澳门新浦京娱乐游戏Python进阶【第一篇】socket,python进阶socket

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Python进阶【第一篇】socket,python进阶socket

本章内容

  1、socket

  2、IO多路复用

  3、socketserver

想要构建聊天应用,或者甚至是游戏吗?那么,socket服务器将成为你迈出的第一步。一旦你了解了创建服务器的基本功能,那么后续的优化步骤就会变得同样简单。

1.socket模块

要使用socket.socket()函数来创建套接字。其语法如下:

socket.socket(socket_family,socket_type,protocol=0)

 

socket_family可以是如下参数:

  socket.AF_INET IPv4(默认)
  socket.AF_INET6 IPv6

  socket.AF_UNIX 只能够用于单一的Unix系统进程间通信

socket_type可以是如下参数:

  socket.SOCK_STREAM  流式socket , for TCP (默认)
  socket.SOCK_DGRAM   数据报式socket , for UDP

  socket.SOCK_RAW
原始套接字,普通的套接字无法处理ICMP、IGMP等网络报文,而SOCK_RAW可以;其次,SOCK_RAW也可以处理特殊的IPv4报文;此外,利用原始套接字,可以通过IP_HDRINCL套接字选项由用户构造IP头。
  socket.SOCK_RDM
是一种可靠的UDP形式,即保证交付数据报但不保证顺序。SOCK_RAM用来提供对原始协议的低级访问,在需要执行某些特殊操作时使用,如发送ICMP报文。SOCK_RAM通常仅限于高级用户或管理员运行的程序使用。
  socket.SOCK_SEQPACKET 可靠的连续数据包服务

protocol参数:

  0  (默认)与特定的地址家族相关的协议,如果是 0
,则系统就会根据地址格式和套接类别,自动选择一个合适的协议

Socket

socket起源于Unix,而Unix/Linux基本哲学之一就是“一切皆文件”,对于文件用【打开】【读写】【关闭】模式来操作。socket就是该模式的一个实现,socket即是一种特殊的文件,一些socket函数就是对其进行的操作(读/写IO、打开、关闭)

基本上,Socket
是任何一种计算机网络通讯中最基础的内容。例如当你在浏览器地址栏中输入
 时,你会打开一个套接字,然后连接到
 并读取响应的页面然后然后显示出来。而其他一些聊天客户端如
gtalk 和 skype 也是类似。任何网络通讯都是通过 Socket 来完成的。

Python 官方关于 Socket
的函数请看 

socket和file的区别:

  1、file模块是针对某个指定文件进行【打开】【读写】【关闭】

  2、socket模块是针对
服务器端 和 客户端Socket 进行【打开】【读写】【关闭】

澳门新浦京娱乐游戏 1

那我们就先来创建一个socket服务端吧

澳门新浦京娱乐游戏 2澳门新浦京娱乐游戏 3

import socket

sk = socket.socket()
sk.bind(("127.0.0.1",8080))
sk.listen(5)

conn,address = sk.accept()
sk.sendall(bytes("Hello world",encoding="utf-8"))

server

澳门新浦京娱乐游戏 4澳门新浦京娱乐游戏 5

import socket

obj = socket.socket()
obj.connect(("127.0.0.1",8080))

ret = str(obj.recv(1024),encoding="utf-8")
print(ret)

View Code

 

socket更多功能

澳门新浦京娱乐游戏 6澳门新浦京娱乐游戏 7

    def bind(self, address): # real signature unknown; restored from __doc__
        """
        bind(address)

        Bind the socket to a local address.  For IP sockets, the address is a
        pair (host, port); the host must refer to the local host. For raw packet
        sockets the address is a tuple (ifname, proto [,pkttype [,hatype]])
        """
'''将套接字绑定到本地地址。是一个IP套接字的地址对(主机、端口),主机必须参考本地主机。'''
        pass

    def close(self): # real signature unknown; restored from __doc__
        """
        close()

        Close the socket.  It cannot be used after this call.
        """
        '''关闭socket'''
        pass

    def connect(self, address): # real signature unknown; restored from __doc__
        """
        connect(address)

        Connect the socket to a remote address.  For IP sockets, the address
        is a pair (host, port).
        """
        '''将套接字连接到远程地址。IP套接字的地址'''
        pass

    def connect_ex(self, address): # real signature unknown; restored from __doc__
        """
        connect_ex(address) -> errno

        This is like connect(address), but returns an error code (the errno value)
        instead of raising an exception when an error occurs.
        """
        pass

    def detach(self): # real signature unknown; restored from __doc__
        """
        detach()

        Close the socket object without closing the underlying file descriptor.
        The object cannot be used after this call, but the file descriptor
        can be reused for other purposes.  The file descriptor is returned.
        """
'''关闭套接字对象没有关闭底层的文件描述符。'''
        pass

    def fileno(self): # real signature unknown; restored from __doc__
        """
        fileno() -> integer

        Return the integer file descriptor of the socket.
        """
        '''返回整数的套接字的文件描述符。'''
        return 0

    def getpeername(self): # real signature unknown; restored from __doc__
        """
        getpeername() -> address info

        Return the address of the remote endpoint.  For IP sockets, the address
        info is a pair (hostaddr, port).
            """
        '''返回远程端点的地址。IP套接字的地址'''
        pass

    def getsockname(self): # real signature unknown; restored from __doc__
        """
        getsockname() -> address info

        Return the address of the local endpoint.  For IP sockets, the address
        info is a pair (hostaddr, port).
        """
        '''返回远程端点的地址。IP套接字的地址'''
        pass

    def getsockopt(self, level, option, buffersize=None): # real signature unknown; restored from __doc__
        """
        getsockopt(level, option[, buffersize]) -> value

