使用 manage.py 运行服务器时收到错误答案

【问题标题】：Recieving errors when running server with manage.py使用 manage.py 运行服务器时收到错误
【发布时间】：2021-02-22 03:59:06
【问题描述】：

我试图在我的笔记本电脑上运行服务器，当我在控制台中输入“python manage.py runserver”时我收到一些错误。可能是我需要导入一些我尝试过“pip install python-cron”的模块，但这没有用。错误说：

[2020-11-10 09:04:47,241] autoreload: INFO - Watching for file changes with StatReloader
Exception in thread django-main-thread:
Traceback (most recent call last):
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/threading.py", line 932, in _bootstrap_inner
    self.run()
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/utils/autoreload.py", line 53, in wrapper
    fn(*args, **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/core/management/commands/runserver.py", line 109, in inner_run
    autoreload.raise_last_exception()
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/utils/autoreload.py", line 76, in raise_last_exception
    raise _exception[1]
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/core/management/__init__.py", line 357, in execute
    autoreload.check_errors(django.setup)()
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/utils/autoreload.py", line 53, in wrapper
    fn(*args, **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/__init__.py", line 24, in setup
    apps.populate(settings.INSTALLED_APPS)
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/apps/registry.py", line 91, in populate
    app_config = AppConfig.create(entry)
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/site-packages/django/apps/config.py", line 90, in create
    module = import_module(entry)
  File "/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1014, in _gcd_import
  File "<frozen importlib._bootstrap>", line 991, in _find_and_load
  File "<frozen importlib._bootstrap>", line 973, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'django_cron'

我拥有的 cron.py 文件是：

from django.contrib.auth.models import User

import os
import datetime
from crontab import CronTab
#from django_common.helper import send_mail
from django_cron import CronJobBase, Schedule
from .models import Photo
from PIL import Image


class PhotoDeleteCronJob(CronJobBase):

    RUN_EVERY_MINS = 1



    schedule = Schedule(run_every_mins=RUN_EVERY_MINS)
    code = 'cron.PhotoDeleteCronJob'

    def do(self):
        delet = Photo.objects.all()
        delet.delete()

如果您需要查看任何其他文件，请提前致谢。

【问题讨论】：

你试过 pip install pip install django-cron 吗？
你能从 settings.py 分享你安装的应用吗？

标签： python django cron cron-task

【解决方案1】：

尝试用这个安装 django cron

pip install django-cron

我认为您已启用虚拟环境，然后尝试启动服务器很多人都会犯这个错误！！

您必须重新安装 django 所需的所有外部库（不是 os math numpy 等基础库）

也通过此代码进行迁移

python manage.py makemigrations django-cron

这些都是愚蠢的错误

【讨论】：

【解决方案2】：

如果你错过了，请执行以下步骤，

第 1 步： pip install django-cron

第 2 步：打开你的 settings.py 并在你的 installed_app 中注册它 djnago-cron

第 3 步：在 settings.py 中安装应用程序后，您需要进行迁移 python manage.py makemigrations djnago-cron

第 4 步：比迁移这些更改 python manage.py migrate

第 5 步：您现在可以开始运行服务器了 `python manage.py runserver

【讨论】：