python - Django : python manage. py runserver(多个错误)

Question

根据 youtube 上的教程，我最近开始将 Django 用于我的第一个 Web 应用程序，在此命令之前一切都很好:$ python manage.py runserver这意味着我能够创建一个虚拟环境并使用以下命令创建一个项目:$ python3 -m django startproject <projectname> .
这是我的管理.py 好像:

"""Django's command-line utility for administrative tasks."""
import os
import sys


def main():
    """Run administrative tasks."""
    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'django_blog.settings')
    try:
        from django.core.management import execute_from_command_line
    except ImportError as exc:
        raise ImportError(
            "Couldn't import Django. Are you sure it's installed and "
            "available on your PYTHONPATH environment variable? Did you "
            "forget to activate a virtual environment?"
        )
    execute_from_command_line(sys.argv)


if __name__ == '__main__':
    main()

以下是我的一些不同尝试和错误:$ python manage.py runserver错误:

  File "manage.py", line 22, in <module>
    main()
  File "manage.py", line 14, in main
    "Couldn't import Django. Are you sure it's installed and "
ImportError: Couldn't import Django. Are you sure it's installed and available on your PYTHONPATH environment variable? Did you forget to activate a virtual environment?

尝试 n°1:$ python pip install django错误:python: can't open file 'pip': [Errno 2] No such file or directory$ python -m pip install gekko在 $ python pip install django 之后仍然给出与上述相同的错误
尝试 n°2:$ python3 manage.py runserver和 $ python3.6 manage.py runserver两者都给出相同的错误:

File "/usr/local/lib/python3.6/sqlite3/dbapi2.py", line 27, in <module>
from _sqlite3 import *
ModuleNotFoundError: No module named '_sqlite3'

尝试使用:$ pip3 install pysqlite3 $ sudo apt-get install libsqlite3-dev然后在里面~/Downloads/Python-3.6.2$ ./configure --enable-loadable-sqlite-extension && make && sudo make install问题仍然存在。
尝试 n°3:$ python3.5 manage.py runserver

Traceback (most recent call last):
  File "manage.py", line 11, in main
    from django.core.management import execute_from_command_line
ImportError: No module named 'django'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "manage.py", line 22, in <module>
    main()
  File "manage.py", line 14, in main
    "Couldn't import Django. Are you sure it's installed and "
ImportError: Couldn't import Django. Are you sure it's installed and available on your PYTHONPATH environment variable? Did you forget to activate a virtual environment?

这是最近的错误:

from django.urls import path
ImportError: cannot import name path

这是我的 urls.py

from django.urls import path

urlpatterns = [
    path('admin/', admin.site.urls),
]

这是我运行 sudo tree 时得到的结果linux上的命令

thalagalage@3n1gm4:~/chamika/Python/DjangoBlog$ sudo tree
.
├── django_blog
│   ├── django_blog
│   │   ├── asgi.py
│   │   ├── __init__.py
│   │   ├── __init__.pyc
│   │   ├── __pycache__
│   │   │   ├── __init__.cpython-36.pyc
│   │   │   ├── settings.cpython-36.pyc
│   │   │   └── urls.cpython-36.pyc
│   │   ├── settings.py
│   │   ├── settings.pyc
│   │   ├── urls.py
│   │   ├── urls.pyc
│   │   └── wsgi.py
│   ├── manage.py
│   └── manage.sublime-workspace
└── django_env
    ├── bin
    │   ├── activate
    │   ├── activate.csh
    │   ├── activate.fish
    │   ├── activate.ps1
    │   ├── activate_this.py
    │   ├── activate.xsh
    │   ├── django-admin
    │   ├── django-admin.py
    │   ├── easy_install
    │   ├── easy_install3
    │   ├── easy_install-3.6
    │   ├── easy_install3.6
    │   ├── pip
    │   ├── pip3
    │   ├── pip-3.6
    │   ├── pip3.6
    │   ├── __pycache__
    │   │   └── django-admin.cpython-36.pyc
    │   ├── python -> /usr/bin/python3
    │   ├── python3 -> python
    │   ├── python3.6 -> python
    │   ├── sqlformat
    │   ├── wheel
    │   ├── wheel3
    │   ├── wheel-3.6
    │   └── wheel3.6

以下是我为了进入我的虚拟环境而使用的分步命令，直到我遇到 manage.py runserver抛出 ModuleNotFoundError: No module named '_sqlite3' 的命令.

thalagalage@3n1gm4:~/chamika/Python/DjangoBlog$ ll
total 16
drwxr-xr-x  4 thalagalage thalagalage 4096 sept.  5 19:02 ./
drwxrwxr-x 11 thalagalage thalagalage 4096 sept.  5 18:13 ../
drwxr-xr-x  3 thalagalage thalagalage 4096 sept.  5 19:32 django_blog/
drwxr-xr-x  4 thalagalage thalagalage 4096 sept.  5 18:03 django_env/
thalagalage@3n1gm4:~/chamika/Python/DjangoBlog$ source django_env/bin/activate
(django_env) thalagalage@3n1gm4:~/chamika/Python/DjangoBlog$ python3 -m django --version
3.1.1
(django_env) thalagalage@3n1gm4:~/chamika/Python/DjangoBlog$ cd django_blog
(django_env) thalagalage@3n1gm4:~/chamika/Python/DjangoBlog/django_blog$ ll
total 32
drwxr-xr-x 3 thalagalage thalagalage  4096 sept.  5 19:32 ./
drwxr-xr-x 4 thalagalage thalagalage  4096 sept.  5 19:02 ../
drwxr-xr-x 3 thalagalage thalagalage  4096 sept.  6 01:02 django_blog/
(django_env) thalagalage@3n1gm4:~/chamika/Python/DjangoBlog/django_blog$ python3 manage.py runserver

谢谢您的帮助!

Answer 1

您应该做的第一件事是创建一个虚拟环境。虚拟环境是放置你的包的地方，例如 Django 是模块之一。为了创建虚拟环境，您有多种选择，例如 pipenv , virtualenv ， ETC。
A) 虚拟环境

您可以安装virtualenv使用以下命令:

pip3 install virtualenv

创建一个新的虚拟环境。常见的 virtualenv 名称是 venv , env等

virtualenv --python=python3 --no-site-package <virtualenv-name>
#example:
virtualenv --python=python3 --no-site-package venv

激活虚拟环境。在当前目录中打开终端(在 linux 和 Mac OSX 中)或 powershell(在 windows 中)并执行以下命令:

source <virtualenv-name>/bin/activate

安装所需的软件包。您的 virtualenv 的名称应该放在括号中的 shell 前面。

(<virtualenv-name>) pip3 install django

最后成功运行服务器。

(<virtualenv-name>) python3 manage.py runserver

B) Pipenv

安装管道。

pip3 install pipenv

或者在linux中你可以执行以下几行:

sudo apt install software-properties-common python-software-properties
sudo add-apt-repository ppa:pypa/ppa
sudo apt update
sudo apt install pipenv

使用 pipenv 创建新环境您必须在终端中输入以下行。

pipenv --python 3.6

安装您需要的软件包。

pipenv install django

运行服务器。

python3 manage.py runserver

PS:如果运行项目仍然有问题，最好从头开始创建一个新项目:

如上所述创建一个新的 virtualenv。

激活虚拟环境。

安装 Django。

(venv) pip3 install django

创建新的 Django 项目。

(venv) django-admin startproject <project-name>

将目录更改为 django 项目目录，然后运行服务器。

(venv) cd <project-name>
(venv) python3 manage.py makemigrations
(venv) python3 manage.py migrate
(venv) python3 manage.py runserver