        Get a socket option.  See the Unix manual for level and option.
        If a nonzero buffersize argument is given, the return value is a
        string of that length; otherwise it is an integer.
        """
        '''得到一个套接字选项'''
        pass

    def gettimeout(self): # real signature unknown; restored from __doc__
        """
        gettimeout() -> timeout

        Returns the timeout in seconds (float) associated with socket 
        operations. A timeout of None indicates that timeouts on socket 
        operations are disabled.
        """
        '''返回的超时秒数(浮动)与套接字相关联'''
        return timeout

    def ioctl(self, cmd, option): # real signature unknown; restored from __doc__
        """
        ioctl(cmd, option) -> long

        Control the socket with WSAIoctl syscall. Currently supported 'cmd' values are
        SIO_RCVALL:  'option' must be one of the socket.RCVALL_* constants.
        SIO_KEEPALIVE_VALS:  'option' is a tuple of (onoff, timeout, interval).
        """
        return 0

    def listen(self, backlog=None): # real signature unknown; restored from __doc__
        """
        listen([backlog])

        Enable a server to accept connections.  If backlog is specified, it must be
        at least 0 (if it is lower, it is set to 0); it specifies the number of
        unaccepted connections that the system will allow before refusing new
        connections. If not specified, a default reasonable value is chosen.
        """
        '''使服务器能够接受连接。'''
        pass

    def recv(self, buffersize, flags=None): # real signature unknown; restored from __doc__
        """
        recv(buffersize[, flags]) -> data

        Receive up to buffersize bytes from the socket.  For the optional flags
        argument, see the Unix manual.  When no data is available, block until
        at least one byte is available or until the remote end is closed.  When
        the remote end is closed and all data is read, return the empty string.
        """
'''当没有数据可用,阻塞,直到至少一个字节是可用的或远程结束之前关闭。'''
        pass

    def recvfrom(self, buffersize, flags=None): # real signature unknown; restored from __doc__
        """
        recvfrom(buffersize[, flags]) -> (data, address info)

        Like recv(buffersize, flags) but also return the sender's address info.
        """
        pass

    def recvfrom_into(self, buffer, nbytes=None, flags=None): # real signature unknown; restored from __doc__
        """
        recvfrom_into(buffer[, nbytes[, flags]]) -> (nbytes, address info)

        Like recv_into(buffer[, nbytes[, flags]]) but also return the sender's address info.
        """
        pass

    def recv_into(self, buffer, nbytes=None, flags=None): # real signature unknown; restored from __doc__
        """
        recv_into(buffer, [nbytes[, flags]]) -> nbytes_read

        A version of recv() that stores its data into a buffer rather than creating 
        a new string.  Receive up to buffersize bytes from the socket.  If buffersize 
        is not specified (or 0), receive up to the size available in the given buffer.

        See recv() for documentation about the flags.
        """
        pass

    def send(self, data, flags=None): # real signature unknown; restored from __doc__
        """
        send(data[, flags]) -> count

        Send a data string to the socket.  For the optional flags
        argument, see the Unix manual.  Return the number of bytes
        sent; this may be less than len(data) if the network is busy.
        """
        '''发送一个数据字符串到套接字。'''
        pass

    def sendall(self, data, flags=None): # real signature unknown; restored from __doc__
        """
        sendall(data[, flags])

        Send a data string to the socket.  For the optional flags
        argument, see the Unix manual.  This calls send() repeatedly
        until all data is sent.  If an error occurs, it's impossible
        to tell how much data has been sent.
        """
        '''发送一个数据字符串到套接字,直到所有数据发送完成'''
        pass

    def sendto(self, data, flags=None, *args, **kwargs): # real signature unknown; NOTE: unreliably restored from __doc__ 
        """
        sendto(data[, flags], address) -> count

        Like send(data, flags) but allows specifying the destination address.
        For IP sockets, the address is a pair (hostaddr, port).
        """
        pass

    def setblocking(self, flag): # real signature unknown; restored from __doc__
        """
        setblocking(flag)

        Set the socket to blocking (flag is true) or non-blocking (false).
        setblocking(True) is equivalent to settimeout(None);
        setblocking(False) is equivalent to settimeout(0.0).
        """
'''是否阻塞(默认True),如果设置False,那么accept和recv时一旦无数据,则报错。'''
        pass

    def setsockopt(self, level, option, value): # real signature unknown; restored from __doc__
        """
        setsockopt(level, option, value)

        Set a socket option.  See the Unix manual for level and option.
        The value argument can either be an integer or a string.
        """
        pass

    def settimeout(self, timeout): # real signature unknown; restored from __doc__
        """
        settimeout(timeout)

        Set a timeout on socket operations.  'timeout' can be a float,
        giving in seconds, or None.  Setting a timeout of None disables
        the timeout feature and is equivalent to setblocking(1).
        Setting a timeout of zero is the same as setblocking(0).
        """
        pass

    def share(self, process_id): # real signature unknown; restored from __doc__
        """
        share(process_id) -> bytes

        Share the socket with another process.  The target process id
        must be provided and the resulting bytes object passed to the target
        process.  There the shared socket can be instantiated by calling
        socket.fromshare().
        """
        return b""

    def shutdown(self, flag): # real signature unknown; restored from __doc__
        """
        shutdown(flag)

        Shut down the reading side of the socket (flag == SHUT_RD), the writing side
        of the socket (flag == SHUT_WR), or both ends (flag == SHUT_RDWR).
        """
        pass

    def _accept(self): # real signature unknown; restored from __doc__
        """
        _accept() -> (integer, address info)

        Wait for an incoming connection.  Return a new socket file descriptor
        representing the connection, and the address of the client.
        For IP sockets, the address info is a pair (hostaddr, port).
        """
        pass

