WEB框架

1. 负责与浏览器收发消息(socket通信)
2. 根据用户访问不同的路径和信息执行不同的函数
3. 从HTML文件中读取内容(或者生成HTML数据),并且完成字符串的替换

• 框架自带1,2,3全部功能                 --> Tornado
• 框架自带2和3,使用别人的1          --> Django
• 框架自带2,使用第三方的1和3      --> Flask

Django初探

用WSGIREF模块简单写一个服务器

from wsgiref.simple_server import make_server


def run_server(environ, start_response):
    start_response('200 OK', [('Content-Type', 'text/html;charset=utf8'), ])  # 设置HTTP响应的状态码和头信息
    url = environ['PATH_INFO']  # 取到用户输入的url

    return [b'this is WSGI server', ]


if __name__ == '__main__':
    httpd = make_server('127.0.0.1', 8090, run_server)
    httpd.serve_forever()

安装Django和运行Django服务

django-admin startproject mysite

mysite/
├── manage.py  # 管理文件
└── mysite  # 项目目录
    ├── __init__.py
    ├── settings.py  # 配置
    ├── urls.py  # 路由 --> URL和函数的对应关系
    └── wsgi.py  # runserver命令就使用wsgiref模块做简单的web server

python manage.py runserver 127.0.0.1:8000

Pycharm中建立Django项目和启动Django服务

D:\Software\PyCharm\bin\runnerw.exe C:\Users\Minko\AppData\Local\Programs\Python\Python36\python.exe D:/Mysite/manage.py runserver 8000
Performing system checks...

System check identified no issues (0 silenced).

You have 13 unapplied migration(s). Your project may not work properly until you apply the migrations for app(s): admin, auth, contenttypes, sessions.
Run 'python manage.py migrate' to apply them.
July 10, 2018 - 10:47:08
Django version 1.11.14, using settings 'Mysite.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CTRL-BREAK.

It worked!
Congratulations on your first Django-powered page.
Next, start your first app by running python manage.py startapp [app_label].
You're seeing this message because you have DEBUG = True in your Django settings file and you haven't configured any URLs. Get to work!

返回一个HTML页面

urlpatterns = [
    url(r'^admin/', admin.site.urls),
]

from django.shortcuts import HttpResponse

def myfunc(request):
    '''request参数保存了所有和用户浏览器请求相关的数据'''
    return HttpResponse(
        '<h1 style="color: maroon; text-align: center;">First Message</h1>') 
urlpatterns = [ url(r'^admin/', admin.site.urls), url(r'^minko/', myfunc), ]

def index_html(request):
    with open("./templates/test.html", "r", encoding="utf-8") as f:
        data = f.read()
    return HttpResponse(data)

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^minko/', myfunc),
    url(r'^index/', index_html),
]

1. 检查了test.html文件,发现其中的样式是绝对路径,并没有通过cdn加速来引用,那么引用的文件需要放在哪里呢?
2. Django肯定考虑到了文件的传输,有没有更简便的方法传输文件呢?

TEMPLATES = [
    {
        'BACKEND': 'django.template.backends.django.DjangoTemplates',
        'DIRS': [os.path.join(BASE_DIR, 'templates')]
        ,
        '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',
            ],
        },
    },
]

BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

from django.shortcuts import render

def index_html(request):
    return render(request, "test.html")

# 存放静态文件的目录的别名
STATIC_URL = "/static/"

# 所有静态文件都放在下边配置的文件夹里
STATICFILES_DIRS = [
    os.path.join(BASE_DIR, 'static')
]

<link rel="stylesheet" href="/static/bootstrap/css/bootstrap.min.css">
<script src="/static/jquery-3.3.1.min.js"></script>
<script src="/static/bootstrap/js/bootstrap.min.js"></script>