDIA_URL = '/images/'

STATICFILES_DIRS = [
    os.path.join(BASE_DIR,'static')
]

MEDIA_ROOT = os.path.join(BASE_DIR,'static/images')

解决方法

您正在调用不可调用的 post_save 对象。试试post_save.connect()。

from django.db.models.signals import post_save
from django.contrib.auth.models import Group,User
from .models import Student

def student_profile(sender,instance,created,**kwargs):
    if created:
        group = Group.objects.get(name = 'Student')
        instance.groups.add(group)
        Student.objects.create(
            user = instance,name = instance.username
        )
post_save.connect(student_profile,sender= User)

或者您也可以尝试使用 receiver 装饰器：

from django.db.models.signals import post_save
from django.contrib.auth.models import Group,User
from django.dispatch import receiver
from .models import Student

@receiver(post_save,sender=User)
def student_profile(sender,name = instance.username
        ).save()