更多功能

注:撸主知道大家懒,所以把全部功能的中文标记在每个功能的下面啦。下面撸主列一些经常用到的吧

sk.bind(address)

  s.bind(address)
将套接字绑定到地址。address地址的格式取决于地址族。在AF_INET下,以元组(host,port)的形式表示地址。

sk.listen(backlog)

  开始监听传入连接。backlog指定在拒绝连接之前,可以挂起的最大连接数量。

     
backlog等于5,表示内核已经接到了连接请求,但服务器还没有调用accept进行处理的连接个数最大为5
     
这个值不能无限大,因为要在内核中维护连接队列

sk.setblocking(bool)

  是否阻塞(默认True),如果设置False,那么accept和recv时一旦无数据,则报错。

sk.accept()

  接受连接并返回(conn,address),其中conn是新的套接字对象,可以用来接收和发送数据。address是连接客户端的地址。

  接收TCP
客户的连接(阻塞式)等待连接的到来

sk.connect(address)

  连接到address处的套接字。一般,address的格式为元组(hostname,port),如果连接出错,返回socket.error错误。

sk.connect_ex(address)

  同上,只不过会有返回值,连接成功时返回
0 ,连接失败时候返回编码,例如:10061

sk.close()

  关闭套接字

sk.recv(bufsize[,flag])

  接受套接字的数据。数据以字符串形式返回,bufsize指定最多可以接收的数量。flag提供有关消息的其他信息,通常可以忽略。

sk.recvfrom(bufsize[.flag])

  与recv()类似,但返回值是(data,address)。其中data是包含接收数据的字符串,address是发送数据的套接字地址。

sk.send(string[,flag])

  将string中的数据发送到连接的套接字。返回值是要发送的字节数量,该数量可能小于string的字节大小。即:可能未将指定内容全部发送。

sk.sendall(string[,flag])

  将string中的数据发送到连接的套接字,但在返回之前会尝试发送所有数据。成功返回None,失败则抛出异常。

     
内部通过递归调用send,将所有内容发送出去。

sk.sendto(string[,flag],address)

  将数据发送到套接字,address是形式为(ipaddr,port)的元组,指定远程地址。返回值是发送的字节数。该函数主要用于UDP协议。

sk.settimeout(timeout)

  设置套接字操作的超时期,timeout是一个浮点数,单位是秒。值为None表示没有超时期。一般,超时期应该在刚创建套接字时设置,因为它们可能用于连接的操作(如
client 连接最多等待5s )

sk.getpeername()

  返回连接套接字的远程地址。返回值通常是元组(ipaddr,port)。

sk.getsockname()

  返回套接字自己的地址。通常是一个元组(ipaddr,port)

sk.fileno()

  套接字的文件描述符

TCP:

 

澳门新浦京娱乐游戏 8澳门新浦京娱乐游戏 9

import  socketserver
服务端

class Myserver(socketserver.BaseRequestHandler):

    def handle(self):

        conn = self.request
        conn.sendall(bytes("你好,我是机器人",encoding="utf-8"))
        while True:
            ret_bytes = conn.recv(1024)
            ret_str = str(ret_bytes,encoding="utf-8")
            if ret_str == "q":
                break
            conn.sendall(bytes(ret_str+"你好我好大家好",encoding="utf-8"))

if __name__ == "__main__":
    server = socketserver.ThreadingTCPServer(("127.0.0.1",8080),Myserver)
    server.serve_forever()

客户端

import socket

obj = socket.socket()

obj.connect(("127.0.0.1",8080))

ret_bytes = obj.recv(1024)
ret_str = str(ret_bytes,encoding="utf-8")
print(ret_str)

while True:
    inp = input("你好请问您有什么问题? n >>>")
    if inp == "q":
        obj.sendall(bytes(inp,encoding="utf-8"))
        break
    else:
        obj.sendall(bytes(inp, encoding="utf-8"))
        ret_bytes = obj.recv(1024)
        ret_str = str(ret_bytes,encoding="utf-8")
        print(ret_str)

案例一 机器人聊天

澳门新浦京娱乐游戏 10澳门新浦京娱乐游戏 11

服务端

import socket

sk = socket.socket()

sk.bind(("127.0.0.1",8080))
sk.listen(5)

while True:
    conn,address = sk.accept()
    conn.sendall(bytes("欢迎光临我爱我家",encoding="utf-8"))

    size = conn.recv(1024)
    size_str = str(size,encoding="utf-8")
    file_size = int(size_str)

    conn.sendall(bytes("开始传送", encoding="utf-8"))

    has_size = 0
    f = open("db_new.jpg","wb")
    while True:
        if file_size == has_size:
            break
        date = conn.recv(1024)
        f.write(date)
        has_size += len(date)

    f.close()

客户端

import socket
import os

obj = socket.socket()

obj.connect(("127.0.0.1",8080))

ret_bytes = obj.recv(1024)
ret_str = str(ret_bytes,encoding="utf-8")
print(ret_str)

size = os.stat("yan.jpg").st_size
obj.sendall(bytes(str(size),encoding="utf-8"))

obj.recv(1024)

with open("yan.jpg","rb") as f:
    for line in f:
        obj.sendall(line)

案例二 上传文件

UdP

澳门新浦京娱乐游戏 12澳门新浦京娱乐游戏 13

import socket
ip_port = ('127.0.0.1',9999)
sk = socket.socket(socket.AF_INET,socket.SOCK_DGRAM,0)
sk.bind(ip_port)

while True:
    data = sk.recv(1024)
    print data




import socket
ip_port = ('127.0.0.1',9999)

sk = socket.socket(socket.AF_INET,socket.SOCK_DGRAM,0)
while True:
    inp = input('数据:').strip()
    if inp == 'exit':
        break
    sk.sendto(bytes(inp,encoding = "utf-8"),ip_port)

sk.close()

udp传输

WEB服务应用:

