Django学习（一）

安装python和django不提
首先来一个hello world

import sys
#settings
from django.conf import settings

settings.configure(
    DEBUG = True,
    SECRET_KEY = 'thisisthesecretkey',
    ROOT_URLCONF = __name__,
    MIDDLEWARE_CLASSES = (
        'django.middleware.common.CommonMiddleware',
        'django.middleware.csrf.CsrfViewMiddleware',
        'django.middleware.clickjacking.XFrameoptionsMiddleware',
        ),
    )
    
# view
from django.http import HttpResponse

def index(request):
    return HttpResponse('Hello World')


# urls
from django.conf.urls import url

urlpatterns = (
    url(r'^$',index),
    )


if __name__ == "__main__":
    from django.core.management import execute_from_command_line
    execute_from_command_line(sys.argv)

以上代码保存为hello.py
在cmd上敲命令

python hello.py runserver

注意路径问题

System check identified no issues (0 silenced).
August 28, 2018 - 19:13:06
Django version 2.1, using settings None
Starting development server at http://127.0.0.1:8000/
Quit the server with CTRL-BREAK.

默认本地地址127.0.0.1:8000
于是浏览器上可以显示第一个hello world了

本段代码是把一般网站的文件融合在了一起，比如视图、url、配置等，核心是''' return HttpResponse('Hello World')'''遇到请求返回helloworld

一些小修改：
添加wsgi应用
跨系统配置

import sys
import os
from django.conf import settings
from django.conf.urls import url
from django.core.wsgi import get_wsgi_application
from django.http import HttpResponse

DEBUG = os.environ.get('DEBUG','on') == 'on'
SECRET_KEY = os.environ.get('SECRET_KEY', os.urandom(32))
ALLOWED_HOSTS = os.environ.get('ALLOWED_HOSTS', 'localhost').split(',')
#settings

settings.configure(
    DEBUG = DEBUG,
    SECRET_KEY = 'thisisthesecretkey',
    ROOT_URLCONF = __name__,
    MIDDLEWARE_CLASSES = (
        'django.middleware.common.CommonMiddleware',
        'django.middleware.csrf.CsrfViewMiddleware',
        'django.middleware.clickjacking.XFrameoptionsMiddleware',
        ),
    )
    
# view


def index(request):
    return HttpResponse('Hello World')


# urls


application = get_wsgi_application()

urlpatterns = (
    url(r'^$',index),
    )


if __name__ == "__main__":
    from django.core.management import execute_from_command_line
    execute_from_command_line(sys.argv)

可以在系统直接配置DEBUG
如set DEBUG=off(windows)
export DEBUG=off(linux)