Python socket编程

Posted 2020-09-05

Python  socket编程 （转）

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 http://www.cnblogs.com/ 时，你会打开一个套接字，然后连接到 http://www.cnblogs.com/ 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 http://docs.python.org/library/socket.html

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】

先来创建一个socket服务端吧

 1 #coding:utf8
 2 
 3 import socket
 4 
 5 sk = socket.socket()
 6 sk.bind(("127.0.0.1",8080))
 7 sk.listen(5)
 8 
 9 conn,address = sk.accept()
10 sk.sendall(bytes("Hello world",encoding="utf-8"))

server

1 import socket
2 
3 obj = socket.socket()
4 obj.connect(("127.0.0.1",8080))
5 
6 ret = str(obj.recv(1024),encoding="utf-8")
7 print(ret)

View Code

 

socket更多功能

  1 def bind(self, address): # real signature unknown; restored from __doc__
  2         """
  3         bind(address)
  4         
  5         Bind the socket to a local address.  For IP sockets, the address is a
  6         pair (host, port); the host must refer to the local host. For raw packet
  7         sockets the address is a tuple (ifname, proto [,pkttype [,hatype]])
  8         """
  9 ‘‘‘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。‘‘‘
 10         pass
 11 
 12     def close(self): # real signature unknown; restored from __doc__
 13         """
 14         close()
 15         
 16         Close the socket.  It cannot be used after this call.
 17         """
 18         ‘‘‘关闭socket‘‘‘
 19         pass
 20 
 21     def connect(self, address): # real signature unknown; restored from __doc__
 22         """
 23         connect(address)
 24         
 25         Connect the socket to a remote address.  For IP sockets, the address
 26         is a pair (host, port).
 27         """
 28         ‘‘‘将套接字连接到远程地址。IP套接字的地址‘‘‘
 29         pass
 30 
 31     def connect_ex(self, address): # real signature unknown; restored from __doc__
 32         """
 33         connect_ex(address) -> errno
 34         
 35         This is like connect(address), but returns an error code (the errno value)
 36         instead of raising an exception when an error occurs.
 37         """
 38         pass
 39 
 40     def detach(self): # real signature unknown; restored from __doc__
 41         """
 42         detach()
 43         
 44         Close the socket object without closing the underlying file descriptor.
 45         The object cannot be used after this call, but the file descriptor
 46         can be reused for other purposes.  The file descriptor is returned.
 47         """
 48 ‘‘‘关闭套接字对象没有关闭底层的文件描述符。‘‘‘
 49         pass
 50 
 51     def fileno(self): # real signature unknown; restored from __doc__
 52         """
 53         fileno() -> integer
 54         
 55         Return the integer file descriptor of the socket.
 56         """
 57         ‘‘‘返回整数的套接字的文件描述符。‘‘‘
 58         return 0
 59 
 60     def getpeername(self): # real signature unknown; restored from __doc__
 61         """
 62         getpeername() -> address info
 63         
 64         Return the address of the remote endpoint.  For IP sockets, the address
 65         info is a pair (hostaddr, port).
 66             """
 67         ‘‘‘返回远程端点的地址。IP套接字的地址‘‘‘
 68         pass
 69 
 70     def getsockname(self): # real signature unknown; restored from __doc__
 71         """
 72         getsockname() -> address info
 73         
 74         Return the address of the local endpoint.  For IP sockets, the address
 75         info is a pair (hostaddr, port).
 76         """
 77         ‘‘‘返回远程端点的地址。IP套接字的地址‘‘‘
 78         pass
 79 
 80     def getsockopt(self, level, option, buffersize=None): # real signature unknown; restored from __doc__
 81         """
 82         getsockopt(level, option[, buffersize]) -> value
 83         
 84         Get a socket option.  See the Unix manual for level and option.
 85         If a nonzero buffersize argument is given, the return value is a
 86         string of that length; otherwise it is an integer.
 87         """
 88         ‘‘‘得到一个套接字选项‘‘‘
 89         pass
 90 
 91     def gettimeout(self): # real signature unknown; restored from __doc__
 92         """
 93         gettimeout() -> timeout
 94         
 95         Returns the timeout in seconds (float) associated with socket 
 96         operations. A timeout of None indicates that timeouts on socket 
 97         operations are disabled.
 98         """
 99         ‘‘‘返回的超时秒数(浮动)与套接字相关联‘‘‘
100         return timeout
101 
102     def ioctl(self, cmd, option): # real signature unknown; restored from __doc__
103         """
104         ioctl(cmd, option) -> long
105         
106         Control the socket with WSAIoctl syscall. Currently supported ‘cmd‘ values are
107         SIO_RCVALL:  ‘option‘ must be one of the socket.RCVALL_* constants.
108         SIO_KEEPALIVE_VALS:  ‘option‘ is a tuple of (onoff, timeout, interval).
109         """
110         return 0
111 
112     def listen(self, backlog=None): # real signature unknown; restored from __doc__
113         """
114         listen([backlog])
115         
116         Enable a server to accept connections.  If backlog is specified, it must be
117         at least 0 (if it is lower, it is set to 0); it specifies the number of
118         unaccepted connections that the system will allow before refusing new
119         connections. If not specified, a default reasonable value is chosen.
120         """
121         ‘‘‘使服务器能够接受连接。‘‘‘
122         pass
123 
124     def recv(self, buffersize, flags=None): # real signature unknown; restored from __doc__
125         """