#!/usr/bin/env python
#coding:utf-8
import socket

def handle_request(client):
    buf = client.recv(1024)
    client.send("HTTP/1.1 200 OKrnrn")
    client.send("Hello, World")

def main():
    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    sock.bind(('localhost',8080))
    sock.listen(5)

    while True:
        connection, address = sock.accept()
        handle_request(connection)
        connection.close()

if __name__ == '__main__':
  main()

 

socket服务器的工作方式是这样的,不间断地运行以等待客户端的连接。一旦客户端连接上了,服务器就会将它添加到客户名单中,然后开始等待来自客户端的消息。

2.套接字对象内建方法

服务器端套接字函数

s.bind()   绑定地址(ip地址,端口)到套接字,参数必须是元组的格式例如:s.bind((‘127.0.0.1’,8009))

s.listen(5)  开始监听,5为最大挂起的连接数

s.accept()  被动接受客户端连接,阻塞,等待连接

客户端套接字函数

s.connect()  连接服务器端,参数必须是元组格式例如:s.connect((‘127,0.0.1’,8009))

公共用途的套接字函数

s.recv(1024)  接收TCP数据,1024为一次数据接收的大小

s.send(bytes)  发送TCP数据,python3发送数据的格式必须为bytes格式

s.sendall()  完整发送数据,内部循环调用send

s.close()  关闭套接字

IO多路复用 

I/O(input/output),即输入/输出端口。每个设备都会有一个专用的I/O地址,用来处理自己的输入输出信息首先什么是I/O:

I/O分为磁盘io和网络io,这里说的是网络io

IO多路复用:

I/O多路复用指:通过一种机制,可以监视多个描述符(socket),一旦某个描述符就绪(一般是读就绪或者写就绪),能够通知程序进行相应的读写操作。

Linux

Linux中的
select,poll,epoll 都是IO多路复用的机制。

Linux下网络I/O使用socket套接字来通信,普通I/O模型只能监听一个socket,而I/O多路复用可同时监听多个socket.

I/O多路复用避免阻塞在io上,原本为多进程或多线程来接收多个连接的消息变为单进程或单线程保存多个socket的状态后轮询处理.

Python  

Python中有一个select模块,其中提供了:select、poll、epoll三个方法,分别调用系统的
select,poll,epoll 从而实现IO多路复用。

Windows Python:

    提供: select

Mac Python:

    提供: select

Linux Python:

    提供: select、poll、epoll

对于select模块操作的方法:

句柄列表11, 句柄列表22, 句柄列表33 = select.select(句柄序列1, 句柄序列2, 句柄序列3, 超时时间)

参数: 可接受四个参数(前三个必须)
返回值:三个列表

select方法用来监视文件句柄,如果句柄发生变化,则获取该句柄。
1、当 参数1 序列中的句柄发生可读时(accetp和read),则获取发生变化的句柄并添加到 返回值1 序列中
2、当 参数2 序列中含有句柄时,则将该序列中所有的句柄添加到 返回值2 序列中
3、当 参数3 序列中的句柄发生错误时,则将该发生错误的句柄添加到 返回值3 序列中
4、当 超时时间 未设置,则select会一直阻塞,直到监听的句柄发生变化
5、当 超时时间 = 1时,那么如果监听的句柄均无任何变化,则select会阻塞 1 秒,之后返回三个空列表,如果监听的句柄有变化,则直接执行。

澳门新浦京娱乐游戏 14澳门新浦京娱乐游戏 15

import socket
import select


sk1 = socket.socket()
sk1.bind(("127.0.0.1",8001))
sk1.listen()

sk2 = socket.socket()
sk2.bind(("127.0.0.1",8002))
sk2.listen()

sk3 = socket.socket()
sk3.bind(("127.0.0.1",8003))
sk3.listen()

li = [sk1,sk2,sk3]

while True:
    r_list,w_list,e_list = select.select(li,[],[],1) # r_list可变化的
    for line in r_list: 
        conn,address = line.accept()
        conn.sendall(bytes("Hello World !",encoding="utf-8"))

利用select监听终端操作实例

澳门新浦京娱乐游戏 16澳门新浦京娱乐游戏 17

服务端:
sk1 = socket.socket()
sk1.bind(("127.0.0.1",8001))
sk1.listen()

inpu = [sk1,]

while True:
    r_list,w_list,e_list = select.select(inpu,[],[],1)
    for sk in r_list:
        if sk == sk1:
            conn,address = sk.accept()
            inpu.append(conn)
        else:
            try:
                ret = str(sk.recv(1024),encoding="utf-8")
                sk.sendall(bytes(ret+"hao",encoding="utf-8"))
            except Exception as ex:
                inpu.remove(sk)

客户端
import socket

obj = socket.socket()

obj.connect(('127.0.0.1',8001))

while True:
    inp = input("Please(q退出):n>>>")
    obj.sendall(bytes(inp,encoding="utf-8"))
    if inp == "q":
        break
    ret = str(obj.recv(1024),encoding="utf-8")
    print(ret)

利用select实现伪同时处理多个Socket客户端请求

澳门新浦京娱乐游戏 18澳门新浦京娱乐游戏 19

服务端:
import socket
sk1 = socket.socket()
sk1.bind(("127.0.0.1",8001))
sk1.listen()
inputs = [sk1]
import select
message_dic = {}
outputs = []
while True:

    r_list, w_list, e_list = select.select(inputs,[],inputs,1)
    print("正在监听的socket对象%d" % len(inputs))
    print(r_list)
    for sk1_or_conn in r_list:
        if sk1_or_conn == sk1:
            conn,address = sk1_or_conn.accept()
            inputs.append(conn)
            message_dic[conn] = []
        else:
            try:
                data_bytes = sk1_or_conn.recv(1024)
                data_str = str(data_bytes,encoding="utf-8")
                sk1_or_conn.sendall(bytes(data_str+"好",encoding="utf-8"))
            except Exception as ex:
                inputs.remove(sk1_or_conn)
            else:
                data_str = str(data_bytes,encoding="utf-8")
                message_dic[sk1_or_conn].append(data_str)
                outputs.append(sk1_or_conn)
        for conn in w_list:
            recv_str = message_dic[conn][0]
            del message_dic[conn][0]
            conn.sendall(bytes(recv_str+"好",encoding="utf-8"))
        for sk in e_list:
            inputs.remove(sk)

