廖雪峰Python Day-2代码解析

源代码

import logging; logging.basicConfig(level=logging.INFO)

import asyncio, os, json, time
from datetime import datetime

from aiohttp import web

def index(request):
return web.Response(body=b'<h1>Awesome</h1>')

@asyncio.coroutine
def init(loop):
app = web.Application(loop=loop)
app.router.add_route('GET', '/', index)
srv = yield from loop.create_server(app.make_handler(), '127.0.0.1', 9000)
logging.info('server started at http://127.0.0.1:9000...') return srv

loop = asyncio.get_event_loop()
loop.run_until_complete(init(loop))
loop.run_forever()

代码解析

def index(request):

return web.Response(body=b'<h1>Awesome</h1>')

request为aiohttp.web.request实例, 包含http请求的信息, 一般不用自己构造

web.Response

构造并返回一个response实例, Response类声明为

class aiohttp.web.Response(*, status=200, headers=None, content_type=None, body=None, text=None)

@asyncio.coroutine

将generator标记为coroutine类型, coroutine内部可以用

yield from

调用另一个coroutine

app = web.Application(loop=loop)

创建web服务器实例

loop: event loop used for processing HTTP requests

web.Application用法

app.router.add_route('GET', '/', index)

为route路径注册处理函数

srv = yield from loop.create_server(app.make_handler(), '127.0.0.1', 9000)

loop.create_server创建一个TCP server

app.make_handler()

Creates HTTP protocol factory for handling requests.

yield from

返回一个创建好的,绑定IP和端口以及http协议簇的监听服务的协程

loop = asyncio.get_event_loop()

生成一个事件循环实例

loop.run_until_complete(init(loop))

运行init(loop), run_until_complete: If the argument is a coroutine object, it is wrapped by ensure_future().对loop进行了初始化, 创建了tcp server?

loop.run_forever()

一直运行

引用

廖雪峰Python教程Day2

Go-coding的博客

aiohttp官方文档

python官方文档