Python网络编程之 select(2)实现一个最简单的webserver

          上次介绍了Python 的select模块实现非阻塞socket编程。于是就用select写了一个最简单的web Server,能够实现最基本的HTML文件访问和Python脚本的访问,当然有很多bug，只是想通过这个这个对socket编程以及HTTP协议有一些了解。

　　　　

__author__ = 'gongxingfa'

import socket
import os
import traceback
import select
from os.path import splitext

HOST = 'localhost'
PORT = 8000
BUFSIZ = 1024
ADDR = (HOST, PORT)

# context
socketMap = {}
requestMap = {}
r, w, e = [], [], []

# setting server socket
serverSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
serverSocket.bind(ADDR)
serverSocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
serverSocket.listen(100)


class Request(object):
    def __init__(self, message):
        headers = {}
        try:
            message = message.strip().splitlines()
            self.start = message[0].strip().split(' ')
            for i in range(1, len(message)):
                line = message[i]
                if line.strip() != '':
                    index = line.index(':')
                    key = line[0: index]
                    value = line[index + 1:]
                    headers[key] = value
        except IndexError, e:
            pass
        self.headers = headers

    def method(self):
        return self.start[0]

    def url(self):
        return self.start[1]

    def version(self):
        return self.start[2]


def handler(req, reqClnt):
    try:
        path = '.' + req.url()
        ext = splitext(path)
        if ext[1] == '':
            f = os.popen('python ' + path + '.py')
            reqClnt.send('\n'.join(f.readlines()))
            f.close()
        else:
            f = open('.' + req.url())
            reqClnt.send('\n'.join(f.readlines()))
            f.close()
    except IOError, e:
        reqClnt.send(str(e))


socketFileno = serverSocket.fileno()
socketMap[socketFileno] = serverSocket
print 'start socket ', socketFileno, '*' * 50

try:
    while True:
        r, w, e = [], [], []
        for fd in socketMap:
            r.append(fd)
            w.append(fd)
            e.append(fd)
        r, w, e = select.select(r, w, e, 1)
        for fd in r:
            isocket = socketMap[fd]
            if fd == socketFileno:
                print 'accepting...........'
                clientSock, clientAddr = isocket.accept()
                print 'connection from ', clientAddr
                clientFileno = clientSock.fileno()
                r.append(clientFileno)
                w.append(clientFileno)
                e.append(clientFileno)
                socketMap[clientFileno] = clientSock
            else:
                print 'reading............'
                requestMap[fd] = Request(isocket.recv(BUFSIZ))

        for fd in w:
            try:
                req = requestMap[fd]
            except KeyError, e:
                pass
            else:
                print 'writing.............'
                osocket = socketMap[fd]
                handler(req, osocket)
                del requestMap[fd]

        for fd in e:
            esocket = socketMap[fd]
            print 'socket close ', fd
            esocket.close()
            del socketMap[fd]
        print 'no data coming'

except Exception, e:
    print traceback.print_exc()
    serverSocket.close()