客户端:
import socket

obj = socket.socket()

obj.connect(('127.0.0.1',8001))

while True:
    inp = input("Please(q退出):n>>>")
    obj.sendall(bytes(inp,encoding="utf-8"))
    if inp == "q":
        break
    ret = str(obj.recv(1024),encoding="utf-8")
    print(ret)

利用select实现伪同时处理多个Socket客户端请求读写分离

 

澳门新浦京娱乐游戏 20

实例1.简单实现socket程序

server端

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
import socket
import time
IP_PORT = ('127.0.0.1',8009)
BUF_SIZE = 1024

tcp_server = socket.socket()
tcp_server.bind(IP_PORT)
tcp_server.listen(5)

while True:
    print("waiting for connection...")
    conn,addr = tcp_server.accept()
    print("...connected from:",addr)
    while True:
        data = tcp_server.recv(BUF_SIZE)
        if not data:break
        tcp_server.send('[%s] %s'%(time.ctime(),data))

tcp_server.close()

以上代码解释:

1~4行

第一行是Unix的启动信息行,随后导入time模块和socket模块

5~10行

IP_PORT为全局变量声明了IP地址和端口,表示bind()函数绑定在此地址上,把缓冲区的大小设定为1K,listen()函数表示最多允许多少个连接同时进来,后来的就会被拒绝掉

11~到最后一行

在进入服务器的循环后,被动等待连接的到来。当有连接时,进入对话循环,等待客户端发送数据。如果消息为空,表示客户端已经退出,就跳出循环等待下一个连接到来。得到客户端消息后,在消息前面加一个时间戳然后返回。最后一行不会执行,因为循环不会退出所以服务端也不会执行close()。只是提醒不要忘记调用close()函数。

client端  

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
import socket

HOST = '127.0.0.1'
PORT = 8009
BUF_SIZE = 1024
ADDR = (HOST,PORT)

client = socket.socket()
client.connect(ADDR)

while True:
    data = input(">>> ")
    if not data:break
    client.send(bytes(data,encoding='utf-8'))
    recv_data = client.recv(BUF_SIZE)
    if not recv_data:break
    print(recv_data.decode())

client.close()

5~11行

HOST和PORT变量表示服务器的IP地址与端口号。由于演示是在同一台服务器所以IP地址都是127.0.0.1,如果运行在其他服务器上要做相应的修改。端口号要与服务器端完全相同否则无法通信。缓冲区大小还是1K。

客户端套接字在10行创建然后就去连接服务器端

13~21行

客户端也无限循环,客户端的循环在以下两个条件的任意一个发生后就退出:1.用户输入为空的情况或者服务器端响应的消息为空。否则客户端会把用户输入的字符串发送给服务器进行处理,然后接收显示服务器返回来的带有时间戳的字符串。

运行客户端程序与服务端程序

以下是客户端的输入与输出

[[email protected] 博客示例]# python3 tclient.py 
>>> hello
[Thu Sep 15 22:29:12 2016] b'hello'
>>> nihao
[Thu Sep 15 22:29:32 2016] b'nihao'

以下是服务端输出

[[email protected] 博客示例]# python3 tserver.py 
waiting for connection...
...connected from: ('127.0.0.1', 55378)

socketserver

澳门新浦京娱乐游戏 21SocketServer内部使用
IO多路复用 以及 “多线程” 和 “多进程”
,从而实现并发处理多个客户端请求的Socket服务端。即:每个客户端请求连接到服务器时,Socket服务端都会在服务器是创建一个“线程”或者“进程”
专门负责处理当前客户端的所有请求。

ThreadingTCPServer

ThreadingTCPServer实现的Soket服务器内部会为每个client创建一个
线程”,该线程用来和客户端进行交互。

1、ThreadingTCPServer基础

使用ThreadingTCPServer:

  • 创建一个继承自
    SocketServer.BaseRequestHandler 的类
  • 类中必须定义一个名称为
    handle 的方法
  • 启动ThreadingTCPServer

澳门新浦京娱乐游戏 22澳门新浦京娱乐游戏 23

import  socketserver

class Myserver(socketserver.BaseRequestHandler):

    def handle(self):

        conn = self.request
        conn.sendall(bytes("你好,我是机器人",encoding="utf-8"))
        while True:
            ret_bytes = conn.recv(1024)
            ret_str = str(ret_bytes,encoding="utf-8")
            if ret_str == "q":
                break
            conn.sendall(bytes(ret_str+"你好我好大家好",encoding="utf-8"))

if __name__ == "__main__":
    server = socketserver.ThreadingTCPServer(("127.0.0.1",8080),Myserver)
    server.serve_forever()

服务端

澳门新浦京娱乐游戏 24澳门新浦京娱乐游戏 25

import socket

obj = socket.socket()

obj.connect(("127.0.0.1",8080))

ret_bytes = obj.recv(1024)
ret_str = str(ret_bytes,encoding="utf-8")
print(ret_str)

while True:
    inp = input("你好请问您有什么问题? n >>>")
    if inp == "q":
        obj.sendall(bytes(inp,encoding="utf-8"))
        break
    else:
        obj.sendall(bytes(inp, encoding="utf-8"))
        ret_bytes = obj.recv(1024)
        ret_str = str(ret_bytes,encoding="utf-8")
        print(ret_str)