126         recv(buffersize[, flags]) -> data
127         
128         Receive up to buffersize bytes from the socket.  For the optional flags
129         argument, see the Unix manual.  When no data is available, block until
130         at least one byte is available or until the remote end is closed.  When
131         the remote end is closed and all data is read, return the empty string.
132         """
133 ‘‘‘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。‘‘‘
134         pass
135 
136     def recvfrom(self, buffersize, flags=None): # real signature unknown; restored from __doc__
137         """
138         recvfrom(buffersize[, flags]) -> (data, address info)
139         
140         Like recv(buffersize, flags) but also return the sender‘s address info.
141         """
142         pass
143 
144     def recvfrom_into(self, buffer, nbytes=None, flags=None): # real signature unknown; restored from __doc__
145         """
146         recvfrom_into(buffer[, nbytes[, flags]]) -> (nbytes, address info)
147         
148         Like recv_into(buffer[, nbytes[, flags]]) but also return the sender‘s address info.
149         """
150         pass
151 
152     def recv_into(self, buffer, nbytes=None, flags=None): # real signature unknown; restored from __doc__
153         """
154         recv_into(buffer, [nbytes[, flags]]) -> nbytes_read
155         
156         A version of recv() that stores its data into a buffer rather than creating 
157         a new string.  Receive up to buffersize bytes from the socket.  If buffersize 
158         is not specified (or 0), receive up to the size available in the given buffer.
159         
160         See recv() for documentation about the flags.
161         """
162         pass
163 
164     def send(self, data, flags=None): # real signature unknown; restored from __doc__
165         """
166         send(data[, flags]) -> count
167         
168         Send a data string to the socket.  For the optional flags
169         argument, see the Unix manual.  Return the number of bytes
170         sent; this may be less than len(data) if the network is busy.
171         """
172         ‘‘‘发送一个数据字符串到套接字。‘‘‘
173         pass
174 
175     def sendall(self, data, flags=None): # real signature unknown; restored from __doc__
176         """
177         sendall(data[, flags])
178         
179         Send a data string to the socket.  For the optional flags
180         argument, see the Unix manual.  This calls send() repeatedly
181         until all data is sent.  If an error occurs, it‘s impossible
182         to tell how much data has been sent.
183         """
184         ‘‘‘发送一个数据字符串到套接字，直到所有数据发送完成‘‘‘
185         pass
186 
187     def sendto(self, data, flags=None, *args, **kwargs): # real signature unknown; NOTE: unreliably restored from __doc__ 
188         """
189         sendto(data[, flags], address) -> count
190         
191         Like send(data, flags) but allows specifying the destination address.
192         For IP sockets, the address is a pair (hostaddr, port).
193         """
194         pass
195 
196     def setblocking(self, flag): # real signature unknown; restored from __doc__
197         """
198         setblocking(flag)
199         
200         Set the socket to blocking (flag is true) or non-blocking (false).
201         setblocking(True) is equivalent to settimeout(None);
202         setblocking(False) is equivalent to settimeout(0.0).
203         """
204 ‘‘‘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。‘‘‘
205         pass
206 
207     def setsockopt(self, level, option, value): # real signature unknown; restored from __doc__
208         """
209         setsockopt(level, option, value)
210         
211         Set a socket option.  See the Unix manual for level and option.
212         The value argument can either be an integer or a string.
213         """
214         pass
215 
216     def settimeout(self, timeout): # real signature unknown; restored from __doc__
217         """
218         settimeout(timeout)
219         
220         Set a timeout on socket operations.  ‘timeout‘ can be a float,
221         giving in seconds, or None.  Setting a timeout of None disables
222         the timeout feature and is equivalent to setblocking(1).
223         Setting a timeout of zero is the same as setblocking(0).
224         """
225         pass
226 
227     def share(self, process_id): # real signature unknown; restored from __doc__
228         """
229         share(process_id) -> bytes
230         
231         Share the socket with another process.  The target process id
232         must be provided and the resulting bytes object passed to the target
233         process.  There the shared socket can be instantiated by calling
234         socket.fromshare().
235         """
236         return b""
237 
238     def shutdown(self, flag): # real signature unknown; restored from __doc__
239         """
240         shutdown(flag)
241         
242         Shut down the reading side of the socket (flag == SHUT_RD), the writing side
243         of the socket (flag == SHUT_WR), or both ends (flag == SHUT_RDWR).
244         """
245         pass
246 
247     def _accept(self): # real signature unknown; restored from __doc__
248         """
249         _accept() -> (integer, address info)
250         
251         Wait for an incoming connection.  Return a new socket file descriptor
252         representing the connection, and the address of the client.
253         For IP sockets, the address info is a pair (hostaddr, port).
254         """
255         pass
256     

