python学习6 web开发

wsgi自带,用语构建简单服务器

• 例子

from wsgiref.simple_server import make_server

def index(env, res):
    res('200 ok', [('Content-Type', 'text/html')])
    print(env['PATH_INFO'][1:])  # method = env['REQUEST_METHOD']
    body =  '<h1>hello %s </h1>' % (env['PATH_INFO'][1:] or 'index')
    return [body.encode('utf8')]

# 建立服务器
server = make_server('127.0.0.1', 3000, index)
print('Server start at 3000...')

# 监听请求
server.serve_forever()

aiohttp基于asyncio实现的HTTP框架

import asyncio
from aiohttp import web

@asyncio.coroutine
def index(request):
    yield from asyncio.sleep(0.5)
    text = '<h1>hello, %s!</h1>' % (request.match_info['name'] or 'index')
    return web.Response(body=text.encode('utf8'))

@asyncio.coroutine
def init(loop):
    app = web.Application(loop=loop)
    app.router.add_route('GET', '/{name}', index)
    # 建立服务器
    srv = yield from loop.create_server(app.make_handler(), '127.0.0.1', 3000)
    print('Server started at http://127.0.0.1:3000...')
    return srv

# 获取EventLoop:
loop = asyncio.get_event_loop()
# 执行coroutine
loop.run_until_complete(init(loop))
# 监听请求
loop.run_forever()

jinja2

• 简单的模版初始化和使用

from jinja2 import Environment, FileSystemLoader

def init_jinja2():
    path = os.path.abspath('.')
    env = Environment(loader=FileSystemLoader(path))
    return env

__template__ = init_jinja2()
....
body = __template__.get_template('example.html').render(**kw).encode('utf-8')
....

aiomysql 为asyncio提供异步mmysql IO的驱动

import asyncio
import aiomysql

loop = None

@asyncio.coroutine
def connect():
    global loop
    # 创建链接
    conn = yield from aiomysql.connect(
        host= '127.0.0.1',
        port= 3306,
        user= 'root',
        password= 'password',
        db= 'awesome',
        loop= loop)
    # 打开游标
    cur = yield from conn.cursor()
    # 执行SQL语句
    yield from cur.execute('SELECT * FROM users')
    print(cur.description)
    # 获取结果集
    r = yield from cur.fetchall()
    print(r)
    yield from cur.close()
    conn.close()

loop = asyncio.get_event_loop()
loop.run_until_complete(connect())