客户端

2、ThreadingTCPServer源码剖析

ThreadingTCPServer的类图关系如下:

澳门新浦京娱乐游戏 26

内部调用流程为:

  • 启动服务端程序
  • 执行
    TCPServer.__init__ 方法,创建服务端Socket对象并绑定 IP 和
    端口
  • 执行
    BaseServer.__init__
    方法,将自定义的继承自SocketServer.BaseRequestHandler 的类
    MyRequestHandle赋值给 self.RequestHandlerClass
  • 执行
    BaseServer.server_forever 方法,While
    循环一直监听是否有客户端请求到达 …
  • 当客户端连接到达服务器
  • 执行
    ThreadingMixIn.process_request 方法,创建一个 “线程”
    用来处理请求
  • 执行 ThreadingMixIn.process_request_thread
    方法
  • 执行
    BaseServer.finish_request 方法,执行 self.RequestHandlerClass()
     即:执行 自定义 MyRequestHandler
    的构造方法(自动调用基类BaseRequestHandler的构造方法,在该构造方法中又会调用
    MyRequestHandler的handle方法)

 

相对应的源码如下:

澳门新浦京娱乐游戏 27澳门新浦京娱乐游戏 28

class BaseServer:

    """Base class for server classes.

    Methods for the caller:

    - __init__(server_address, RequestHandlerClass)
    - serve_forever(poll_interval=0.5)
    - shutdown()
    - handle_request()  # if you do not use serve_forever()
    - fileno() -> int   # for select()

    Methods that may be overridden:

    - server_bind()
    - server_activate()
    - get_request() -> request, client_address
    - handle_timeout()
    - verify_request(request, client_address)
    - server_close()
    - process_request(request, client_address)
    - shutdown_request(request)
    - close_request(request)
    - handle_error()

    Methods for derived classes:

    - finish_request(request, client_address)

    Class variables that may be overridden by derived classes or
    instances:

    - timeout
    - address_family
    - socket_type
    - allow_reuse_address

    Instance variables:

    - RequestHandlerClass
    - socket

    """

    timeout = None

    def __init__(self, server_address, RequestHandlerClass):
        """Constructor.  May be extended, do not override."""
        self.server_address = server_address
        self.RequestHandlerClass = RequestHandlerClass
        self.__is_shut_down = threading.Event()
        self.__shutdown_request = False

    def server_activate(self):
        """Called by constructor to activate the server.

        May be overridden.

        """
        pass

    def serve_forever(self, poll_interval=0.5):
        """Handle one request at a time until shutdown.

        Polls for shutdown every poll_interval seconds. Ignores
        self.timeout. If you need to do periodic tasks, do them in
        another thread.
        """
        self.__is_shut_down.clear()
        try:
            while not self.__shutdown_request:
                # XXX: Consider using another file descriptor or
                # connecting to the socket to wake this up instead of
                # polling. Polling reduces our responsiveness to a
                # shutdown request and wastes cpu at all other times.
                r, w, e = _eintr_retry(select.select, [self], [], [],
                                       poll_interval)
                if self in r:
                    self._handle_request_noblock()
        finally:
            self.__shutdown_request = False
            self.__is_shut_down.set()

    def shutdown(self):
        """Stops the serve_forever loop.

        Blocks until the loop has finished. This must be called while
        serve_forever() is running in another thread, or it will
        deadlock.
        """
        self.__shutdown_request = True
        self.__is_shut_down.wait()

    # The distinction between handling, getting, processing and
    # finishing a request is fairly arbitrary.  Remember:
    #
    # - handle_request() is the top-level call.  It calls
    #   select, get_request(), verify_request() and process_request()
    # - get_request() is different for stream or datagram sockets
    # - process_request() is the place that may fork a new process
    #   or create a new thread to finish the request
    # - finish_request() instantiates the request handler class;
    #   this constructor will handle the request all by itself

    def handle_request(self):
        """Handle one request, possibly blocking.

        Respects self.timeout.
        """
        # Support people who used socket.settimeout() to escape
        # handle_request before self.timeout was available.
        timeout = self.socket.gettimeout()
        if timeout is None:
            timeout = self.timeout
        elif self.timeout is not None:
            timeout = min(timeout, self.timeout)
        fd_sets = _eintr_retry(select.select, [self], [], [], timeout)
        if not fd_sets[0]:
            self.handle_timeout()
            return
        self._handle_request_noblock()

    def _handle_request_noblock(self):
        """Handle one request, without blocking.

        I assume that select.select has returned that the socket is
        readable before this function was called, so there should be
        no risk of blocking in get_request().
        """
        try:
            request, client_address = self.get_request()
        except socket.error:
            return
        if self.verify_request(request, client_address):
            try:
                self.process_request(request, client_address)
            except:
                self.handle_error(request, client_address)
                self.shutdown_request(request)

    def handle_timeout(self):
        """Called if no new request arrives within self.timeout.

        Overridden by ForkingMixIn.
        """
        pass

    def verify_request(self, request, client_address):
        """Verify the request.  May be overridden.

        Return True if we should proceed with this request.

        """
        return True

    def process_request(self, request, client_address):
        """Call finish_request.

        Overridden by ForkingMixIn and ThreadingMixIn.

        """
        self.finish_request(request, client_address)
        self.shutdown_request(request)

    def server_close(self):
        """Called to clean-up the server.

        May be overridden.

        """
        pass

    def finish_request(self, request, client_address):
        """Finish one request by instantiating RequestHandlerClass."""
        self.RequestHandlerClass(request, client_address, self)

    def shutdown_request(self, request):
        """Called to shutdown and close an individual request."""
        self.close_request(request)

    def close_request(self, request):
        """Called to clean up an individual request."""
        pass

    def handle_error(self, request, client_address):
        """Handle an error gracefully.  May be overridden.