View Code

 

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：

 1 import  socketserver
 2 服务端
 3 
 4 class Myserver(socketserver.BaseRequestHandler):
 5 
 6     def handle(self):
 7 
 8         conn = self.request
 9         conn.sendall(bytes("你好，我是机器人",encoding="utf-8"))
10         while True:
11             ret_bytes = conn.recv(1024)
12             ret_str = str(ret_bytes,encoding="utf-8")
13             if ret_str == "q":
14                 break
15             conn.sendall(bytes(ret_str+"你好我好大家好",encoding="utf-8"))
16 
17 if __name__ == "__main__":
18     server = socketserver.ThreadingTCPServer(("127.0.0.1",8080),Myserver)
19     server.serve_forever()
20 
21 客户端
22 
23 import socket
24 
25 obj = socket.socket()
26 
27 obj.connect(("127.0.0.1",8080))
28 
29 ret_bytes = obj.recv(1024)
30 ret_str = str(ret_bytes,encoding="utf-8")
31 print(ret_str)
32 
33 while True:
34     inp = input("你好请问您有什么问题？ \\n >>>")
35     if inp == "q":
36         obj.sendall(bytes(inp,encoding="utf-8"))
37         break
38     else:
39         obj.sendall(bytes(inp, encoding="utf-8"))
40         ret_bytes = obj.recv(1024)
41         ret_str = str(ret_bytes,encoding="utf-8")
42         print(ret_str)

机器人聊天

 1 服务端
 2 
 3 import socket
 4 
 5 sk = socket.socket()
 6 
 7 sk.bind(("127.0.0.1",8080))
 8 sk.listen(5)
 9 
10 while True:
11     conn,address = sk.accept()
12     conn.sendall(bytes("欢迎光临我爱我家",encoding="utf-8"))
13 
14     size = conn.recv(1024)
15     size_str = str(size,encoding="utf-8")
16     file_size = int(size_str)
17 
18     conn.sendall(bytes("开始传送", encoding="utf-8"))
19 
20     has_size = 0
21     f = open("db_new.jpg","wb")
22     while True:
23         if file_size == has_size:
24             break
25         date = conn.recv(1024)
26         f.write(date)
27         has_size += len(date)
28 
29     f.close()
30 
31 客户端
32 
33 import socket
34 import os
35 
36 obj = socket.socket()
37 
38 obj.connect(("127.0.0.1",8080))
39 
40 ret_bytes = obj.recv(1024)
41 ret_str = str(ret_bytes,encoding="utf-8")
42 print(ret_str)
43 
44 size = os.stat("yan.jpg").st_size
45 obj.sendall(bytes(str(size),encoding="utf-8"))
46 
47 obj.recv(1024)
48 
49 with open("yan.jpg","rb") as f:
50     for line in f:
51         obj.sendall(line)

上传文件

 

UDP：

 1 import socket
 2 ip_port = (‘127.0.0.1‘,9999)
 3 sk = socket.socket(socket.AF_INET,socket.SOCK_DGRAM,0)
 4 sk.bind(ip_port)
 5 
 6 while True:
 7     data = sk.recv(1024)
 8     print data
 9 
10 
11 
12 
13 import socket
14 ip_port = (‘127.0.0.1‘,9999)
15 
16 sk = socket.socket(socket.AF_INET,socket.SOCK_DGRAM,0)
17 while True:
18     inp = input(‘数据：‘).strip()
19     if inp == ‘exit‘:
20         break
21     sk.sendto(bytes(inp,encoding = "utf-8"),ip_port)
22 
23 sk.close()
24 
25 udp传输

UDP传输

 

WEB服务应用：

 1 #coding:utf-8
 2 import socket
 3   
 4 def handle_request(client):
 5     buf = client.recv(1024)
 6     client.send("HTTP/1.1 200 OK\\r\\n\\r\\n")
 7     client.send("Hello, World")
 8   
 9 def main():
10     sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
11     sock.bind((‘localhost‘,8080))
12     sock.listen(5)
13   
14     while True:
15         connection, address = sock.accept()
16         handle_request(connection)
17         connection.close()
18   
19 if __name__ == ‘__main__‘:
20   main()

UDP传输