        The default is to print a traceback and continue.

        """
        print '-'*40
        print 'Exception happened during processing of request from',
        print client_address
        import traceback
        traceback.print_exc() # XXX But this goes to stderr!
        print '-'*40

Baseserver

澳门新浦京娱乐游戏 29澳门新浦京娱乐游戏 30

class TCPServer(BaseServer):

    """Base class for various socket-based server classes.

    Defaults to synchronous IP stream (i.e., TCP).

    Methods for the caller:

    - __init__(server_address, RequestHandlerClass, bind_and_activate=True)
    - serve_forever(poll_interval=0.5)
    - shutdown()
    - handle_request()  # if you don't use serve_forever()
    - fileno() -> int   # for select()

    Methods that may be overridden:

    - server_bind()
    - server_activate()
    - get_request() -> request, client_address
    - handle_timeout()
    - verify_request(request, client_address)
    - process_request(request, client_address)
    - shutdown_request(request)
    - close_request(request)
    - handle_error()

    Methods for derived classes:

    - finish_request(request, client_address)

    Class variables that may be overridden by derived classes or
    instances:

    - timeout
    - address_family
    - socket_type
    - request_queue_size (only for stream sockets)
    - allow_reuse_address

    Instance variables:

    - server_address
    - RequestHandlerClass
    - socket

    """

    address_family = socket.AF_INET

    socket_type = socket.SOCK_STREAM

    request_queue_size = 5

    allow_reuse_address = False

    def __init__(self, server_address, RequestHandlerClass, bind_and_activate=True):
        """Constructor.  May be extended, do not override."""
        BaseServer.__init__(self, server_address, RequestHandlerClass)
        self.socket = socket.socket(self.address_family,
                                    self.socket_type)
        if bind_and_activate:
            try:
                self.server_bind()
                self.server_activate()
            except:
                self.server_close()
                raise

    def server_bind(self):
        """Called by constructor to bind the socket.

        May be overridden.

        """
        if self.allow_reuse_address:
            self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
        self.socket.bind(self.server_address)
        self.server_address = self.socket.getsockname()

    def server_activate(self):
        """Called by constructor to activate the server.

        May be overridden.

        """
        self.socket.listen(self.request_queue_size)

    def server_close(self):
        """Called to clean-up the server.

        May be overridden.

        """
        self.socket.close()

    def fileno(self):
        """Return socket file number.

        Interface required by select().

        """
        return self.socket.fileno()

    def get_request(self):
        """Get the request and client address from the socket.

        May be overridden.

        """
        return self.socket.accept()

    def shutdown_request(self, request):
        """Called to shutdown and close an individual request."""
        try:
            #explicitly shutdown.  socket.close() merely releases
            #the socket and waits for GC to perform the actual close.
            request.shutdown(socket.SHUT_WR)
        except socket.error:
            pass #some platforms may raise ENOTCONN here
        self.close_request(request)

    def close_request(self, request):
        """Called to clean up an individual request."""
        request.close()

TCP server

澳门新浦京娱乐游戏 31澳门新浦京娱乐游戏 32

class ThreadingMixIn:
    """Mix-in class to handle each request in a new thread."""

    # Decides how threads will act upon termination of the
    # main process
    daemon_threads = False

    def process_request_thread(self, request, client_address):
        """Same as in BaseServer but as a thread.

        In addition, exception handling is done here.

        """
        try:
            self.finish_request(request, client_address)
            self.shutdown_request(request)
        except:
            self.handle_error(request, client_address)
            self.shutdown_request(request)

    def process_request(self, request, client_address):
        """Start a new thread to process the request."""
        t = threading.Thread(target = self.process_request_thread,
                             args = (request, client_address))
        t.daemon = self.daemon_threads
        t.start()

ThreadingMixIn

澳门新浦京娱乐游戏 33澳门新浦京娱乐游戏 34

class BaseRequestHandler:

    """Base class for request handler classes.

    This class is instantiated for each request to be handled.  The
    constructor sets the instance variables request, client_address
    and server, and then calls the handle() method.  To implement a
    specific service, all you need to do is to derive a class which
    defines a handle() method.

    The handle() method can find the request as self.request, the
    client address as self.client_address, and the server (in case it
    needs access to per-server information) as self.server.  Since a
    separate instance is created for each request, the handle() method
    can define arbitrary other instance variariables.

    """

    def __init__(self, request, client_address, server):
        self.request = request
        self.client_address = client_address
        self.server = server
        self.setup()
        try:
            self.handle()
        finally:
            self.finish()

    def setup(self):
        pass

    def handle(self):
        pass

    def finish(self):
        pass

SocketServer.BaseRequestHandler

SocketServer的ThreadingTCPServer之所以可以同时处理请求得益于 select 和 Threading 两个东西,其实本质上就是在服务器端为每一个客户端创建一个线程,当前线程用来处理对应客户端的请求,所以,可以支持同时n个客户端链接(长连接)。

 

不要走开,下面是完整的源代码:

 3.socketserver模块

socketserver是标准库中的一个高级别的模块。用于简化实现网络客户端与服务器所需要的大量样板代码。模块中已经实现了一些可以使用的类。

实例1:使用socketserver实现与上面socket()实例一样的功能

服务端程序代码

#!/usr/bin/env python
# _*_ coding:utf-8 _*_
import socketserver
import time

HOST = '127.0.0.1'
PORT = 8009
ADDR = (HOST,PORT)
BUF_SIZE = 1024

class Myserver(socketserver.BaseRequestHandler):
    def handle(self):
        while True:
            print("...connected from:",self.client_address)
            data = self.request.recv(BUF_SIZE)
            if not data:break
            self.request.send(bytes("%s %s"%(time.ctime(),data)))

server = socketserver.ThreadingTCPServer(ADDR,Myserver)
print("waiting for connection...")
server.serve_forever()

11~17行

主要的工作在这里。从socketserver的BaseRequestHandler类中派生出一个子类,并重写handle()函数。

在有客户端发进来的消息的时候,handle()函数就会被调用。

19~21行

代码的最后一部分用给定的IP地址和端口加上自定义处理请求的类(Myserver)。然后进入等待客户端请求与处理客户端请求的无限循环中。

客户端程序代码

import socket
HOST = '127.0.0.1'
PORT = 8009
ADDR = (HOST,PORT)
BUF_SIZE = 1024

client = socket.socket()
client.connect(ADDR)

while True:
    data = input(">>> ")
    if not data:continue
    client.send(bytes(data,encoding='utf-8'))
    recv_data = client.recv(BUF_SIZE)
    if not recv_data:break
    print(recv_data.decode())

client.close()

执行服务端和客户端代码  

下面是客户端输出

[[email protected] blog示例2]# python3 tsocketclient.py 
>>> hello
Thu Sep 15 23:53:31 2016 b'hello'
>>> nihao
Thu Sep 15 23:53:49 2016 b'nihao'
>>> hehe
Thu Sep 15 23:53:53 2016 b'hehe'

下面是服务端输出

[[email protected] blog示例2]# python3 tsocketserver.py 
waiting for connection...
...connected from: ('127.0.0.1', 55385)
...connected from: ('127.0.0.1', 55385)
...connected from: ('127.0.0.1', 55385)
...connected from: ('127.0.0.1', 55385)

 

1.socket模块 要使用socket.socket()函数来创建套接字。其语法如下:
socket.socket(socket_family,socket_type,…

// Set time limit to indefinite execution
set_time_limit (0);

// Set the ip and port we will listen on
$address = 'localhost';
$port = 10000;
$max_clients = 10;

// Array that will hold client information
$client = Array();

// Create a TCP Stream socket
$sock = socket_create(AF_INET, SOCK_STREAM, 0);
// Bind the socket to an address/port
socket_bind($sock, $address, $port) or die('Could not bind to address');
// Start listening for connections
socket_listen($sock);

echo "Waiting for connections...rn";

// Loop continuously
while (true) {
    // Setup clients listen socket for reading
    $read[0] = $sock;
    for ($i = 0; $i < $max_clients; $i++) {
        if (isset($client[$i]['sock']))
            $read[$i + 1] = $client[$i]['sock'];
    }
    // Set up a blocking call to socket_select()
    if (socket_select($read, $write = NULL, $except = NULL, $tv_sec = 5) < 1)
        continue;
    /* if a new connection is being made add it to the client array */
    if (in_array($sock, $read)) {
        for ($i = 0; $i < $max_clients; $i++) {
            if (empty($client[$i]['sock'])) {
                $client[$i]['sock'] = socket_accept($sock);
                echo "New client connected $irn";
                break;
            }
            elseif ($i == $max_clients - 1)
                echo "Too many clients...rn";
        }
    } // end if in_array

    // If a client is trying to write - handle it now
    for ($i = 0; $i < $max_clients; $i++) { // for each client
        if (isset($client[$i]['sock'])) {
            if (in_array($client[$i]['sock'], $read)) {
                $input = socket_read($client[$i]['sock'], 1024);
                if ($input == null) {
                    echo "Client disconnecting $irn";
                    // Zero length string meaning disconnected
                    unset($client[$i]);
                } else {
                    echo "New input received $irn";
                    // send it to the other clients
                    for ($j = 0; $j < $max_clients; $j++) {
                        if (isset($client[$j]['sock']) && $j != $i) {
                            echo "Writing '$input' to client $jrn";
                            socket_write($client[$j]['sock'], $input, strlen($input));
                        }
                    }
                    if ($input == 'exit') {
                        // requested disconnect
                        socket_close($client[$i]['sock']);
                    }
                }
            } else {
                echo "Client disconnected $irn";
                // Close the socket
                socket_close($client[$i]['sock']);
                unset($client[$i]);
            }
        }
    }
} // end while
// Close the master sockets
socket_close($sock);

啊呀,乍一看这似乎是一个大工程,但是我们可以先将它分解为几个较小的部分。第一部分是创建服务器。Lines:2至20。

这部分代码设置了变量、地址、端口、最大客户端和客户端数组。接下来创建socket并将其绑定到我们指定的地址和端口上。

下面我们要做的事情就是执行一个死循环(实际上我们是故意的!)。Lines:22至32。在这部分代码中我们做的第一步是设置 $read 数组。此数组包含所有客户端的套接字和我们主服务器的套接字。这个变量稍后会用于select语句:告诉PHP监听来自这些客户端的每一条消息。

socket_select()的最后一个参数告诉我们的服务器在返回值之前最多等待5秒钟。如果它的返回值小于1,那么就表示没有收到任何数据,所以只需要返回循环顶部,继续等待。

脚本的下一个部分,是增加新的客户端到数组中。Lines:33至44。

将新的客户端放置在列表的末尾。检查以确保客户端的数量没有超过我们想要服务器处理的数量。

下面要介绍的代码块相当大,也是服务器的主要部分。当客户端将消息发送到服务器时,就需要这块代码挺身而出来处理。消息可以是各种各样的,断开消息、实际断开——只要是服务器需要处理的消息。Lines:46至末尾。

代码循环通过每个客户端并检查是否收到来自于它们的消息。如果是,获取输入的内容。根据输入来检查这是否是一个断开消息,如果是那就从数组中删除它们,反之,那它就是一个正常的消息,那我们的服务器再次通过所有客户端,并一个一个写信息给他们,跳过发送者。

好了,下面试试创造你自己的聊天服务器吧!

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